(ew609) -pocket welding guidsse - a guide to better welding-hobart institute of welding technology...

7/26/2019 (EW609) -Pocket Welding Guidsse - A Guide to Better Welding-Hobart Institute of Welding Technology [Yasser Taw

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Pocket Welding GuideA Guide to Better Welding

30th Edition RevisedAll Rights Reserved

including the right to reproduce this book orportions thereof in any form

byHobart Institute of Welding Technology

400 Trade Square East Troy, OH 45373 USA

Filler metal information courtesyHobart Brothers Company, Troy, Ohio, USA.

State Board of Career Colleges and SchoolsRegistration No. 70-12-0064HT

Accrediting Commision of Career Schools

and Colleges of Technology No. 000403

2010 Hobart Institute of Welding Technology

ISBN: 978-1-936058-28-0

Cover photo: Hobart Institute Instructor Luke Bailey welding pipe.

EW609

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INTRODUCTION

The Pocket Welding Guide began as a 30-page bookletwith 3.5 x 5.5-inch dimensions that would actually tinto a shirt pocket. In fact, the early title of the bookwas Hobart Vest Pocket Guide to Better Welding.

The booklet contained three types of electrodes, fouressentials of proper welding procedures, types of jointsand welding positions, early welding symbols, some ofthe early build your own Hobart welding generators,and a page of the early Practical Arc Welding trainingbooks.

The up-to-date welding training was, at that time,

being provided at the Hobart Trade School. It is statedon the cover, Thousands of men and women havereceived thorough training at the Hobart Trade School,and have immediately stepped into high paying jobs.

It goes on to indicate that the training was beingoffered to those interested in preparing for steadyemployment in post-war industry. And that trainingwas fully accredited under the G.I. Bill.

With each new edition, more information was added.More welding symbols were developed, welding termshave been standardized and added and today, in its30 th edition, the book is 146 pages in length. It hasbeen completely revised and improved. The Pocket

Welding Guide is a great addition to any welderstoolbox. It remains a quick and ready reference.

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FOREWORD

This 30 th edition of the Pocket Welding Guide isdedicated to all those who are interested in and workwith any aspect of welding. It covers a wide varietyof subjects that are essential for the student orbeginner and are of interest to the veteran welders,draftsmen, instructors, supervisors, foremen,technicians, and engineers.

You are encouraged to strive for the perfect weld.Putting every effort forth to attain it will make youmore valuable as a welder. No matter what yourtask may be, you can do no better than to try forperfection.

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ContentsWelding & Cutting Processes ..........................................................................65 Essentials for Good Welding .....................................................................16Examples of Good & Bad Beads ..................................................................18Common Welding Problems, Causes and Cures ................................... 30Checkpoints for Quality Welding ...............................................................33Welding Positions ............................................................................................35 Types of Joints ...................................................................................................37

Welding Symbols .............................................................................................38General Welding Safety .................................................................................44Welding Metals .................................................................................................48Steel Available for Welding...........................................................................49Identification of Metals ..................................................................................50 Typical Preheating for Various Metals ......................................................52AISI-SAE Designation System for

Carbon and Alloy Steels ............................................................................53Cost Saving Hints .............................................................................................548 Factors to Consider When Selecting Electrodes................................ 56Metal Cored Wire ..............................................................................................57Oven Storage & Reconditioning of Filler Metals ................................... 59How To Calculate Filler Metal Consumption ..........................................60Shielding Gases & Their Uses .......................................................................62AWS Electrode Classifications & Comparative Indices........................ 63

GMAW Short Circuiting Transfer WeldingParameters & Shielding Gases ...............................................................74 GMAW Spray Transfer Welding Parameters

& Shielding Gases ......................................................................................75Hobart Filler Metals .........................................................................................79 Mild & Low Alloy Steel Electrodes ........................................................79 Stainless Steel Electrodes ........................................................................92 Mild Steel Solid Wires ...............................................................................95

Tubular Wires ...............................................................................................99 Metal Cored Wires ....................................................................................109 Hard Surfacing ..........................................................................................113

