the e.o. paton electric welding institute of the … · technologies equipment technical...

TECHNOLOGIES EQUIPMENT TECHNICAL DIAGNOSTICS

COMPUTER PROGRAMS MATERIALS

The Institute has been founded on the facility of laboratory of welding belonged to the Chair of Engineering Constructions of the All-Ukrainian Academy of Sciences (A-UkrAS) and Electric Welding Committee in accor-dance with the resolution of the Presidium of the A-UkrAS by the initiative of academician Paton Evgeny Os-carovich, the outstanding engineer and scientist, in January, 1934. E.O.Paton became the fi rst director of the Electric Welding Institute and defi ned the main directions of its scientifi c activity. Since 1953 and until now the ac-ademician Paton Boris Evgenievich is the director of the Institute.

At the fi rst stage the possibility of manufacture of welded structures, being not inferior by their strength and reli-ability to riveted ones, was proved in principle. This expired to mass implementation of new technologies of weld-ing into industry. By 1940 the development of a high-effi cient process of automatic submerged arc welding was fi nalized and its implementation at the plants of the country started. It was this process that was implemented by the Institute staff in shops of tank plant in the Urals during the Great Patriotic War for joining of an armored steel, thus allowing creation of production line for manufacture of welded hulls of tanks T-34 and mechanization of welding of other military machinery. Pre-war and war stages in the Institute activity are the periods of establish-ment of the new scientifi c school, which convincing confi rmation of authority was awarding the name of Paton Evgeny Oscarovich to the Institute of Electric Welding in 1945.

Over the years of reconstruction of national economy, ruined by the war, the efforts of the Institute staff were di-rected to the widening of fi elds of application of the high-effi cient automatic and semiautomatic submerged arc welding instead of manual one, to rationalization of welded structures and industrialization of their manufacture. The Institute staff was the fi rst in the world to realize the automatic welding of sheet structures directly under the site conditions. The works of this period made a decisive effect on the rates of the after-war reconstruction of in-dustry, development of modern production of building metal structures, high-reliable products of heavy, transport, chemical, power engineering and other branches of machine building.

One of the most important achievements of the Institute at the beginning of the 1950s of the XX century was the development of the new process of joining the thick-walled parts and billets. i.e. the electroslag welding. This process made radical changes in the manufacture of heavy frames, boilers, hydraulic units and other unique welded-rolled, welded-cast structures. Later, in collaboration with TsNIITmach and other organizations a method of CO2 arc welding was developed, found wide spreading in the industry and provided the great growth in the lev-el of mechanization of welding jobs. The further development of the arc welding with consumable electrode was the development of the process and equipment of a pulsed-arc welding, welding with fl ux-cored wire and in mix-tures of active and inert gases.

Since the 1950s of the XX century the searching investigations and experimental developments were widened by the initiative of academician Paton B.E. on the application of welding heat sources for producing metals and alloys of extra-high quality and reliability. This branch of engineering was named as a special electrometallurgy and now it is the second main trend in the Institute activity. The works of the staff in this new branch was the next step in the development of the modern high-quality metallurgy. At the beginning of the 1980s of the XX century one more scientifi c direction was formed: thermal spraying of protective and wear-resistant coatings. Over the re-cent years the unique technologies of welding live tissues and vessels have been developed, which passed tests on animals and used now in surgery operations on humans.

The E.O. Paton Electric Welding Instituteof the National Academy of Sciences of Ukraine

Catalogue of scientifi c-technical products

In 1969 the pilot-cosmonaut Kubasov V.N. was the fi rst in the world to realize the unique experiment on weld-ing by electron beam, plasma and consumable electrode using the unit «Vulkan», designed at the PWI, on the board of spaceship «Soyuz-6». So, the start was made for the space technologies having a large importance in exploration of space. In 1984 the cosmonauts S.E.Savitskaya and V.A. Djanibekov performed for the fi rst time in the world the experiments on welding , brazing, cutting and coating in open space using a versatile hand elec-tron beam tool VHT, designed and manufactured at the PWI. Later, the integrated experiments were performed in open space for deployment of 12 m truss structure, accompanied by welding and brazing of its separate units using VHT, and two 15 m truss structures were deployed for solar batteries of the technological module, docked to orbital station «Mir».

The system investigations of physical-metallurgical peculiarities of fusion welding of different metals and alloys, made at the Institute, have a fundamental importance. The processes of weld metal crystallization were studied, nature of its structural and chemical heterogeneity was established, mechanism of porosity and crack formation was discovered and measures of their elimination were found. The results of these investigations are the theoret-ical bases of development and improvement of welding and surfacing consumables.

The E.O.Paton Electric Welding Institute (PWI) of the National Academy of Sciences of Ukraine is the scientifi c-tech-nical complex by its structure. It includes: experimental design-technological bureau, experimental workshops, three pilot plants, several engineering centers. In all subdivisions of the Institute the staff is about 3500 persons, 1700 of them are working at the Institute proper. The scientifi c potential of the Institute is 300 staff scientists, including 8 acade-micians and 5 correspondent members, 72 Doctors and more than 200 Candidates of Techn. Sci.

The main directions of the Institute scientifi c activity: ■ integrated studies of nature of welding, brazing, spraying and related processes, creation on their basis of

new high-effi cient technologies, equipment and materials; ■ study of strength and service properties of welded structures, development of principles and fundamentals of

their designing, improvement of reliability, durability and service life; ■ automation and mechanization of processes of welding and related processes; ■ creation of new technologies and equipment of electrometallurgical production of extra-quality alloys and

composite materials and products of them.Over the years of the Institute activity its staff members received more than 6500 author’s certifi cates, about

2600 patents of Ukraine, Russian Federation and foreign patents, more than 150 licenses were sold to the USA, Japan, Russia, Sweden, France, China and other countries. More than 60 developments, realized and imple-mented into the national economy by the Institute staff members in collaboration with industrial organizations were awarded the Lenin and State Prizes in the fi eld of science and technology, prizes after the names of out-standing scientists of Ukraine and other prizes.

The Institute has wide international relations with leading centers of welding in Europe, USA, Asia, carries out a large work in the fi eld of organizing the joint research works and is the member of the International Institute of Welding and European Welding Federation. On the Institute facility there are: International Council on welding and related processes of CIS countries; Scientifi c Council on new materials of the International Association of Academies of Sciences, International Association «Welding», International Association «Interm», Council of So-ciety of Welders of Ukraine and E.O. Paton Chinese-Ukrainian Institute of Welding.

3Catalogue of scientifi c-technical products

TECHNOLOGIES AND EQUIPMENT

HIGH-SPEED ELECTROSLAG WELDING OF THICK-PLATE METAL WITHOUT NORMALIZATION OF WELDED JOINTS

When the traditional electroslag welding is used, the separate regions with a reduced resistance to brittle fracture as compared to that of parent metal are observed in the welded joint. As a rule, the heterogeneity of structure and me-chanical properties in these regions is eliminated by the application of postweld high-temperature treatment, for example, normalization. However, it leads to an abrupt increase in cost of the product manufacture.

The new method of a high-speed electroslag welding with an automatic com-mutation of current connectors to a group of electrodes and edges of welded joints and equipment for its realization have been developed, allowing producing quality welded joints without postweld high-temperature treatment.

To realize the new technological process of electroslag welding, the automat-ic two- and three-channel commutators of alternating (combined) current (current of up to 6 kA, 1 …17 Hz frequency, 2…6 on-off time ratio) and two-channel di-rect current (1.5 kA current, 10 Hz frequency, 2…6 on-off time ratio) have been designed, which are compatible with existing serial power sources. Controllers and sensors of metal pool molten metal level, voltage stabilizers at the slag pool, digital meters of electrode wire feed speed, have been designed, having no ana-logues in the national and foreign engineering.

The new technological process makes it possible to weld steels of 40…150 mm thickness at high effi ciency ( 3.0–6.0 m/h welding speed) and lower specifi c energy input (4...6 times reduced as compared with that of conventional conditions) at 3…4 times decrease of power consumption as compared with conventional ESW for the above-mentioned thicknesses.

Field of application. Welding of thick-plate steels in shipbuilding, reactor construction, boiler and converter production, hydro-engineering works, cryogenic engineering, cement machine building (steels of 25KhN3MFA, 16GNMA, 20K, 22K, 16GS, 09G2S, 03Kh20N16AG6, 10KhSND, 25L, 25GSL, 35L and other types), as well as control of structure of welds in electroslag welding of copper, titanium alloys.

Pollutions of toxic elements are 3..4 times reduced as compared with conventional electroslag welding.Equipment has been implemented at the number of metallurgical and machine-building plants of CIS, includ-

ing «Ukrtsemremont» (Zdolbunov city) for welding of kiln furnace bands, JSC «Sibenergomash» (Barnaul city) for welding of boiler fragments of 90, 110 and 150 mm thickness, made of steels 16GS, 22K and 16GNMA, as well as in repair of body of blast furnace DP-9 and assembly of converter body at «Krivorozhstal» Metallurgical Works.

TECHNOLOGY AND EQUIPMENTFOR ELECTROSLAG WELDING OF BUSBARS OF ALUMINIUM

ELECTROLYSERS UNDER CONDITIONS OF SERVICE AND POWERFUL MAGNETIC FIELDS

At present, when assembling the busbars in electrolysis shops the welding-on of outlet chutes to busbars is one of the most complicated and labor-intensive operations. Welding is realized under the conditions of effect of high-power magnetic fi elds, infl uencing negatively the welding process stability. Moreover, the work with busbars is performed without switching-off of the technological current.

The technology of electroslag welding (ESW) with consumable wire electrode is offered for mastering, allowing making welding of joints of sections from 60×800 mm up to 140×1000 mm under the conditions of operating shops and powerful magnetic fi elds. A rolled aluminium wire of diameter of up to 10 mm and fl uxes, not containing lithium, and which are avail-able in suffi cient amounts at any enterprise of this profi le, are used as welding consumables. Specialized equipment, rigging and technological processes are designed and developed to suit the conditions of the Customer.

ESW can be performed both at the de-energized area of busbar and also on the busbar, along which the tech-nological current of up to 7 kA is passed. Inspection of electrotechnical properties of joints showed that the volt-age drop (allowable to 20 mV) in joints, produced by ESW, was 5.2 mV ( while in manual arc welding the voltage drop is 30 mV), and it is 4.8 mV at a monolithic busbar.

The given technology allows decreasing the losses of electric power in welded joints, reducing the expenses for manufacture and repair of aluminium busbars, improving the welding process effi ciency and quality of aluminium welded joint of above-mentioned sections, improving greatly the labor conditions of the welders.

A number of foreign companies resumed the application of mechanical joints in the busbar design. At alumini-um plants of CIS the manual arc welding with carbon electrode and method of fi lling with a molten aluminium are used. All the applied technologies do not provide a stable required quality of busbar joints.

New technology of ESW has been successfully tested at maximum magnetic fi elds (vertical component of a magnetic in-duction was 30·10-4 T) using laboratory equipment at operating shops of aluminium plants of the Russian Federation.

Completion of repair of blast furnace (inside view) at

«Krivorozhstal» Works. As-welded part of wall is shown.