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Filler Guide for Welding Aluminum .........................................................114Filler Metal Selector Guide for Welding ASTM Steels ........................ 115Welding Terms & Definitions......................................................................136Metric Conversion Tables ............................................................................140HIWT Training & Certification Services ...................................................143HIWT Training Materials...............................................................................144Index ...................................................................................................................145

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Welding & Cutting Processes

SMAWShielded Metal Arc Welding, also called Stick welding and Manual Metalwelding is an electric arc welding process that produces coalescence ofmetals by heating them with an arc between a covered consumable metalelectrode and the work. Shielding is obtained from decomposition ofthe electrode covering. The process is normally manually applied and iscapable of welding thin and thick steels and some nonferrous metals in allpositions. The process requires a relatively high degree of welder skill.

GMAWGas Metal Arc Welding, also known as MIG welding, CO 2 Welding,Micro Wire Welding, short arc welding, dip transfer welding, wire weld-ing, etc., is an electric arc welding process that produces coalescenceof metals by heating them with an arc between a solid, continuous,consumable electrode and the work. Shielding is obtained from anexternally supplied gas or gas mixture. The process is normally appliedsemiautomatically; however, the process may be operated automaticallyand can be machine operated. The process can be used to weld thin andfairly thick steels and some nonferrous metals in all positions. A relativelylow degree of welding skill is required for the process.

FCAWFlux Cored Arc Welding, also known as Dual-Shielded, Inner-shield, SelfShield, FabCO, etc., is an electric arc welding process that produces co-alescence of metals by heating them with an arc between a continuousflux filled electrode wire and the work. Shielding is obtained throughdecomposition of the flux within the tubular wire. Additional shield-ing may or may not be obtained from an externally supplied gas or gasmixture. The process is normally applied semi-automatically, but canbe applied automatically or by machine. It is commonly used to weldmedium to thick steels using large diameter electrodes in the flat and hori-zontal position and small electrode diameters in all positions. The processis used to a lesser degree for welding stainless steel and for overlay work. The skill level required for FCAW is similar to GMAW.

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Protective Gas FromElectrode Coating

Molten WeldMetalSlag

SolidiedWeld Metal

Electrode Wire

Base Metal

SolidiedWeld Metal

Molten Weld Metal

Shielding Gas Nozzle

Electrode

ArcBase Metal

Gas (Optional)Molten Metal

MoltenSlag

SolidiedWeld Metal

Nozzle (Optional)

SlagFlux CoredElectrode

Arc

Base Metal

Arc

Metal Droplets

Electrode Coating

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SAWSubmerged Arc Welding, also known as Union Melt, Hidden Arc, WeldingUnder Powder, etc., is an arc welding process that produces coalescenceof metals by heating them with an arc or arcs between a bare electrode orelectrodes and the work. The arc is shielded by a blanket of granular fluxon the work. The process is normally applied by machine or automatically,but is used on a limited basis semi-automatically. It is used to weld mediumto thick steel in the flat and horizontal position only. Manual welding skillis not required; however, a technical understanding of the equipment andwelding procedures is necessary to operate the process.

GTAWGas Tungsten Arc Welding, also known as TIG welding, Heliarc Welding,Heli-Welding, Argon-Arc Welding and Tungsten Arc Welding, is an electricarc welding process that produces coalescence of metals by heating themwith an arc between a nonconsumable tungsten electrode and the work.Filler may or may not be used. Shielding is obtained from an inert gas or aninert gas mixture. The process is normally applied manually and is capableof welding steels and nonferrous metals in all positions. The process is com-monly used on thin metals and for the root and hot pass on tubing and pipe.Requires a relatively high degree of welder skill.

PAWPlasma Arc Welding, sometimes referred to as Needle Arc and Micro Plasma, isan electric arc welding process that produces coalescence of metals by heat-ing them with a constricted arc between a tungsten electrode and the work(transferred arc) or the electrode and the constricting nozzle (non-transferredarc). Shielding is obtained from the hot ionized gas issuing from the orifice.An auxiliary inert shielding gas or mixture of inert gases may supplement the

system. The process is commonly applied manually, but may be automaticto increase welding speeds. It can be used to weld almost all metals andcan be all position at lower currents. Normally used on thinner metals, theprocess requires a slightly lesser degree of welder skill than Gas TungstenArc Welding, but a greater knowledge of equipment set-up.

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Electorde

Base MetalArc PathMoltenWeld Metal

Shielding Gas

Molten WeldMetal

SolidiedWeld Metal

Base Metal

Welding Torch

Tungsten Electrode

Arc

Filler Rod

Orice to Constrict Arc

Plasma Stream

Shielding GasSolidiedMetal

Molten Weld Metal

Base Metal

Filler Metal

TungstenElectrode

Coolant

Slag Molten FluxFrom Flux

Hopper

Flux Blanket

SolidiedWeld Metal

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CAWCarbon Arc Welding, is an electric arc welding process that produces acoalescence of metals by heating with an arc between a carbon electrodeand the work. No shielding is used. A variation of the process uses twocarbon electrodes with an arc between them. The process is normally ap-plied manually and is capable of welding thin metals. The process is alsocommonly used for brazing. It requires a relatively high degree of weldingskill. This process has limited industrial popularity.

ESWElectroslag Welding, also known as Porta-Slag or Slag Welding, is a weldingprocess that produces a coalescence of metals with molten slag which meltsthe filler metal and the surface of the work to be welded. The molten weldpool is shielded by a slag covering which moves along the joint as weldingprogresses. The process is not an arc welding process, except that an arc isused to start the process. After stabilization the molten slag provides thenecessary heat for welding. The process is always applied automatically. It isa limited application process used only for making vertical welds on mediumto heavy thickness of mild steel. Manual welding skill is not required, but atechincal knowledge of the process is required to operate the equipment.

EGWElectrogas Welding, also known as Verti-Matic and Automatic Vertical Airco-matic, is an arc welding process that produces a coalescence of metals byheating them with an arc between a continuous filler metal (consumable)electrode and the work. Molding shoes are used to confine the moltenweld metal for vertical position welding. The electrode may be either fluxcored or solid. Shielding may or may not be obtained from an externallysupplied gas or gas mixture. The process is always applied automatically. It isa limited application process used only for making vertical welds on medium

to heavy thickness mild steel. Manual welding skills are not required, butlike electroslag welding, a technical knowledge of the process is requiredto operate the equipment.

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Base MetalFiller Rod

Arc Stream Arc FlameElectrode

Arc Core

Base Metal

Electrode

Consumable Guide Tube

Base Metal

Molten Flux

Molten Weld Metal

Solidied Weld Metal

Shielding Gas

Shielding Gas

Electrode Conduit

Welding Head

Water Out

Water In

Solidied Weld Metal

Water In

Water Out

Shielding Gas

Molten Weld Metal

Electrode Wire(Tubular or Solid)

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SWStud Welding, also known as Arc Stud Welding, is a special purpose arc weld-ing process used to attach studs to base metal. Partial shielding is obtainedby a ceramic ferrule surrounding the stud. It is a machine welding process,using a specialized gun that holds the stud and makes the weld. The processis normally used on steels in the flat and horizontal position. A low degreeof welding skill is required for stud welding operation.

OAWOxyacetylene Welding, sometimes referred to as Gas Welding, Oxy-Fuel GasWelding, and Torch Welding, is an oxy-fuel gas process that produces a coales-cence of metals by heating them with a gas flame or flames obtained fromthe combustion of acetylene with oxygen. The process may be used withor without filler metal. It can be used on thin to medium thickness metalsof many types, steels and nonferrous in all positions. The process is appliedmanually and requires a relatively high degree of welding skill.

TB Torch Brazing, sometimes called Gas Brazing, is similar to OxyacetyleneWelding, except the base metal is not melted, and the filler metal is usually anonferrous metal. The filler metal flows into the joint by capillary attraction.Brazing can be done in all positions on most metals and is especially popularfor repair work on case iron. The process is normally applied manually and

requires a relatively high degree of brazer skill.