4 Catalogue of scientifi c-technical products

TECHNOLOGY AND EQUIPMENT FOR ELECTROSLAG CASTINGOF SHAPED HIGH-STRENGTH STEEL BILLETS

Electroslag cast metal is superior to conventional forged and rolled metal in duc-tility and toughness, anisotropy of these properties, and in consistency of strength characteristics. High mechanical properties of the electroslag cast metal led to the development of a number of technological processes and equipment for produc-tion of super critical shaped billets by the electroslag casting method. A number of processes for electroslag casting of shaped billets are available:

■ casting into fi xed shaped split moulds, including by topping up using some pre-fabricated elements during the casting process;

■ special technology for casting into movable one-piece moulds; ■ centrifugal casting into steel moulds made from metal melted in a refractory cru-

cible by the electroslag method.Electroslag shaped casting by the above methods, as well as the process of con-

ventional electroslag remelting, provides purifi cation of metal from gases, non-me-tallic inclusions and sulphur, while solidifi cation of the metal occurs in a directional manner, and the front of the solidifying metal is continuously topped up with liquid metal. Therefore, the electroslag metal is characterised by high purity and density.

The commercially manufactured equipment and fi xture are available to produce shaped castings by all of the above methods. Substantial industrial experience has been accumulated in using the above methods for production of various cast-ings with a weight of 100 to 2000 kg from steels of the KT50 – KT110 strength grades. The metal of such castings inspected to continuity by the ultrasonic test method (GOST 24507-80) is characterised by increased ductility, toughness and brittle fracture resistance (see the Table), this making it possible in many cases to replace expensive forgings by much less expensive and much higher quality parts of electroslag shaped castings.

Electroslag shaped castings can be applied both instead of conventional cast-ings to improve quality and reliability of various machine and mechanism parts, and instead of shaped forgings to improve reliability and reduce manufactur-ing costs. First of all, the electroslag shaped castings are used to manufacture big bodies of stop valves for pressure steam pipelines, bodies of gates and oth-er components of pressure Christmas trees for oil and gas wells, high-alloy steel fl anges for chemical equipment, billets of large gears and gear shafts, as well as many other critical engineering parts.

Electroslag shaped castings are characterised by a high quality of metal, which cannot be achieved when using conventional forging or casting. Metal of the electroslag shaped castings has ductility and toughness that are 2-3 times higher than metal of conventional castings, and 1.5-2 times higher than metal of forgings. Moreover, it has a 2-3 times lower anisotropy of mechanical properties, compared to the forged metal. Owing to this fact, components of the electroslag cast metal can be employed in super critical units operating under heavy loads, which otherwise may lead to brittle fracture. The electroslag cast metal is more resistant to this type of fracture than the conventional forged metal.

The developed technological processes and equipment provide much better working conditions, compared to conventional casting and forging, and exclude the use of manual labour. Requirement for the attending personnel is minimal, production is practically non-waste, and there is no need for very expensive, often unique press-forging equipment. The productivity is up to 200 kg/h per unit.

Table. Mechanical properties of metal of Christmas tree body billets(after heat treatment) made by electroslag casting

Type of billet σ0.2, MPa σt, MPa σ0.2/σt, % δ, % ψ, % KCU, J/cm2

Casting* – steel 34CrMo4

363-396376

651-729695

51.1-55.854.2

6.0-20.011.1

10.0-27.117.7

16.3-25.821.1

Forging* – steel 34CrMo4

466-496483

704-782735

62.6-69.165.8

18.0-25.022.3

31.1-62.048.8

28.5-131.695.6

ESC** – steel35XM

548-588568

700-746721

78.2-78.878.5

17.7-23.320.0

63.4-69.566.4

146-206179.3

Steel 34CrMo4 is analogue of steel 35XMMinimal and maximal values are given in the numerator, and arithmetic means are given in the denominator*Data of «Cameron» Company: «Steel forgings instead of steel castings» / Catalogue of the «Cameron» Company // «Neftegaz-90» Exhibi-

tion**Data of IF «Elterm» obtained from testing 24 billets

Fragments of the process of centrifugal casting of shaped billet

in metal mould by using high-quality liquid metal melted by the electroslag method in refractory

crucible:a – completion of the crucible melting process; b – centrifugally cast shaped

billet of straight-through gate body with Dn 50 mm for a pressure of

up to 70 MPa

a

b

Straight-through Dn 80 mm and 70 MPa gate for control heads of

oil and gas wells


ELECTRIC ARC CONSUMABLE NOZZLE WELDINGThe electric arc welding with consumable nozzle (EWCN) is the new technological process developed at the PWI for

joining steel parts of 16-250 mm thickness. Being the variety of a vertical electric arc welding with a forced weld formation, it is char-acterized by using a special electrode with an insulating coating, arranged in a gap between the edges being welded and having a role of a consumable nozzle, through which a feeding of weld-ing wire (from one to four) is realized during the welding process. Welding is performed into a narrow gap (8-20 mm) without edge preparation, thus providing the high effi ciency of the process (de-position coeffi cient reaches 22-24 g/A·h) at moderate specifi c heat input (25-50 kJ/cm2).

Two variants of the process have been developed (Figure 1): with a fi xed nozzle for welding parts of 16-80 mm thickness and with a movable nozzle for welding of a compact section of thick-ness up to 250 mm. In the fi rst variant the width of electrode is equal to thickness of parts being welded, in the second variant a narrow electrode is used, making reciprocal movements (os-cillations) in a gap between the edges being welded to provide their complete penetration.

Specialized equipment and welding consumables have been designed for this method, allowing producing quality welded joints, including those in welding in site and fi eld conditions.

The method of welding was patented in Ukraine (Patent No.68361) and Russia (Patent No.2219021).

The advantages of electric arc consumable nozzle welding are as follows:

■ high effi ciency – up to 20 kg/h of deposited metal; ■ capability to weld thick metal for one pass; ■ minimum expenses for edge preparation, grooving is not required; ■ capability of narrow-gap welding; ■ high level of process mechanization; ■ simplicity and mobility of equipment that allows the process to be

used in site and fi eld conditions.On the basis of the above-mentioned process, the technology of welding

cathode pins (blooms) of electrolyzers of 90x180, 80×220 and 115×230 mm section was implemented at aluminium plants of Russia (more than 16 000 welds were welded). Figure 2 shows the ADPM type machine for welding blooms under the site conditions, which can be also used in manufacture and repair of metal structures of electrolyzers (housings), including conditions un-der the effect of magnetic fi elds in electrolysis shops.

As to rail welding, the machine of ARS type has been designed. Weld-ing is performed by a moving nozzle, making reciprocal movements of a variable amplitude, owing to which a complete penetration of edges being welded is realized over the full sec-tion of the rail. Characteristics of the ARS machine are given in Table 2, and mechanical properties of weld-ed joints are given in Table 3.

Field of application: ■ manufacture of industrial-pur-

pose metal structures of low-car-bon and low-alloy steels of 16-80 mm thickness;

■ welding of parts of a compact section in machine building, in-cluding those of a variable sec-tion of up to 250 mm thickness;

■ welding of butts of differ-ent-purpose rails (railway, tram, crane) in construction and repair of tracks.

Welding with fi xed nozzle Welding with moving nozzle

Fig.1. Variants of electric arc consumable nozzle welding

Fig. 3. Machine ARS for rail welding

Fig.2. Machine ADPM for welding of blooms in mounting and repair of electrolyzers


The process allows 2–4 times increase in productivity of works as compared with traditional methods of welding.Table 1. Technical characteristics of machine ADPM

Rated voltage of d.c. mains, V(Machine is supplied from welding source connector) 27/36

Rated welding current, A at duty cycle =100% 800Diameter and amount of wires, mm × pc 2.4 × 2Ranges of adjustment of electrode wire feed speed, m/h 50 - 300Speed of electrode movement, m/h 4 – 12Electrode travel, mm 200Range of thicknesses being welded, mm- with a fi xed nozzle- with a moving electrode

16 – 40 4 – 250

Dimensions L×W×H, mm 990×500×930Mass of machine without wire, kg, not more than 65

Table 2. Technical characteristics of machine ARSRated voltage of d.c. mains, V

(Machine is supplied from connector of welding source FORSAZh -500))27/36

Power, consumed by source, kVA, not more than 20(3×380V)

Rated welding current, A, at duty cycle = 100% 400

Diameter of used fl ux-cored wire, mm 2.4

Ranges of adjustment of electrode wire feed speed, m/h 50 – 300

Speed of electrode movement, m/h 4 – 12

Electrode travel, mm 180

Frequency of electrode oscillations, Hz 0/5 – 2

Amplitude of electrode end oscillations, mm 0 – 20

Dimensions L×W×H, mm 1320×520×850

Mass of machine without wire, kg, not more than 60

Table 3. Mechanical properties of welded joint of rail R65Hardness of weld metal 280 – 320 HB

Tensile strength of weld metal 850 – 900 MPa

Results of tests for static bending:-fracture load-bending

1500 – 1650 kN16 – 22 mm

MACHINES FOR FLASH-BUTT WELDING OF UNMEASURED ROLLED METALThe new technology of fl ash-butt welding of products of large-section rolled stock (up to 25000 mm2) makes it

possible: ■ to reduce greatly the tolerances for fl ashing; to realize the fl ashing process at minimum specifi c power; ■ to guarantee the high and stable quality of welded joints owing to more smooth macrorelief of fl ashing surface; ■ to increase the production effi ciency of metallurgical plants by 15% without the increase in energy consumption.

The welding machines for realization of the given technology have the self-adjusting systems of control and computerized systems of welding parameters monitoring. Technology has been patented.

Machine K1003 for fl ash-butt welding of rolled metal products of section up to 25000 mm2 and with auto-matic fl ash cuttingTechnical characteristics

Rated voltage of mains, V 380

Frequency of mains voltage, V 50

Consumed power of complex, not more than, kVA 400

Rated secondary voltage, V 7.916

Rated welding current at duty cycle = 40%, A 56200

Maximum welding section, mm2 25000

Maximum clamping force, kN 2500

Maximum upsetting force, kN 1000

Time of welding, s 180

Effi ciency, welds/h 10

Mass of welding machine, kg 15000


Machine K1000 for fl ash-butt welding of rolled metal products of section up to 15000 mm2 and with automatic fl ash cutting

Technical characteristicsRated voltage of mains, V 380

Frequency of mains voltage, V 50

Consumed power of complex, not more than, kVA 200

Rated secondary voltage, V 7.916

Rated welding current at duty cycle = 40%, A 26200

Maximum welding section, mm2 15000



Time of welding, s 130

Effi ciency, welds/h 15


Conditions of welding of large-section rolled metal products

Product being weldedCross-section

areaS, mm2

Tolerance for fl ashing and upsetting

L, mm

Time of weld-ing T, s

Current,I prim., A

Specifi cpower P,VA/mm2

Power perone weldQ, kW/h

Rail R65 8600 30 90 400 20 2.8Rolled metal ofØ 150mm 17660 35 120 500 10 4.5Rolled metal of 150 mm square 22500 35 130 600 10 6.5

Chemical composition of steels being weldedC Mn Si S P Cr Ni Cu V

10 0.07-0.08 0.35-0.65 0.17-0.37 - - 0.15 -20 0.17-0.24 0.35-0.65 0.17-0.37 - - 0.2545 0.42-0.5 0.50-0.80 0.17-0.37 - - 0.25

36G2S 0.3-0.4 1.5 0.40-0.70 0.035 0.035 0.3 0.25 0.2535G2F 0.3-0.4 1.4 0.17-0.37 0.030 0.030 0.3 0.30 0.30 0.12

a b

Flashing surfaces before upsetting using classic (a) and new (b) technologies

Macrosection of welded joint using new technologyShop area for welding unmeasured rolled metal at

«Metal Steel Krivoy Rog» Works

Welded rolled metal of square section 150×150 mm

Welded rolled metal of 150 mm diameter


TECHNOLOGY AND EQUIPMENT FOR AUTOMATIC CONTINUOUS FLASH BUTT WELDING OF PIPELINES

The technology and equipment for continuous fl ash butt welding of pipelines from 57 to 1420 mm diameter were developed. Over 70000 km of gas and oil pipelines, including those under conditions of the Extreme North of Russia, deserts of Iraq and Turkmenistan, were welded using these technologies. The technologies of fl ash butt welding have the following advantages:

high and stable quality of welded joints in compliance with requirements of international standards; ■ high productivity – 6-12 welds per hour; ■ no welding consumables are required; ■ ends of pipes do not need any special preparation for welding; ■ welding process is fully automated which provides stable reproduction of preset conditions; ■ the computerized system for monitoring of welding conditions provides high reliability of joints quality evalu-

ation.The technology and equipment are designed for automatic fl ash butt welding of pipes of different categories of

strength and chemical composition during construction of pipelines of different purpose of 57…1420 mm diame-ter including in construction of offshore and underwater pipelines.