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Welding Torch Tip

Acetylene Feather

Molten Weld Metal

SolidiedWeld Metal

Base Metal

Inner Cone

Filler Rod

DepositedBraze Metal

Base Metal Inner Cone

BrazingFiller Metal

Acetylene Feather

Welding Torch Tip

A B C D

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OCOxygen Cutting, also known as Oxygen Fuel Gas Cutting, Acetylene Cut-ting, Gas Cutting and Burning, is a thermal process used to sever metals byheating the metal with a flame to an elevated temperature and using pureoxygen to oxidize the metal and produce the cut. Different fuel gases canbe used including: acetylene, natural gas, propane and various trade-namegases. The process is normally applied manually with hand-held torchesor by machine with highly accurate tracing devices and multi-torches forcutting simultaneous shapes. It is used to cut thin to very thick metals,primarily steels; however, with various arrangements it can be used onother metals. Manual oxygen cutting requires a fairly high degree offlamecutter skill.

PACPlasma Arc Cutting, sometimes called Plasma Burning and Plasma Machin-ing, is an arc cutting process which severs metal by melting a localizedarea with a constricted arc and removing the molten material with a highvelocity jet of hot ionized gas issuing from the orifice. It can be used witha hand held torch manually or by machine cutting in extremely accuratemachines with special tracing devices. It is used for cutting steels and nonferrous metals in thin to medium thicknesses. The process requires a lesserdegree of cutter skill than oxygen cutting except the equipment is muchmore complex for manual operation.

AACAir Carbon Arc Cutting and Gouging is a process in which metals to be cutare melted by the heat of a carbon arc and the molten metal is removed bya blast of air. Normally, it is a manual operation used in all positions, but

may also be operated automatically. The process can be used on steels andsome nonferrous metals. The process is commonly used for back gougingwelds, for gouging out defective welds and repairing castings. The processrequires a relatively high degree of cutting skills.

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Slag

Base Metal

Preheat Flames

Cutting Tip

Oxygen Jet

Plenum Chamber

Orice GasNozzle

Shielding Gas

Shielding Water

Base Metal

Tungsten Electrode

Shielding WaterNozzle

Outer Gas Cup

Constricting OriceArc

Hand Held Electrode Holder

Carbon ElectrodeAir Stream

Work Lead

Base Metal

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5 Essentials forGood Welding

1. Correct Electrode Size2. Correct Current3. Correct Arc Length4. Correct Travel Speed5. Correct Electrode Angle

Besides the steady sizzling sound that a correct arc produces,the shape of the molten pool and the movement of the metalat the rear of the pool serve as a guide in checking weld qual-ity. In a correctly made deposit the ripples produced on thebead will be uniform and the bead will be smooth, with no

overlap or undercut.1. Correct Electrode Size

The correct choice of electrode size involves considerationof a variety of factors, such as the type, position, andpreparation of the joint, the ability of the electrode to carryhigh current values without injury to the weld metal orloss of deposition efficiency, the mass of work metal andits ability to maintain its original properties after welding,

the characteristics of the assembly with reference to effectof stresses set up by heat application, the practicability ofheat treatment before and/or after welding, the specicrequirements as to welding quality and the cost of achiev-ing the desired results.

2. Correct CurrentIf current on equipment is too high or too low, you arecertain to be disappointed in your weld. If too high, theelectrode melts too fast and your molten pool is large andirregular. If too low, there is not enough heat to melt thebase metal and your molten pool will be too small, willpile up, look irregular.

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3. Correct Arc LengthIf the arc is too long or voltage too high the metal meltsoff the electrode in large globules which wobble fromside to side as the arc wavers, giving a wide, spatteredand irregular bead with poor fusion between originalmetal and deposited metal. If the arc is too short, or volt-age too low, there is not enough heat to melt the basemetal properly and the electrode quite often sticks to thework, giving a high, uneven bead, having irregular rippleswith poor fusion.

4. Correct Travel SpeedWhen your speed is too fast your pool does not last longenough, impurities and gas are locked in. The bead isnarrow and ripples pointed. When speed is too slow themetal piles up, the bead is high and wide, with a ratherstraight ripple.

5. Correct Electrode Angle The electrode angle is of particular importance in lletwelding and deep groove welding. Generally speaking,when making a llet weld, the electrode should be held sothat it bisects the angle between the plates (as shown atright) and is perpendicular to the line of weld. If undercutoccurs in the vertical member, lower the angle of the arcand direct the arc toward the vertical member.

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Examples of Good and Bad Beads

GoodProper Current

Voltage & Speed

Cross-section Weld Bead

Weld Bead FaceSMAW 7018

A smooth, regular,well-formed weld bead.

No undercut, over-lap orpile up

Uniform in cross-section.

Excellent weld atminimum material

and labor cost.

BadWelding Current

Too Low

BadWelding Current

Too High

Cross-section Weld Bead Cross-section Weld Bead


Excessive piling up ofweld metal.

Slow up progress.

Wasted ller metaland time.


Excessive spatterto be cleaned off.

Undercutting alongedges weakens joint.

Irregular deposit.


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Shielded metal arc weldingAWS E7018 - General Purpose Electrode

BadArc Too Long

(Voltage Too High)

BadWelding Speed

Too Fast

BadWelding Speed

Too Slow

Cross-section Weld Bead Cross-section Weld Bead Cross-section Weld Bead


Weld bead very irregularwith poor penetration.

Weld metal notproperly shielded.

An inefficient weld.



Weld bead too small, withirregular contour.

Not enough weldmetal in the cross-section.

Weld not strongenough.



Excessive piling upof weld metal. .

Too much timeconsumed.

Wasted electrodesand productive time.

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GoodProper CurrentVoltage & Travel

Weld Bead Face

SMAW 6010

Smooth, regular,well formed bead.

No undercut, over-lap orpile up.



and labor cost.


BadWelding Current

Amp Too Low

Weld Bead Face

SMAW 6010

Excessive piling upof weld metal.

Slow up progress.

Wasted ller metaland time..


BadWelding CurrentAmp Too High

Weld Bead Face

SMAW 6010

Excessive spatter to becleaned off.

Undercuting alongedges weakens joint.

Irregular deposit..



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Shielded metal arc weldingAWS E6010 - General Purpose Electrode

Weld Bead Face

SMAW 6010

Weld bead veryirregular with poor

penetration..


An inefficient weld.

Wasted ller metal andtime..


BadWelding Speed

Too Fast

Weld Bead Face

SMAW 6010

Weld bead too small,with irregular contour.

Not enough weld metalin the cross-section.

Weld not strongenough.



BadWelding Speed

Too Slow

Weld Bead Face

SMAW 6010

Excessive bead width.

Too much timeconsumed.



BadArc Too Long

(High Voltage)

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GoodProper Current

Voltage & Travel

Weld Bead Face FCAW Self-shielding


No undercut,overlap or pile up



and labor cost.

Cross-section Fillet


Excessive spatterand porosity.

Weld bead excessivelywide and at.

Undercutting along edgesweakens joint.

Irregular weld bead contour.


BadWelding Current

Too High(Low Voltage)



Weld bead excessivelyconvex and narrow.

Difficult slag removal.


Cross-section Weld Bead Cross-section Weld Bead

BadWelding Current Too Low

(High Voltage)

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Flux cored arc welding -- self shielding

BadWelding Speed

Too Fast



Weld bead too smallwith irregular contour.

Not enough weld metalin cross-section.

Poor mechanicalproperties.

Undercut at toelines of llet.


BadWelding Speed

Too Slow



Excessive weld bead width.

Fillet with

unequal legs.










BadStick-out

Too Short

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Good

Proper CurrentVoltage & Travel

Weld Bead Face FCAW with shielding gas





and labor cost.



Weld bead excessivelywide and at.



Bad

Welding Current Too Low(High Voltage)

Bad

Welding Current Too High(Low Voltage)





Cross section weld bead

Cross section llet Cross section llet Cross section llet

Cross section weld bead Cross section weld bead

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Flux cored arc welding -- with shielding gas

BadWelding Travel Speed Too Fast






BadWelding TravelSpeed Too Slow



Overlapping withoutpenetration at edges.

Fillet withunequal legs.


BadInsufficient Shielding

Gas Coverage


Excessive spatter and porosity.

Weld bead very irregular withpoor penetration.