INNOVATIVE TECHNOLOGIES AND EQUIPMENT FOR PULSED FLASH BUTT WELDING OF RAILS OF MODERN PRODUCTION

PWI developed the innovative technology of fl ash butt welding using pulsed fl ashing, considerably increasing the effi ciency of heating process. At the similar preset capacity of power source the current value in welding cir-cuit in pulsed fl ashing is 1.8…2.5 times higher than in continuous fl ashing and is maintained at the constant level during the whole fl ashing period. The tolerance for fl ashing is 1.5…2.5 times reduced. Depending on the preset values of power the qualitative welding of rails at the pulsed process can be performed due to a change of heat period within the wide ranges. It gives possibility to select the most optimal thermal cycles in welding of rails of the steels of different chemical compositions and properties.

Advantages of the method: ■ reduction of welding period and losses of metal for fl ashing by 2-3 times ■ reduction of power consumption by 1.5 times; ■ increase of values of strength, ductility and fatigue of welded rails of different categories; ■ reduction of gas-forming evolutions by 10 times. The technology is protected by the patents of Ukraine, Rus-

sian Federation, USA, England and China. ■ On the basis of the developed technology the production of new generation of suspended welding machines

of the type K920, K922, K930 and those of stationary type K1000, K1100 (Fig. 1 – 5) was mastered at the OJSC «Kakhovsky Electric Welding Equipment Plant», equipped with computerized systems for control of process or/and

Flash butt welding machine K813 Flash butt welding machine K584M

Flash butt welding machine K805 Flash butt welding machine K700-1


basic welding parameters. More than dozen of innovations were used in this equipment protected by the inter-national patents in the fi eld of welding, systems of control and programming of welding processes and also de-sign of main assemblies of welding machines differing in original arrangement of mechanical elements, welding circuit, use of quick-operating hydraulic drives and new principles of rails alignment. The quality of welded joints meets the requirements of the international standards.The mobile rail welding complexes (Fig. 6) were designed. Over the recent years more than 30 stationary ma-

chines of the type K1000 and more than 45 suspended rail welding machines were manufactured and delivered to different countries (Russian Federation, USA, Canada, Austria, England, China, Singapore, Thailand, Malay-sia, Taiwan, Slovakia).

Fig. 1. Suspended fl ash butt rail welding machine K920

Fig. 2. Suspended fl ash butt rail welding machine K922

Fig. 3. Machine K930 for welding of railsof infi nite length

Fig. 4. Machine K1000 for welding of rails under stationary conditions

Fig. 5. Machine K1100 for welding of rails under stationary conditions

Fig. 6. Mobile fl ash butt rail welding complex


TECHNOLOGY AND EQUIPMENT FOR FLASH BUTT WELDING OF RAIL FROGS USING PULSED FLASHING

The technology for fl ash butt welding of high-manganese steel with rail steel through the insert of austenite steel was developed at the PWI.

The specimens of rail frogs with rail endings passed the fi eld tests which proved high quality of welded joints.The developed welding technology and specialized machine K924M allow producing joints without application of

auxiliary heat treatment.

Technical characteristics of the specialized fl ash butt welding machine K924M

Power capacity, at duty cycle = 50% kVA 180



Maximum welded section, mm2 15000


TECHNOLOGY AND EQUIPMENT FOR FLASH BUTT WELDINGOF CUTTING TOOLS

The technology and equipment for fl ash butt welding of tool steel with structural steels for manufacture of bi-metal metal-cutting tool were developed at the PWI (For example, high-speed steel of grade R6M5 with structur-al steels 45, 20Kh, 40Kh, etc.)

The technologies of fl ash butt welding and equipment guarantee manufacture of cutting tool with butt joints of practically equal strength with that of base metal.

The welding process is fully automated, has a program control and control of welding condition parameters in real time.

Fig. 1. General view of area with welded-in rail endings

Fig. 2. Specialized machine K924M for welding of rail frogs with rail endings

Specimens of welded bimetal tools


The specialized machines were developed and universal machines for fl ash butt welding K802, K793, K724A, K838 were modifi ed, which allow welding blanks of a tool with section from 7 up to 8000 mm2.

TECHNOLOGY AND EQUIPMENT FOR MIAB WELDING OF PARTS OF HOLLOW AND SOLID SECTION

The innovative technology and equipment for Magnetically Impelled Arc Butt (MIAB) welding of tubular parts of diameter from 6 to 219 mm with wall thickness of up to 10 mm, and also parts of solid section of up to 32 mm diameter were developed at the PWI.

The principle of the developed technology is based on physical phenomenon of electric arc movement in trans-verse magnetic fi eld generated by permanent magnets between the ends of parts being welded. Due to relatively high speed of arc movement the redistribution of arc power along the whole surface of parts occurs. As a result, the relatively uniform heating of part ends being welded occurs. The joint is formed at compression and plastic deformation of welded parts (upsetting). The arc gap between the parts in the process of welding is maintained in preset limits, at which maximum possible heat is provided, generated into the ends of parts. Considering that MIAB welding process is running without use of welding consumables and shielding gases, the application of this process is economically rational.

Basing on the developed technology of MIAB welding the manufacture of new generation of universal equip-ment for different fi elds of industry was mastered.

FLASH-BUTT WELDING OF PRODUCTS OF ALLOYS BASED ONALUMINIUM, MAGNESIUM, TITANIUM, STAINLESS

AND HEAT-RESISTANT STEELS AND ALLOYSThe technologies and equipment for fl ash butt welding of different products of alloys based on aluminium, mag-

nesium, titanium, stainless, heat-resistant steels and alloys with cross section area of up to 40000 mm2 including rings of pressed profi les, plates and forged pieces of high-strength alloys based on aluminium of more than 500 mm diameter, as well as sheets of up to 2000 mm width, up to 50 mm thickness and longitudinal welds of shells of these sheets of more than 2000 mm diameter were developed.

The fl ash butt welding can be applied for almost all high-strength aluminium alloys.It provides:

Macrosection of welded joint of pipe of 32x3 mm diameter.

Time of welding is 4.2 s.

Macrosection (left) and welded joint of pipe of 219x8 mm diameter.Time of welding is 36 s.

Welding-on of two connections of 32 mm diameter to the gas meter

casing. Time of welding of connection is 1.7 s.

Welded joint of pipe 30x30x2 mm after bend tests (left); time of welding is 3.9 s;

welded joint of 50x35x2.5 mm pipe ; time of welding is 4.7 s

Welding of reinforcement rodof 32 mm diameter.

Time of welding is 34 s.


■ strength coeffi cient of welded joints of not less than 0.9 of that of base metal; ■ high precision of geometrical dimensions of large-section parts (the deviation around the perimeter is ±1

mm), no stresses; ■ high productivity (welding time is 2.0–3.0 min); ■ no need in welding consumables

The developed technologies and equipment are designed for manufacture of rings and shells of bodies of rock-et and aircraft engineering and parts of engines. They can be also applied both for welding products like wheel rims of bicycles, motorcycles, automobiles, different elements of building structures, as well as for welding of large-size objects for chemical, food, metallurgy industry, use in ship building, etc.

TECHNOLOGY AND EQUIPMENT FOR FLASH BUTT WELDINGOF BAR REINFORCEMENT

To mechanize and automate the welding and auxiliary processes the technology and equipment for welding of high-strength and heat-hardened bar reinforcement were developed applied in building structures of pre-cast and monolithic reinforced concrete.

The fl ash butt welding technology guarantees producing of butt joints of reinforcement of grades A240…A1000 practically of equal strength with that of the base metal.

The welding process is fully automated and has program control of welding parameters.The specialized fl ash butt welding machines of the types K724A were designed and the universal machine

MSO-606 was modifi ed.The equipment can be applied autonomously or as a part of automated lines for welding reinforcement, as for

example line K777, and also for manufacture of mobile complexes in welding of reinforcement under the condi-tions of building sites.

The technology and equipment for fl ash butt welding of reinforcement is applied at the enterprises of building industry and metallurgy plants for production of bar reinforcement of measured length, in preparation of monolith-ic concrete reinforcement, and also to create areas for reinforcement welding using mobile complexes under the conditions of building sites.

Flash butt welding of frame ringsin the machine K393

Flash butt welding of shells in the machine K767

Flash butt welding machine K813 as a part of mobile complex

Macrosectionof welded jointFlash butt welding machine K724A

in the production line


Machines for fl ash butt welding of reinforcement bars

Type of machine

Maximum section being welded, mm2

Upsetting force,

kNCapacity of welding

transformer, kVAEffi ciency,

welds/h Dimensions, mm Mass, kg

МСО606 2000 63 100 40 2580×1670×1380 2400

К724А 4000 160 112, 5 40 2800×930×2280 4700

К617 4000 160 150 40 1850×1600×1450 3660

К812-2 1500 70 35 60 1150×930×760 1065

К838 8000 320 350 30 2050×1500×2350 6500

К813 3000 120 70 12 1622×920×880 1300

К355А 14000 40 150 12 1846×1100×1520 3500

PULSE TECHNOLOGIES FOR HARDENING OF TOOLSAND PARTS OF MACHINES

These technologies are applied for alloying (N, C, Mo, W, Cr, etc.) and formation of nanocrystalline structure of surface layer of products of alloys based on iron, aluminum, titanium and hard alloy, in metallurgy: mill rolls, blades, saws, rollers and drums; in machine building: tool for processing of: metals, timber, plastic, parts of stop valves, rod of hydraulic jacks, parts of hydropneu-matic drive, end sealing, gears, etc.; in aircraft construction: parts of jet air-frame.

Advantages: ■ improvement of wear resistance, an-

tiseizure resistance, strength, antifric-tion resistance, corrosion resistance, heat resistance;

■ service effi ciency of products is 3-6 times increased;

■ technology is realized without heat-ing of product, changes of its geometric sizes and roughness.

CUMULATIVE-DETONATION TECHNOLOGY FOR DEPOSTION OF COATINGThis technology is applied for deposition of coating of powder alloys based on ceramics, copper, iron, titanium

and hard alloys based on metal carbides.In metallurgy: protective coating on the plates of mould, heat-resistant coatings on the surface of rollers in an-

nealing furnaces for sheet steel, coating of drums, rollers, etc.In machine building: stop valves, blades of fans, compressors and pumps, surfaces of shafts, rods of hydrau-

lics and cylinders, end seals, etc.

Automatic equipmentfor hardening the surface of metallic

products and tools

Installation for hardeningof hard-alloy mill rolls

Mill rolls Cast-iron calibers

Blades and trimming matrices

Stamps and punches

Blades for beet and meat

Steel saws Flat knives Drawing tools and shaping cutters


In aircraft construction: parts of jet airframe, guiding rods, etc.

Advantages:Low temperature effect on the product; ■ High adhesion of coating >100 MPa; ■ Low porosity of coating <1%; ■ Low roughness of coating; ■ High metal utilization factor 90%

PLASMA METALIZATION OF AXLES OF RAILROAD TRANSPORTAt the railroad transport hundreds of axles of wheel pairs are rejected due to presence of defects and wear of

journals, their scorings, risks, etc., the restoration of which can bring a considerable economic effect.PWI has developed the innovative technology of plasma metalization in the medium of argon using current-

conducting wire-anode, serving as an initial material for coating formation.The argon arc plasmatron is applied with tungsten cathode and air cooling. Use of wire as a sprayed an-

ode increases the process effi ciency as far as plasma energy is used to form a coating instead of heating the plasmatron.

The fl ow of argon plasma is axially blown with air around the circumference, at the same time cooling down the plasmatron, forming the fl ow, shape and composition of plasma.

The mode of blown fl ow is selected so that to provide conditions to make the contours of visible cone of outgo-ing plasma almost parallel which evidence of inconsiderable mixture of plasma with cooling air.

Due to a high speed of outcoming fl ow the zone with maximal argon content is spreading to the considerable length of up to 150…200 mm, which allows producing coating in it without signifi cant oxidation.

As a material for coating the wires of steel 65G, 70, 20Kh, 30 KhDS and fl ux-cored wires were used.The innovative technology allows decreasing the porosity in coating down to 2…5%, eliminating oxides and

also improving adhesion of produced coating with substrate up to 40…60 nm.

PLASMA POWDER CLADDING OF POWER, CHEMICALAND GENERAL ENGINEERING PARTS

The key advantage of plasma powder cladding is a low penetration of the base metal, as well as the pos-sibility of providing a high-quality metal with the required chemical composition and properties already in the fi rst deposited layer. This is particularly important in the case of using expensive nickel- or cobalt-base clad-ding consumables.

Spherical valve Wedge valve Wedge bushing Flat valve Mill roll Guiding roller Pump blades

Examples of parts with coating based on WC-Co-Cr and Cr3C2-NiCr

Process of plasma spraying of coating onto railroad axle in the installation KT-088

General view of the installation KT-088 for wheel pair axle journal restoration


Plasma powder cladding of power, chemical and general engineering parts is implemented by using machines equipped with modern control systems based on industrial computers, which provides a substantial improvement of quality, stability and reliability of the cladding process. The machines comprise a new design of the plasmatron with a lateral feed of the powder. This increases the process productivity, decreases losses of the powder and widens the process application fi eld, which is attributable to the possibility of depositing powders of magnetic iron-base alloys.

The machines meet the state-of-the-art requirements for environmental safety. They are equipped with a stand-alone water-cooling unit and protective chamber, which provides a complete protection of workers from the harm-ful effect of radiation of the plasma arc, as well as gases and dust emitted during cladding.

The modular principle allows performing the high-quality cladding on other parts by replacing two or three modules and a control program, e.g. internal combustion chamber valves of different standard sizes, knives for hot and cold cutting of metals and non-metallic materials, etc. This considerably widens the application fi eld for the plasma powder cladding machines.

Specifi cations ■ The computer-control system is intended for programmed control of operation of the machine. It provides

performance of a repeatable cycle of operations on loading, fi xation, cladding (including control of the process mode parameters) and unloading of billets in cladding of a series of similar-type pieces.

■ The plasmatron of a new design with lateral feed of the powder provides the pilot arc current of up to 40 A, main arc rated current of 300 A, maximal current of 400 A, duty cycle of 100 %, and maximal deposition rate of 6 kg/h.

■ The powder feeder is designed for feeding the powder with particle sizes of 63-200 μm at a velocity of 5–100 g/min, the hopper capacity being 2 dm3, and duty cycle being 100 %.

■ The workpiece rotation mechanism provides the possibility of external program control of the workpiece ro-tation speed, rotation of workpieces with a weight of up to 20 kg and diameter of 30 to 200 mm, rotation speed ranging from 0.1 to 2.0 min-1, and duty cycle of 100 %.

■ The system for loading, fi xation and unloading of workpieces provides capture and placement of billets in the cladding position, capture of the clad billets from the cladding position and loading them into a container.

■ The system for the technological setting of displacements and positioning of the plasmatron provides a two-plane inclination of the plasmatron (±15°), positioning of the plasmatron in axes X and Y (up to 150 mm in each axis), and amplitude of oscillations of the plasmatron within a range of 2-25 mm at an oscillation frequency of 8-80 min-1.

■ The stand-alone cooling unit provides water pressure of not less than 0.3 MPa and water consumption of not less than 10 l/min.

■ The gas feed unit provides the following gas fl ow rates: plasma gas – 1–3 l/min, transportation gas – 4–6 l/min, and shielding gas – 10-20 l/min. The working gas is argon.The protective chamber provides complete protection of the personnel from the harmful effect of radiation of

the plasma arc, as well as gases and dust emitted during cladding.Confi gurationThe computer-controlled machine for plasma powder cladding consists of the following units: computer control

system, high-voltage power supply, main and pilot arc power supply, plasmatron, powder feeder, workpiece ro-tation mechanism, system for loading, fi xation and unloading of workpieces, system for setting of displacements and positioning of the plasmatron, stand-alone cooling unit, gas feeding unit, and protective chamber.

Machines for plasma powder cladding of iron-, nickel- and cobalt-base powders can be used as part of the au-tomatic production line or as a separate set.

EQUIPMENT AND TECHNOLOGYOF MICROPLASMA SPRAYING OF COATINGS

The equipment and technology of microplasma spraying can be used for deposition of coatings of powder and wires of different functional purpose on the parts and products in motor building, instrument industry, medicine,

electrical engineering industry and also to conduct different repair works.The installation of microplasma spraying MPN-004 is composed of the following

units: plasmatron, power source with autonomous cooling system, gas panel, powder hopper, wire feed device. For the design of plasmatron for microplasma spraying the Patent of Ukraine No2002076032 was received.

The installation allows depositing coatings of the following powders and wires: ■ Metals (aluminium, copper, nickel, titanium,

molybdenum, etc.); ■ Alloys (based on aluminium, copper, iron,

nickel, cobalt); ■ Oxides (aluminium, zirconium, titanium),

tungsten and chromium carbides; ■ Bioceramic materials (hydroxyapatite, trical-

ciumphosphate etc.).The distinctive feature of MPS is a small

size of spraying spot, amounting to 1 – 5 mm. The strength of adhesion of microplasma coat-ing on the base is up to 40 MPa.

Band of microplasma coating of NiCrInstallation MPN-004


Assembly of overlap-butt joints on operating pipeline

WELDING RESTORATION OF ALL-CAST ASSEMBLIES AND PARTSOF INDUSTRIAL EQUIPMENT

The specialists of PWI render services for the development of techni-cal solutions and technological processes of repair welding of large-size all-cast and welded structures of high-strength steels with increased car-bon content which accumulated damages in the process of long operation. In the basis of developments the results of carried out investigations at the PWI were used, directed to extension of life of damaged metal structures.

According to the results of analysis of state of metal and structure as a whole, the conclusion is made about the repairability of a product and tech-nological process of its restoration is worked out. The process of repair weld-ing is based on the modeling of technical methods of performance of resto-ration works. The selection of the optimal method of defects elimination and formation of edges of welded joint, welding method, welding consumables and method of non-destructive testing of repair joints is performed. The training of working personnel is performed and specialized repair teams are formed. After performance of repair works the conclusion about technical state of restored structure and recommendations on its inspection are given.

The expenses for restoration of mentioned products do not exceed 25% of their primary cost. After repair the equipment can operate in the project mode.

TECHNOLOGY FOR RECOVERY OF CARRYING CAPACITYOF DIFFERENT-PURPOSE PIPELINES AND WELDING OF BRANCH PIPES TO THEM UNDER SERVICE CONDITIONS

The pipeline transport of the CIS countries is in a diffi cult situation now because of progressing ageing of oil and gas pipelines. Half of the main oil pipelines have been in operation for 20-30 years or longer. More than 5 % of the gas pipelines have exhausted their specifi ed life (33 years), 25 % of the gas pipelines have been in service for over 25 years, and 38 % of the total length of the gas pipelines has been in op-eration from 10 to 20 years.

As shown by statistics, ageing of pipeline systems is accompanied by increase in the number of failures caused, fi rst of all, by corrosion pro-cesses and mechanical damages. This makes the problem of ensuring the effi cient and failure-free operation of the pipeline transport increas-ingly pressing. The key role in addressing it belongs to improvement of the existing methods and development of the new, more reliable and safe ones for performing repair and maintenance on main pipelines.

Operation of main pipelines very often involves the need to connect new consumers or new small and me-dium oil and gas fi elds, as well as the need to perform repair-and-renewal operations by replacing defective regions of a linear part of pipelines without interruption of transportation of a product. Keeping a pipeline in the active state while performing such repair operations is economically attractive, but it must be combined with the environmental safety.

We developed and apply the safe technologies for welding of branch pipes and welding repair of operating pipelines by the arc method without interruption of transportation of a product. On the one hand, these technolo-

Characteristic damages of frame of press of 105 MPa

Frame of press of 105 MPa(weight – 108 t, steel 35L)

Hydrocylinder of press 3-150(steel 35L)

Frame of heat-upsetting automatic machine AO-341(steel 35L)

Crack elimination

Restored unit


gies provide the high quality and reliability of welded joints in building-in of additional structural elements into the operating pipelines, and, on the other hand, they allow maintaining a failure-free operation of the transportation system and environmental safety.

The developed technologies are oriented to manual arc welding, as it allows performing welding and repair op-erations on the operating pipeline in any spatial position. These operations should be performed simultaneously and at a high quality. Therefore, it is necessary to carefully select the type of welding electrodes for each particu-lar case, depending on the pipeline steel grade, real state of the pipeline and its service conditions.

Whereas the problem of recovery of the carrying capacity of structures made from low-carbon and low-alloy steels with a comparatively low level of strength, which operate under extreme conditions of intensive cooling, can be considered solved in general, this is not the case of steels of an increased strength (σt – up to 450 MPa). Primarily, it concerns welding of pipe steels on active main ground-surface pipelines. Special reinforcing overlap elements were developed to ensure the appropriate operating reliability of the butt joints, and recommendations were worked out to transfer to the overlap-butt joints and the corresponding welding technology providing the re-quired thermal cycle. The use of the overlap-butt joints allows the transverse stresses in welding to be decreased two times, compared with the fi llet welds.

New process fl ow diagrams for joining structural components (sleeves, branch pipes, patches) to the pres-surised pipelines make it possible to substantially improve safety of the welding operations and reliability of the welded joints in operation, as well as protect the environment from pollution.

TECHNOLOGIES OF REPAIR-RESTORATION WORKSOF BRIDGE METAL STRUCTURES

They are intended to prolong the service life of critical building metal structures: bridges, cranes and subcrane girders, truss towers, pipes, etc.