Weld metal not properlyshielded.

Wasted ller metal and time..

Cross section llet Cross section llet Cross section llet

Cross section weld bead Cross section weld bead Cross section weld bead

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GoodProper Current

Voltage & Travel

BadWelding Current

Too High(Low Voltage)

Weld Bead FaceGas metal arc welding





and labor cost.



Excessive piling up of weldmetal.


Irregular weld beadcontour.


Weld bead excessivelyconvex and wide.



BadWelding Current

Too Low

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Gas Metal Arc Welding

BadWelding Speed

Too Fast

BadWelding Speed

Too Slow

BadInsufficient Shielding

Gas Coverage







Excessive weld beadwidth.








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GoodProper Current

Voltage & Travel

Bad

Welding Current Too High

(Low Voltage)

Weld Bead Face Metal core welding


No undercut,

overlap or pile up



and labor cost.



Weld bead excessively

wide and at.





Wasted ller metal

and time.

BadWelding Current

Too Low

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BadWelding Speed

Too Fast

BadWelding Speed

Too SlowBadInsufficient Shielding

Gas Coverage








Overlapping withoutpenetration at edges.







Metal Cored Welding

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porous welds

Why1. Excessively long or short arc

length.2. Welding current too high.3. Insufficient or damp

shielding gas.4. Too fast travel speed.5. Base metal surface covered

with oil, grease, moisture, rust,

mill scale, etc.6. Wet, unclean or damagedelectrode.

What to do1. Maintain proper arc length.2. Use proper welding current.3. Increase gas ow rate and

check gas purity.4. Reduce travel speed.5. Properly clean base metal

prior to welding.6. Properly maintain and store

electrode.

cracked welds

Why1. Insufficient weld size.2. Excessive joint restraint.3. Poor joint design and/or

preparation.4. Filler metal does not match

base metal.5. Rapid cooling rate.6. Base metal surface covered with

oil, grease, moisture, rust, dirt ormill scale.

What to do1. Adjust weld size to part

thickness.2. Reduce joint restraint through

proper design.3. Select the proper joint design4. Use more ductile ller.5. Reduce cooling rate through

preheat.6. Properly clean base metalprior to welding.

undercuttingWhy1. Faulty electrode manipulation.2. Welding current too high.3. Too long an arc length.4. Too fast travel speed.5. Arc blow.

What to do1. Pause at each side of the

weld bead when using aweaving technique.

2. Use proper electrode angles.

3. Use proper welding current forelectrode size and weldingposition.

4. Reduce arc length.5. Reduce travel speed.6. Reduce effects of arc blow

Common Arc Welding Problems: Causes and Cures

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spatterWhy1. Arc blow.2. Welding current too high.3. Too long an arc length.4. Wet, unclean or damaged

electrode.

What to do1. Attempt to reduce the effect

distortionWhy1. Improper tack welding and/ or faulty joint preparation.2. Improper bead sequence.3. Improper set-up and

xturing.4. Excessive weld size.What to do1. Tack weld parts with

allowance for distortion.

lack of fusionWhy1. Improper travel speed.2. Welding current too low.3. Faulty joint preparation.

4. Too large an electrodediameter.5. Magnetic arc blow.6. Wrong electrode angle.

What to do1. Reduce travel speed.

2. Use proper bead sequencing.3. Tack or clamp parts securely.4. Make welds to specied size.

of arc blow.2. Reduce welding current.3. Reduce arc length.4. Properly maintain and store

electrodes.

2. Increase welding current.3. Weld design should allow electrode accessibility to all surfaces within the joint.4. Reduce electrode diameter.5. Reduce effects of magnetic

arc blow.6. Use proper electrode angles.

overlappingWhy1. Too slow travel speed.2. Incorrect electrode angle.3. Too large an electrode.

What to do1. Increase travel speed.2. Use proper electrode angles.3. Use a smaller electrode size.

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poor penetration

Why1. Travel speed too fast.2. Welding current too low.3. Poor joint design and/or

preparation.4. Electrode diameter too large.5. Wrong type of electrode.6. Excessively long arc length.