The methods and technologies of repair and restoration of critical structures after long service were developed.Considering the conclusion about technical condition of the structures being in service, compiled according to

the results of their inspection and verifi cation calculations, the technology for their strengthening and repair is de-veloped. Here the causes of defects and damages formation are taken into account and methods to prevent their formation in the course of their further service are searched. The technological process of repair, resto-ration and reinforcement considers and regulates ap-plication of the basic and auxiliary materials, welding method, preheat, unload of structures before the re-pair, application of heat jacks, sequence of laying of weld beads, involvement of necessary testing-diag-nostic devices and other technology elements.

The methods of inspection and technology of strengthening and repair of metal structures were applied at the repair of the pedestrian bridge across the Dnieper river to the Trukhanov island, the road bridge after E.O.Paton in Kyiv, the passing across the dam of road transition in construction of «DneproGES» in Zaporozhye and other objects.

Reinforcement and repair of metal structures of automobile road along the dam at the erection of «DneproGES» in Zaporozhye (a – replacement of defective parts of lower girth of cross-bars; b – cross-bar after reinforcement and repair)

a b

Pedestrian bridge across the Dnieper river towards Trukhanov island in Kyiv with mounted devices for unloading of

suspensions during repair-restoration works


TECHNOLOGY FOR WELDING OF TUBULAR STRUCTURESThe welding technologies in manufacture and mounting of metal structures of pipes were developed. The ap-

plication of profi les of a closed section, in particular, round pipes, was justifi ed in their use instead of conven-tional sections performed of pair or single angles where fl exibility and torque resistance play a signifi cant role. The rationality of application of pipes grows at the pres-ence of increased architecture or sanitary requirements to the structures. The tubular structures comprise less metal, possess increased corrosion resistance (under the condition of sealing of inner cavity of pipes), prede-termined by relatively smaller surface area, subjected to corrosion, and better streamlining as compared to the profi les of open section and also by access for cleaning and painting. As a result the longevity of structures is in-creased and operational expenses are decreased.

The structures with application of pipes refer to the category of special. Therefore in the process of con-struction of structures the following characteristics are considered: purpose, peculiarities of the structure, ca-pacities of the plant-manufacturer and site organization.

WELDING, CUTTING AND EXPLOSION TREATMENTPWI has the test grounds for manufacture of special charges and performance of explosion operations, includ-

ing the unique tubular explosion chamber for 200 kg of explosives. The package of competitive technologies for explosion welding, cutting and treatment of metals used in many branches of industry for cutting out holes, res-toration of threaded holes, providing dimensional stability, etc. is available which found their demand among the customers both in Ukraine and abroad.

Construction of the International Exhibition Center in Kyiv. The site of roofi ng tubular structures, 20468 m2

Construction of terminal D in the Borispol airport

Methods for decreasing residual stresses in welded joints by explosion treatment

1-explosive charge2-weld treated

Scheme of explosion cutting process

Metal shell

Cumulativejet

Explosive charge

Explosive charge

Schematics of explosion welding (top) and joining of reinforcement bars using

explosion reduced sleeves (bottom)

Cladding metalExplosive charge

Base metalWave formation

1 – reinforcement bar, 2 – sleeve,3 – explosive charge


STRUCTURES OF TRANSFORMABLE VOLUME (STV)The structures of transformable volume (STV) allow solving the problem of application of shell structures in ser-

vice sites at which their manufacture and as-assembled delivery is not possible.STV on the base of thin-walled shells of titanium alloys and alloyed steels are capable to withstand the load at

suffi cient rigidity and to change within the wide ranges the longitudinal size at constant cross section. Basing on the methods of isometric changing the shape of thin load-carrying shells developed at PWI, a wide range of different-purpose STV of up to 4 m diameter and internal volume in working position of up to 40 m3 was devel-oped. Unfolding of structures is realized by creation of excessive pressure in their inner cavity, whose value does not exceeds 100 kPa for all types and sizes of shells.

Saddle-shaped cumulative charge for cutting out of branch holes in walls of pressurized main pipeline (left) and cumulative charge for remote

perforation of walls of gas and oil wells (right)

Explosion treatment for prevention of stress corrosion cracking of alumina

production tank facilities

Chamber for explosion treatment of materials with 200 kg capacity of

trinitrotoluol equivalent

Base metal of axle

Cladding bushing with thread

Macrosection of section restored using explosion welding of threaded hole

of load-bearing axles of wheel pair of railway car

Butt of reinforcement produced using explosion reduction of joining sleeve

Explosion treatment for ensuring of dimensional stability of water ducts at

hydroelectric pumped storage power station

Compact and transformed state of conical type structure obtained by uniting of large amount of equal transformable shells into a single structure using vacuum- tight welded joints; coeffi cient of transformation, i.e. ratio of longitudinal size before and after transformation reaches 40.


EQUIPMENT FOR ELECTRON BEAM WELDINGPWI is the world leader in development of: ■ equipment for highly stable EBW with a special fl ashless electron tube system; ■ defectless closure of welds for up to 250 mm steel; ■ EBW real-time monitoring by a network computer; ■ automatic system for real-time weld following.

Products: ■ installations with vacuum chamber volume from 0.1 up to 100 m3; ■ vacuum chambers of these installations were EB welded in an installation of 500 m3 volume; ■ installations for EBW of cut-in elements, longitudinal and circumferential butt joints of large-sized shells in lo-

cal vacuum; ■ installations with three guns for EBW of drill bits; ■ cylindrical-type installations for welding geared parts; ■ installations for continuous EBW of a bimetal strip for band saws and «steel-invar-steel» metal strips; ■ system of real-time weld following; ■ «Diabeam» EB analyzer; ■ mobile and stationary guns for EBW and power sources with breakdown protection system: 60 kV – 3, 15, 30

and 60 kW; 120 kV – 6, 18 and 120 kW.

EBW shop

Compact and transformed state of modifi cationof conical STV with a double shell, which can be usedin manufacture of tanks for storage bulky and liquid productsincluding substances with an increased chemical activity.

Long cylindrical STV on the base of hyperboloid corrugations, combining high compactness

with signifi cant transverse stability in unfolded state.


EB welded beam of a wing made of 100 mm thick high strength aluminium alloy

EB welding of an aircraft wing blank. Welded butt joint thickness is 65 mm

КL-132 machine was developed for EBW of jet engine components of SU-30 fi ghter at HAL Company plant

(Koraput, India)

Specialized machines KL-134 with welding gun sliding on the chamber upper cover and КL-154 machinewere developed for electron beam welding of titanium spherical tanks for space application

Electron beam welding of space facilities


Main activities: ■ research and development of EBW technology for aerospace industry, power engineering, high-pressure ves-

sels, automotive industry and shipbuilding, sensor and electronic engineering. Thickness of welded materials is from 0.5 up to 250 mm for steels and up to 400 mm for titanium and aluminium alloys;

■ development and manufacture of new and modifi ed EBW installations, their commissioning and training of service personnel.

KL-118 machine

With PWI involvement extensive application of elec-tron beam welding in manufacturing of ship gas turbine engine-power units was mastered at production com-plex «Zorya»-«Mashproekt» (Nikolaev, Ukraine). The same units are used as blowers for main gas pipelines. Welds are performed in 80 components and parts of one such engine by electron beam welding

KL-115 machine and welded component of a jet engine

КL-115 and KL-118 machines were developed for application in the US aircraft industry


MICROPLASMA SPRAYING OF BIOMEDICAL COATINGSThe technology of spraying of biomedical coatings on the surface of different endoprosthesis (endoprosthesis

of hip joint, dental endoprosthesis, intervertebral implants) was developed.This technology allows depositing: 1 – coatings of hydroxyapatite powder with the control of its phase composi-

tion; 2 – titanium coatings with controlled porosity (5 – 30%, size of pores is 50 – 150 μm) and minimal oxidation level (0.88 - 2.8 mass.%).

Endoprosthesis with microplasma biomedical coatings are applied in practice of endoprosthetics of hip joint (the certifi cate about the State registration No10725/2011 was issued basing on the whole complex of mechani-cal and biomedical tests).

Endoprosthesis with biocompatible coating

HIGH-FREQUENCY ELECTRIC WELDING OF SOFT LIVE TISSUESHigh-frequency live tissue welding (HF LTW), developed at tPWI in close cooperation with leading medical or-

ganizations of Ukraine, demonstrated its effectiveness and is successfully applied in surgical practice starting from 2002. During this time over 150 various surgical procedures have been mastered and more than 100 thou-sand surgical operations have been successfully performed in such fi elds as general and abdominal surgery, traumatology, pulmonology, proctology, urology, mammalogy, otolaryngology, gynecology, ophthalmology, etc. This method is highly promising also at transplantation of various organs.

HF LTW is believed to be particularly promising for application in veterinary medicine both for surgical treat-ment of animals (removal of tumors, castration, etc.), as well as for sanitization of cities.

Implants of hip joint with two-layer coating of titanium/hydroxyapatite

Implants of hip joint with porous titanium coating

Dental implants with coating of hydroxyapatite

Dental implant with porous titanium coating

All-purpose apparatus EKVZ-300 PATONMED© for live tissue welding


As confi rmed by numerous reports of leading surgeons and noted several times at various seminars and con-ferences, HF LTW method ensures:

■ bloodless, fast, convenient for the surgeon and low-traumatic for the patient performance of operative inter-vention, reliable hemostasis;

■ reduction of blood loss by almost 50%; ■ shortening of surgery duration by 20 - 50%; ■ high ablasticity of surgery performance; ■ absence of suppurations; ■ fast and complete postoperative rehabilitation; ■ possibility of surgical treatment of patients, who were regarded as inoperable.

Respective equipment and instruments create a practical basis for HF LTW process realization. Starting from the fi rst apparatuses created as far back as in the middle of the 1990s of the previous century, E.O.Paton Electric Welding Institute developed a whole range of apparatuses supporting such a process. The area of distribution of apparatuses of PWI design for HF LTW (about 150 apparatuses of various modifi cations) covers many regions of Ukraine, as well as such countries as the Russian Federation, Bulgaria and China.

EKVZ-300 apparatus offers wide possibilities for selection of operating algorithms and working parameters of the process, depending on the kinds of surgery and surgeon’s requirements. Adaptation, modifi cation and en-tering of additional programs are performed by user preference. It operates at frequencies of 66 and 440 Hz with power controlled in the broadest range practically from zero to maximum values of this parameter, equal to 300 W.

Software products and operating algorithms developed as a result of numerous comprehensive investigations conducted by PWI in close cooperation with Ukrainian medical specialists, ensure successful performance of sur-gery in the most diverse surgical fi elds, making EKVZ-300 apparatus to be a really unique and all-purpose tool in surgeon’s hands.

Instruments for HF welding in otolaryngology (a) and ophthalmology (b)

a b

Bipolar laparoscopic forceps (a), «spoon»-type probe (b) and fl exible endoscopic instrument (c)

a b c

250 210 200 180 160 150 140 165мм 290мм 270мм 210мм 210мм 160мм 160ммBipolar electrosurgical pincers and forceps

Bipolar instruments for HF live tissue welding


Equipment is, as a rule, fi tted with a basic set of tools (pincers and forceps). Customers are offered many types of instruments for open and laparoscopic surgery (see the reverse side of this brochure), including special instru-ments, for instance, for otolaryngology or ophthalmology. EKVZ-300 can operate with all the instruments for HF LTW developed at PWI so far. Adaptation and application of instruments from other manufacturers is also possi-ble. Simultaneous connection of two instruments by surgeon’s choice is envisaged.

THERMAL SURGERY EQUIPMENT FOR CONTACT FREE WELDINGOF LIVE TISSUES

The specialists of PWI participate for many years in the development of the innovative convection-radiation thermal surgery equipment for hemorrhages arrest, sanation of infected and chronic purulent wounds. The equip-ment combines the effect of hemostasis and sanation (elimination of microorganisms) during its effect on tissues. It is cost-effective in production and maintenance, has low power consumption (from 65 W), does not require gas-cylinder consumables (argon, nitrogen, compressed air), equipment and instruments are compact and light.

Capabilities: ■ hemorrhage arrest of parenchymatous organs (liver, spleen, pancreas, kidney), spongy bones and vessels of

up to 3 mm diameter; ■ sanation of infected and chronic purulent wounds; ■ contact free welding of tissues at overlapping of intestinal anastomoses and wounds of gastrointestinal tract; ■ tissues coagulation for bloodless incision; ■ data about ablastic effect (destruction of changed cells) are also available, as well as stimulation of reparation

processes (acceleration of wounds recovery without keloid cicatrices and commissural processes).PurposeCombination of hemorrhage arrest and wound sanation defi nes the wide capabilities of application in fi eld mili-

tary surgery, disaster medicine, in ambulance hospitals. The hemorrhage arrest in wound infected with microbes using the device under fi eld conditions allows preventing the behavior of infection process in the wound and con-siderably delaying the rendering of the qualifi ed medical aid. If necessary it allows conducting the operative inter-ventions at the facilities adapted to operation rooms where requirements to aseptics can not be performed.

The unique capabilities of equipment are widely used for rendering the specialized surgery aid, especially dur-ing operations on parenchymatous organs and this is in fact the only technology to conduct operations on pre-serving organs and functions during infectious pancreatitis.

Taking into account the wide range of purpose of the equipment, the corresponding series of equipment was worked out.

Advantages of contact-free high temperature treatment of live soft tissues: ■ reliable hemostasis; ■ possibility of formation of fi lms of coagulated blood at the surface of tissues; ■ no high temperature involvement of organ parenchyma; ■ possibility of safe work in the fi eld of large vessels and hollow organs in connection with absence of electric

current; ■ sterilization of infected and chronic purulent wounds; ■ simplicity of training and work as compared to most of electric surgery equipment (no need in special techni-

cal training of medical staff); ■ no need in consumables (gas).

Thermal coagulators

Thermal surgery instrument


TECHNICAL DIAGNOSTICS

AUTOMATED EXPERT SYSTEMS FOR TECHNICAL DIAGNOSTICSOF LOADED PARTS, FACILITIES AND STRUCTURES

The expert systems of series EMA-3 for technical diagnostics of loaded parts, facilities and structures applied in all industrial sectors are designed to perform the following operations:

■ control of diagnostic equipment; ■ automated measurement, collection, processing and storage of the diagnostic information in the on-line con-

trol or continuous monitoring mode; ■ determination of coordinates of the defects that are susceptible to propagation; ■ prediction of fracture loads at the initial stages of operation of a part, facility or structure; ■ calculation of residual life of a part, facility or structure, and setting of regulations for their possible further op-

eration.Expert technical diagnostic system EMA-3 provides a 100 % control and diagnostic of large-size parts, both

during operation and during testing without any preliminary preparation or disassembling. Also, EMA-3 is used for acoustic emission monitoring of probable initiation and propagation of cracks, which may form directly during the welding process in parts, facilities and structures under mass production conditions.

Basic system EMA-3BEquipment ■ measuring unit – 1 pc ■ unit of intermediate amplifi ers – 1 pc ■ acoustic emission sensors – 8-128 pcs ■ acoustic emission simulation sensor – 1 pc

Confi guration of computer for EMA-3Bbinuclear processor INTEL ■ RAM 2 GB ■ screen, not less than 1280x1024 ■ disk for not less than 300 GB ■ recording DVD drive ■ Windows XP – obligatory ■ Licence software ■ Microsoft Windows XP Professional ■ Microsoft Offi ce 2007 Professional package

EMA-3 package ■ program for acoustic emission tests ■ program for plotting of tables and test graphs ■ report master

User instructionExpanded system EMA-3RBasic system EMA-3B + software package with additional components: Mobile and stationary versions of

equipment EMA-3

Examples of parts (dehydrator, gas pipeline and chemical reactor) repaired by using expert technical diagnostic

system EMA-3

Adjustment of measurement and computation equipment of stationary diagnostic system EMA-3 for monitoring of

ammonia line across the Dnieper River


data base to store equipment settings, acoustic emission information and properties of materials ■ program for operation with data base ■ program for monitoring of mobile parts and assemblies of facilities ■ interactive help system ■ program for conversion of EMA-2 fi les into EMA-3 format

Versatile system EMA-3UExpanded system EMA-3R + software package with additional components:program for prediction of fracture load and danger warning ■ program for calculation of residual life ■ program for mathematical generation of test acoustic emission signals ■ program for conducting tests in continuous monitoring mode ■ interactive manual ■ program for conversion of EMA-2 fi les into EMA-3 format

Network system EMA-3SVersatile system EMA-3U + software package with additional components:program for network control of work stations (custom-made) ■ operation in local network with Internet access

Expert technical diagnostic system EMA-3 is designed for estimation of the state of pressure vessels, compres-sor stations, main pipelines, oil tankers, boilers and boiler plants, mobile parts and assemblies, including turbine rotors, facilities and structures applied in all industrial sectors during their operation and testing, prediction of frac-ture loads, calculation of residual life, and regulation of service conditions at the fi nal stage of operation.

Substantial extension of service life of parts, facilities and structures applied in all industrial sectors is provided through timely integrated estimation of their state and improved prediction of fracture loads as a basis of calcula-tion of the residual life. Continuous monitoring of parts, facilities and structures is mandatory at the fi nal stage of their operation. Expert system EMA-3 is a world leader in the corresponding fi eld.

Application of systems EMA-3 provides substantial saving of funds through prevention of losses caused by downtimes (routine maintenance, commissioning of equipment after repair, and other types of downtimes), elimi-nation of catastrophes and accidents. The payoff period is from 1 to 2 years.

The technical diagnostic systems have been applied in Ukraine, Russia and Poland for over 18 years. More than 1000 large industrial facilities in oil and gas industry, power engineering, pipeline transport and pressure vessels have been tested.

At present, the stationary EMA-3 based systems for continuous monitoring fi nd an increasingly wide applica-tion. Such systems are successfully used at the Odessa Port Plant and Ukrkhimtransammiak facilities.

MACHINE VISION SYSTEM FOR AUTOMATIC FOLLOWING OF THE BUTT IN ARC WELDING

Machine vision system (MVS) of triangulation type is contactless and features a high accuracy, informativity and reliability. It is capable of stable operation, also at welding arc running, providing all the necessary data for automatic following of the butt or the groove, as well as for monitoring weld reinforcement for its width, shape and cross-sectional area. MVS operates in real time, using the light section method (Fig. 1).

Triangulation type sensor (Fig. 2) consists of two main parts: videocamera and optical generator of the light band (lighter). Lighter positioned at a certain angle to the videocamera, projects a narrow band of light onto the surfaces being welded.

Parameters of the butt or the groove, which are determined and used to generate the control commands, in-clude: gap size in the butt of the edges being welded, value of edge misalignment in the mentioned butt, type of groove of edges being welded, and some other parameters of the butt or groove of edges being welded, allowing for the specifi c features of arc welding of certain items or metal structures.

Fig. 2. Triangulation type sensorFig. 1. Principle of operation of machine vision system of triangulation type.


The system provides butt joint parameters (gap, groove shape, groove depth, edge misalignment, etc.) in real time.

As regards automatic following of the butt or groove of edges being welded, a characteristic feature of machine vision system is its invariance to various types of noise such as solidifi ed molten metal drops, scratches, rust, scale, burrs, mill or cutter traces, glare, arc fl ashes, etc.

There are modifi cations of this sensory system for operation on surfaces with a high coeffi cient of refl ection, for instance, on scraped aluminium surfaces, as-milled steel surfaces, as well as with a capability of following an al-most zero gap.

Machine vision system promotes an essential improvement of welded joints quality in highly organized assem-bly-welding fabrication of metal structures:

■ in robotic engineering (Fig. 3, automatic welding of butt joints with a complex spatial trajectory); ■ in ship-building (hulls of ships and submarines, compartment partitions, etc.); ■ in fabrication of vessels, containers, and tanks (high pressure vessels, cases of containers and tanks, in-

cluding end plugs, intermediate containers for bulk cargo transportation, tank trucks, stainless steel tank-cars for food industry, gas storage tanks, refrigerator vans for cargo transportation, beer barrels, household hot water tanks);

■ in manufacture of railway carriages, tank-cars, tram and metro cars; ■ in automotive industry (3d structures of tailored blanks, briquettes for catalytic afterburners of exhaust gases,

exhaust systems, roof component, petrol tanks); ■ in assembling of heavy-duty vehicles and tractors (cabin assembly, wheels, crane beams, tractor

running gear); ■ in manufacture of large and small-diameter pipes (Fig. 4, oil and gas pipelines, chemical product pipelines,

household pipelines, fl exible pipelines, pipes for medical applications); ■ in fabrication of supports for powerful lighting systems in sports stadiums and in city streets.

Machine vision system can be used in all the arc welding processes, also in the presence of groove and trans-verse oscillations of the welding head. It is capable of following the trajectory of the butt with gaps close to zero, ensuring automatic alignment of welding head displacement trajectory and butt trajectory with 0.2 mm accuracy.

Fig. 3. Following system for robotic arc welding of curvilinear butt joints. Proceeding from the data

obtained from machine vision system the robotic system automatically generates a complex trajectory of welding

tool motion allowing for transportation lag.

Fig. 4. Application of machine vision system in pipe production (a – submerged-arc welding of large-diameter pipes; b – argon-

arc welding)

a

b


Adaptive control of the welding process is possible. If required by the customer, connection to welding equip-ment is performed through analog, digital or serial interfaces.

Improvement of effi ciency is achieved through saving of working time and expenses for assembly-welding op-erations and operations of monitoring weld reinforcement parameters, namely width, shape and cross-section-al area. Higher effi ciency is also promoted by prevention of irrepairable rejects and minimizing repair operations.

The system is a fi nished product and was introduced in mechanical engineering enterprises of Ukraine and Russia.

DIAGNOSTICS OF STRUCTURESUSING ELECTRON SHEAROGRAPHY METHOD

The electron shearography is the modern method of testing the structures allowing carrying out investigations in real time on the objects of intricate geometrical shape and optional dimensions.

The method is effi cient for application in industry in the following directions:

■ measuring and analysis of deformations; ■ non-destructive quality testing of structures, manu-

factured of different structural materials; ■ optimization of structure units and elements in the

process of their manufacture.The basic advantages of the method are as follows: in-

process quality testing; no contact; high sensitivity; pos-sibility to obtain information about deformation of surface of the test object; absence of requirements to protection against vibration and preliminary special preparation of test surface, automation of testing process.

The mobile shearography system is composed of the following components:

1 – small-size shearography interferometer;2 – laser with light guide;3 – portable computer.

DIAGNOSTICS OF STRESSED STATE OF STRUCTURES AND CONSTRUCTIONS BASED ON THE METHOD

OF ELECTRON SPECKLE-INTERFEROMETRYResidual stresses are known to be the cause for many accidents occurring in operation of facilities. Such acci-

dents involve considerable expenses for repair and reconditioning of the equipment, as well as potential hazard for human life and health.

The proposed technology improves the reliability and life of structures and constructions made from various structural materials. Instrumentation for on-line diagnostics of the stressed state and computer system of pro-cessing and analysis of the data obtained by the method of electron speckle-interferometry, operate in real time mode. The instrumentation is compact and allows determination of residual stresses under the actual service conditions for assessment of operational reliability of structures and constructions.

Equipment components: compact small-sized (17 mW) source of coherent laser radiation, polarized light guide designed for laser radiation transmis-sion into the controlled zone; controlled piezooptic element designed for achiev-ing a phase shift in processing of optical data; speckle-interferometer designed for strain measurement at stress relax-ation in the controlled zone; highly-sen-sitive CCD-camera designed for trans-mission of reflected laser radiation to computer memory; computer designed for entering, processing and analysis of optical data derived at strain measure-ment in the controlled section of the structure; and spare part kit. 1 – speckle-interferometer; 2 – light guide

3 – sample; 4 – laser with a power unit; 5 – computer


CENTRE FOR PHYSICAL-CHEMICAL INVESTIGATIONS OF MATERIALSThe Centre is equipped with a unique set of analytical and examination equipment produced by leading compa-

nies of Japan, USA and Western Europe, and is the only one of this type in Ukraine. The staff of the Centre con-sists of highly skilled specialists: 9 doctors and 16 candidates of sciences. Some of them worked on probation at research centers of the leading European countries and USA.

JEOL (Japan) JEM-200CX – transmission electron microscope which allows examination of structural and

phase composition of materials

Thermo Fisher Scientifi c (USA) ICP-spectrometer ICAP6500 DUO which allows analyzing the atomic chemical composition

of different materials

JEOL (Japan) scanning electron microscope JSM-840 with Link Systems (Great Britain) analysis system which is intended to investigate structure, surface topography,

character of fracture, microscopic chemical heterogeneity and element composition of metallic and non-metallic materials

BAIRD (The Netherlands) optical emission spectrometer SPECTROVAC-1000 DV-4 which allows analyzing the chemical composition of lump samples of iron-, nickel-, aluminium-, copper- and titanium-base alloys and pure

copper

LECO (USA) gas analysers RO-316 and RH-2 are intended for determination of contents of oxygen, nitrogen and

hydrogen in metals

Photoelectric vacuum spectrometer DFS-51U


Diffractometer DRON-3, UM-1 for X-ray phase analysis which is used for quantitative and qualitative examinations

of phase composition and structure of crystalline lattices and also different defects in them

CAMECA (France) microprobe CAMEBAX SX-50 for X-ray microanalysis

The Centre is active in the following areas: analytical examinations, materials stud-ies, physical-chemical investigations of pyrometallurgical processes, fundamen-tal research of physical and metallurgical processes of welding and related technol-ogies, and determination of causes and mechanisms of fracture of structures and welded joints.

RIBER (France) system LAS-2000 for surface examinations

DSI (USA) Gleeble-3800 automated dynamic system for modeling (simulation) of thermodeformation state of metals

JEOL Ltd. (Japan) Auger-microprobe JAMP-9500F with fi eld emission cathode completed with power dispersed spectrometer OXFORD EDS INCA Energy 350 for analysis of elements from beryllium to uranium.


COMPUTER PROGRAMS

CASPSP – SOFTWARE FOR COMPUTER SIMULATIONOF PLASMA SPRAYING PROCESS

CASPSP is a two-module package of applied programs for computer simulation of turbulent plasma jets, used at plasma deposition of coatings, as well as for simulation of the behaviour of spraying particles in such jets. The fi rst module is designed for simulation of turbulent plasma jets generated by plasmatrons with a smooth chan-nel and outfl owing into atmospheric pressure environment (APS). The respective computer program is based on mathematical model of gas dynamics and heat exchange in thermal arc plasma, described by a system of MHD-equations in the approximation of a turbulent boundary layer. This module allows calculation and representation of spatial distributions of temperature and velocity of the plasma jet allowing for electric arc processes running in the plasmatron, depending on the dimensions of its nozzle-anode, arc current, plasma gas type and fl ow rate.

Second module is designed for simulation of the behaviour of spraying particles in the plasma jet with pre-cal-culated distributions of temperature and velocity of plasma (approximation of low-particulate level jet). The re-spective computer program is based on the mathematical model of heating and acceleration of the spraying par-ticle, which is described by non-linear equation of heat-conductivity and equation of motion of a spherical particle in the plasma jet. This module allows calculation and representation of motion trajectory, velocity and tempera-ture fi eld of spraying particle depending on material and initial diameter of the particle, as well as conditions of its feeding into the plasma jet.

Used data bases:plasma gas: argon, nitrogen,particle material: Al – Cu – Mo – Ni – Ti – Al2O3 – Cr2O3 – Fe3C4 – TiO2 – ZrC2 – Cr3C2 – TiC – WC.Modifi cation (expansion) of the data bases is possible.

Applications.This software can be useful for specialists and stu-

dents dealing with plasma spraying.Technical and economic advantages. CASPSP al-

lows promptly and easily performing quantitative as-sessment of distributions of temperature and velocity in the plasma jet volume; trajectory, motion veloci-ty and thermal condition of the spraying particle de-pending on spraying process parameters. It lowers the costs for experiment performance and is faster than the modern FDM packages.

Effi ciency. 1 computation per 10 min of CPU.Requirements to computer. IBM PC or compatible:

AMD or Pentium (higher clock frequency is prefera-ble) with Windows 9x, ME, Windows NT/2000/XP op-erational system. RAM: minimum 16 MB (prefera-bly 32 MB). HDD free space: minimum 4 MB, FDD: 1.44 MB, 3.5″. Monitor: SVGA, 65536 colours, 1024 by 768 dots.

COMPUTER PROGRAM«WELDING OF MULTI-PASS CIRCUMFERENTIAL WELD»

The software «Welding of multi-pass circumferential weld»makes it possible to predict the residual stresses and strains in the zone of butt weld of the thick-walled shell in multi-pass welding (non-symmetric case) with ac-

count for phase transformations, different parameters of edge preparation, welding conditions and conditions of fi xture (Figure 1).

The thick-walled shells, welded by the multi-pass fusion welding, are a rather typical structure. By varying the geometric sizes, rigidity of frame ring, properties of materials of shells and also coordinates of characteristic points of edge preparation, it is possible to describe many cases of welding of real structures of this type. The residual welding stresses, and also strains in the zone of butt of these structures represent interest to specialists for a long time, as the level of residual stresses defi nes the serviceability of these joints at alternating loads (multi-cyclic fatigue, and also resistance to different cor-rosion damages of the internal surface, if the structure is used for transpor-tation or storage of appropriate aggressive media. In its turn, the welding strains, connected with rather large radial displacements of shells wall in the butt zone, can create certain service complications, and the axial displace-

Fig.1. Macrosection of welded joint of steel 17GS (δ=16 mm) made by

multi-pass arc welding with electrodes UONI-13/55


ments in the groove zone, connected with a transverse shrinkage, can change noticeably the groove width in multi-pass welding, that creates the certain technological diffi culties in automatic welding and so on.

It is diffi cult to model the mentioned phenomena on specimens, and the use of full-scale experiments at large sizes of the structure for opti-mizing the technology are connected with high time and material expens-es that predetermines the increased interest to mathematical modeling of these phenomena. However, here the actual is the question of acces-sibility of application of this approach for user, having a limiting access to packages of commercial computer programs of SYSWELD, ABAQUS, ANSYS, MARC and other types, characterized by a rather large exces-siveness, as applied to this task and, naturally, high rental cost.

To solve this problem, the present software «Welding of multi-pass cir-cumferential weld», oriented to engineering application and not requiring the special training of the user in the fi eld of methods of calculation was developed.

To select the parent metal, and also a fi ller metal separately for the root, main and fi nishing passes, a built-in databank is provided, including all necessary information for calculation by properties of materials, and which can be added by the user. In entry of general geometric parame-ters (Figure 2) the shell parts being welded should have a similar internal diameter D, but can differ in thickness of wall H1 and H2 , length L1and L2, the presence and arrangement of ring frames S1 and S2. Figure 3 gives some examples of thick-walled shells, welded by the multi-pass fu-sion welding.

It is also necessary to enter the data of welding conditions for each type of welding pass, and also to preset the geometry of a groove for edges of shells being welded. Basing on this information, the program defi nes auto-matically the required number and layout of welding passes. Here, it is pos-sible to control the groove fi lling almost in the real-time condition.

During calculations a two-dimensional model (non-symmetric case) is used, based on hypothesis of a plane deformation, method of thermoplastic-ity and fi nite element method. Temperature and mechanical tasks for each welding pass are given successively with time from the beginning of heat-ing up to full cooling of the metal. The calculation model takes into account the dependence of physical mechanical properties of materials on tempera-ture, and also microstructural phase transformations. The sizes and shape of the zone of penetration of the parent material and previous layer (in two-layer welding) are determined. Basing on these data, the average chemical composition of melting zone (MZ) is evaluated, that is a basis for the further calculation of its microstructural state. The microstructural state of MZ and HAZ are calculated using the Shaeffl er’s diagrams for the high-alloy steel, or using the appropriate diagrams CCT for low-alloy ferrite steels. The appro-priate characteristics for parametric equations, relating the amount of an ex-pected phase in microstructure with time of cooling t8/5 within 800 – 500 °C interval, are available in the databank. The knowledge of temperature fi elds and volume changes, connected with temperature expansion and micro-structural changes, allows observe the developing of elastic-plastic deforma-tions up to fi nal state.

Thus, the result of calculation is the following information: ■ zone of penetration (chemical composition and layout of welding passes); ■ time of cooling t8/5 within 800 – 500 ºC in MZ and HAZ;

Fig.2. View of main window of data input

Fig.3.Examples of thick-walled shells, welded by multi-pass butt weld:

a – simple shells;b – shells with different thickness;c – shells with internal frame rings

Fig.4. Zone of penetration Fig.5. Time of cooling t8/5 within800 – 500 ºC in MZ and HAZ

Fig.6. Relative content of martensite in MZ and HAZ


■ microstructural phase composi-tion (relative content of martensite, austenite, bainite and ferrite-pearl-ite in MZ and HAZ);

■ residual stresses (axial, circum-ference, radial and tangent compo-nents);

■ deformations (radial bending and axial shortening);

■ mechanical properties (hardness by Vickers, ultimate strength,, yield strength, elongation, reduction in area, impact strength in MZ and HAZ).In case of use of materials without

microstructural transformations the results Nos. 2,3 and 6 are not determined. Some examples of graphical rep-resentation of results of calculation can be presented in the form of tables of values. The program has the possi-bility of selection of support of interface and references in two languages (Russian and English).

There is a demonstration version in two languages (Russian and English).Field of applicationManufacture of welded thick-walled cylindrical shells.Technical-economic advantagesSpecialized program has the following advantages: ■ reduction in labor consumption owing to simple interface of data input and full automation of processes of

creation of a mathematical model, division of region into fi nal-element grid, searching for solution and visualiza-tion of results;

■ elimination of attending personnel, because engineer-welder or technologist can operate with program, but not a specialist on numerical methods of solution of mathematical problems;

■ cost of program for continuous use is 5-20 times lower than the cost of license per 1 year for commercial general-purpose program packages.

■ Effi ciency. Time of calculation with account for data input of approximately 10 – 60 min depends on select-ed materials and geometric parameters of welded joint, number of welding passes (it is better than analogs be-cause of time saving for data input, creation of model and visualization of results).

MATERIALS

UNDERWATER WELDING AND CUTTING OF METALSAt PWI the technology, welding consumables and equipment for welding

and cutting of metals under water have been developed.The fi eld of application: repair of underwater metal structures, pipelines,

fl oating ships and port engineering constructions.

Fig.7. Radial bending of shellFig.8. Circumference component of

residual stressesFig.9. Axial component of residual

stresses

Fig.10. Impact strength in MZand HAZ

Fig.11. Vicker’s hardness in MZand HAZ


FLUX-CORED WIRE PPS-AN2This wire is designed for the underwater semiautomatic weld-

ing of low-carbon and low-alloy steels with carbon equivalent of up to 0.35 and yield strength of up to 350 MPa at depths of up to 30m. It is manufactured of 1.6…1.8 mm diameter. Welding is performed using a specialized semiautomatic machine. To sup-ply the arc, the welding power sources with a rigid external volt-ampere characteristic, increased open-circuit voltage and 500 A maximum current are used.

The mechanical properties of weld metal are obtained of not lower than:

■ tensile strength – 430 MPa; ■ elongation – 12 %.

ELECTRODES EPS-AN1These electrodes are designed for underwater wet welding of low-carbon and low-alloy steels with carbon

equivalent of up to 0.35 and yield strength of up to 350 MPa. They are manufactured of 3 to 5 mm diameter. Welding is performed using a special electrode holder of DPS-AN1 type. To supply the arc, the welding power sources with a falling external volt-ampere characteristic, increased open-circuit voltage (≥60 V) and maximum current of not lower than 300 A are used.

The mechanical properties of weld metal are obtained of not lower than:

■ tensile strength – 420 MPa; ■ elongation – 12 %.

Welding is used in construction and repair of port engineering constructions, repair of fl oating ships, restoration of different-pur-pose underwater pipelines, construction and repair of water sup-ply systems, in emergency-rescue operations etc.

FLUX-CORED WIRE PPR-AN3This wire is designed for underwater semiautomatic oxygen-free cutting of low-alloy and stainless steels of up

to 40mm thickness, aluminium, titanium and their alloys of up to 20 mm thickness at up to 60 m depths. It is man-ufactured of 2.0-3.0 mm diameter. The effi ciency of cutting is 15-20 m/h on 10–15 mm thick steel sheet. In alu-minium cutting the speed is 1.5-2.0 times increased, while in copper cutting it is 2-3 times decreased.

ELECTRODES ANR-T8These electrodes are designed for oxy-electric cutting of low-

carbon and low-alloy steels of up to 40mm thickness at up to 60m depths. They are manufactured of 8mm diameter. Cutting is per-formed using a special electrode holder of EKD-AN3 type. To supply the arc, the welding power sources with a falling external volt-ampere characteristic, increased open-circuit voltage (≥60 V) and maximum current of not lower than 300A are used.

They provide the cut length by one electrode of not less than 250 mm on 20 mm thick steel sheet, 300 - 350 mm on 14 mm thick sheet and cutting speed of not less than 12m/h. Time of one electrode operation is ~1.5min, electrode weight is ~180 g. Oxy-gen consumption is 0.2 - 0.25 m3/m.

Appearance of the cut performed at 30m depth


ELECTRODES ANR-5PThese electrodes are designed for underwater arc cutting of up to 14 mm thick steels. They are manufactured

of 4 to 5 mm diameter. The cutting is performed using a special electrode holder of DPS-AN1 type. To supply the arc, the power sources with a falling external volt-ampere characteristic, increased open-circuit voltage (≥60 V) and maximum current of not lower than 300 A are used.

The cut length of 14mm thick metal is 100 mm using one electrode.Cutting is used in dismantling of underwater piles of stationary platforms, for cleaning the water areas from

sunken ships, repair of pipelines, sheet pilings, ship raising and emergency-rescue operations.

TECHNOLOGY OF BRAZINGAt PWI the brazing alloys and high-effi cient equipment for high-temperature brazing of critical structures of dis-

similar materials have been developed.

Brazed model of diverter unit of thermonuclear synthesis installation (copper-tungsten joint)

Bit with diamond- hard alloy cutters for underground drilling.

High-effective rocket lattice rudders, manufactured by brazing in rotary vacuum furnace

The brazed joints of copper-tungsten pos-sess a good serviceability, including that un-der the effect of neutron irradiation and se-vere thermal cycling.

Technology of manufacture and repair of drilling bits with diamond- hard alloy cutters was developed for pro-duction of dissipated mine methane, which allowed in-creasing the mean value of digging up to 1000-1500 m.

Technology of high-temperature brazing allowed manufacturing thin-walled lattice structures used in sys-tems of vehicles control.


PENETRATION ENHANCING AEROSOL ACTIVATOR

Penetration enhancing aerosol activator (PATIG) for tungsten in-ert gas arc welding (TIG) of steel structures:

■ 2-4 time increase of penetration depth; ■ elimination or reduction of change of penetration depending on

chemical composition of steel; ■ removal of pores; ■ reduction of welding deformations and shrinkages.

PATIG activator is simply sprayed over the surface of edges to be welded before performance of common TIG.

Application of PATIG activator is effi cient for TIG welding in ar-gon, helium as well as their mixtures.

It can be used for: ■ one-sided single-run TIG welding of thicknesses up to 12 mm

without edge preparation and fi ller wire of simple steels as well as steels with limited weldability;

■ repair of different defect (pores, cracks and etc.) by means of remelting of material at up to 14 mm depth without machining and repeated fi ll;

■ 2–7 time increase of welding effi ciency as well as 3-6 time re-duction of fi nancial and labor expenses are provided.

Main areas of application: ■ heat and nuclear-power engineering; ■ chemical, petrochemical and power machine building; ■ aerospace industry; ■ shipbuilding; ■ pipeline armature engineering; ■ pipeline construction.

PATIG aerosol activators are delivered in cans of different capac-ity from 80 up to 210 cm3 for welding of not less than from 10 to 20 running meters of weld, respectively.

Tested by world well-known welding centers:The Welding Institute (TWI), Great Britain;Institut de soudure (IS), France;Institute of welding and quality (ISQ), Portuguese;Welding Technology Institute of Australia.

activator

a b


«Sovremennaya Elektrometallurgiya»(Electrometallurgy Today)The subjects of the journal are devoted to the theory and experience of application

of electroslag, electron beam and plasma arc technologies, vacuum-arc remelting and induction melting. The articles include the theory and practice of ladle steel treatment using power and resource saving metallurgy technologies and general matters of met-allurgy. Published in Russian since 1985, four issues per year.

«Tekhnicheskaya Diagnostika i Nerazrushayushchiy Kontrol» (Technical Diag-nostics and Nondestructive Testing)

The journal presents articles on problems of NDT and diagnostics of metal struc-tures, evaluation of state and prediction of residual life of products and constructions, modifi cation of methods of technical testing to improve quality of industrial products, reliability and longevity of critical objects, results of investigations, developments and application of modern methods of diagnostics and NDT, reviews and other scientif-ic and technical information. Published in Russian and Ukrainian since 1989, four is-sues per year.

«Avtomaticheskaya Svarka» (Automatic Welding)The journal publishes a wide range of information refl ecting results of scientifi c and

experimental research works carried out in the fi eld of welding and related technolo-gies, and also information about technologies, equipment and materials for welding, cutting, brazing, surfacing and deposition of protective coatings. Published in Russian since 1948, twelve issues per year.

«The Paton Welding Journal»English translation of the journal «Avtomaticheskaya Svarka». Published since

2000, twelve issues per year.

«Svarshchik» (Welder)The journal is intended for specialists of enterprises and organizations of all types of

property (engineers, technologists, servicemen and welders), involved in the produc-tion of welded structures, welding consumables and equipment: specialists in stan-dardization and certifi cation, labor and environment protection, lecturers of techni-cal colleges and training centers, managers of commercial companies working at the welding market.www.welder.kiev.ua

JOURNALS, PUBLISHED BY PWIwww.patonpublishinghouse.com

Contents

TECHNOLOGIES AND EQUIPMENT

High-speed electroslag welding of thick-plate metal without normalization of welded joints ............................. 3

Technology and equipment for electroslag welding of busbars of aluminium electrolysers under conditions of service and powerful magnetic fields .................................................................................3

Technology and equipment for electroslag casting of shaped high-strength steel billets .................................. 4

Electric arc consumable nozzle welding ............................................................................................................5

Machines for flash-butt welding of unmeasured rolled metal ................................................................................6

Technology and equipment for automatic continuous flash butt welding of pipelines .......................................8

Innovative technologies and equipment for pulsed flash butt welding of rails of modern production.........................................................................................................................................8

Technology and equipment for flash butt welding of rail frogs using pulsed flashing ...................................... 10

Technology and equipment for flash butt welding of cutting tools ...................................................................10

Technology and equipment for MIAB welding of parts of hollow and solid section ......................................... 11

Flash-butt welding of products of alloys based on aluminium, magnesium, titanium, stainless and heat-resistant steels and alloys .............................................................. 11

Technology and equipment for flash butt welding of bar reinforcement ..........................................................12

Pulse technologies for hardening of tools and parts of machines ...................................................................13

Cumulative-detonation technology for depostion of coating ................................................................................13

Plasma metalization of axles of railroad transport ...........................................................................................14

Plasma powder cladding of power, chemical and general engineering parts .........................................................................................................................14

Equipment and technology of microplasma spraying of coatings ...................................................................15

Welding restoration of all-cast assemblies and parts of industrial equipment ................................................. 16

Technology for recovery of carrying capacity of different-purpose pipelines and welding of branch pipes to them under service conditions ...........................................................................................16

Technologies of repair-restoration works of bridge metal structures ...............................................................17

Technology for welding of tubular structures ...................................................................................................18

Welding, cutting and explosion treatment ........................................................................................................18

Structures of transformable volume (STV) ......................................................................................................19

Equipment for electron beam welding ............................................................................................................20

Microplasma spraying of biomedical coatings .................................................................................................23

High-frequency electric welding of soft live tissues .........................................................................................23

Thermal surgery equipment for contact free welding of live tissues ................................................................25

TECHNICAL DIAGNOSTICS

Automated expert systems for technical diagnostics of loaded parts, facilities and structures ....................... 26

Machine vision system for automatic following of the butt in arc welding........................................................27

Diagnostics of structures using electron shearography method ......................................................................29

Diagnostics of stressed state of structures and constructions based on the method of electron speckle-interferometry ...................................................................................................................29

CENTRE FOR PHYSICAL-CHEMICAL INVESTIGATIONS OF MATERIALS ................................................. 30

COMPUTER PROGRAMS

CASPSP – software for computer simulation of plasma spraying process .............................................................................................................................32

Computer program «Welding of multi-pass circumferential weld» .................................................................................................32

MATERIALS

UNDERWATER WELDING AND CUTTING OF METALS ...............................................................................34

Flux-cored wire PPS-AN2................................................................................................................................35

Electrodes EPS-AN1 .......................................................................................................................................35

Flux-cored wire PPR-AN3 ...............................................................................................................................35

Electrodes ANR-T8 ..........................................................................................................................................35

Electrodes ANR-5P ..........................................................................................................................................36

TECHNOLOGY OF BRAZING ........................................................................................................................36

PENETRATION ENHANCING AEROSOL ACTIVATOR ..................................................................................37

JOURNALS, PUBLISHED BY PWI .................................................................................................................38

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