What to do

Common Welding Problems: Causes and Cures

1. Decrease travel speed.2. Increase welding current.3. Increase root opening or

decrease rootface.4. Use smaller electrode.5. Use electrode w/deeper

penetration characteristics.6. Reduce arc length.

magnetic arc blow

Why1 Unbalanced magnetic eld

during welding.2. Excessive magnetism in

parts or xture.What to doI. Use alternating current.2. Reduce welding current and

arc length.3. Change the location of the

work connection on theworkpiece.

inclusion

Why1. Incomplete slag removal

between passes.2. Erratic travel speed.3. Too wide a weaving motion.4. Too large an electrode.5. Letting slag run ahead of arc.6. Tungsten spitting or sticking.

What to do1. Completely remove slag

between passes.2. Use a uniform travel speed.3. Reduce width of weaving

technique.

4. Use a smaller electrode size forbetter access to joint.5. Increase travel speed or

change electrode angle orreduce arc length.

6. Properly prepare tungsten anduse proper current.

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Check-Points for Quality Welding

The future of welding and the future of the welders security rest upon quality weld-ing. Public confidence in welding has been built up through the satisfactory serviceof millions and millions of welds. Public confidence can quickly be destroyed by acatastrophe that could be caused by a defective weld. Adherence to the followingrules will insure quality welds and the future of the welding industry as well asyour own job security.

1. Use only high quality welding machines, electrodes end welding

accessories.2. Know the base material that you are working on.3. Select the proper welding process to give the highest quality welds on thebase material to be used.4. Select the proper welding procedure to meet the service requirement of thefinished weldment.5. Select the correct electrode for the job in question. See additional informationconcerning this elsewhere in this booklet.6. When preheating is specified or required make sure that the temperaturerequirements are met. In any case do not weld on material below 32 F, withoutfirst preheating.7. Clean the base metal of all slag, paint, grease, oil, moisture, and any otherforeign materials.8. Remove weld slag and thoroughly clean each bead prior to making the nextbead or pass.9. Do not weld over cracks or porous tack welds. Defective tack welds shoud beremoved prior to welding.10. Be particularly alert to obtain root fusion on the first pass of fillet and groovewelds.

11. When root gaps of groove welds are excessive, build up one side of the jointprior to welding the pieces together.12. When the root gap is excessive in fillet welding, be sure to increase the sizeof the fillet weld the amount of the root gap in order to maintain the strengthrequirement. In some cases it is an advantage to make a groove weld in order toavoid extremely large fillets.13. Inspect your work and immediately remove any defective weld and replaceit.14. Observe the size requirement for each weld and make sure that you meet or

slightly exceed the specified size.15. Make sure that the finished appearance of the weld is smooth and that overlapsand undercuts have been properly repaired. Remember that many people judgethe strength of a weld merely by its external appearance.

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Welding Arc Welding Travel Nozzle

Change Variable Voltage Current * Speed Angle Tip-to-work Required (see footnote) Deeper 1Increase 3 TrailingPenetration Max. 25Shallower 1Decrease 3LeadingPenetration

Larger 1Increase 2DecreaseBead

Smaller 1Decrease 2IncreaseBead

Higher 1Decrease 3 TrailingNarrower Bead

Flatter 1Increase 290 orWider Bead Leading

Faster 1Increase Deposition Rate Slower 1Decrease Deposition Rate

Troubleshooting Guide for Semiautomatic Wire W

BeadHeight

andbeadwidth

Key: (1) First Choice, (2) Second Choice, (3) Third choice, (4) Fourth Choice, (5) Fifth Choice

Note: Same adjustment is required for wire feed speed. * When these variables are changed, the wire feed speed must be adjusted so that the welding current remains cons See deposition rate of welding variables section. This change is especially helpful on materials 20 gage and smaller in thickness.

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Types of joints

Types of Welds

Variations of grooves

Butt Corner Lap

Edge T-Joint

Plug Slot

Edge

Fillet

Arc Seam

Surfacing

Groove

Square Single-J Single-Bevel

Single-V Single-U

Flare-V Flare-Bevel

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Welding Codes and Qualication of Welders

Before a welder can begin work on any job covered by a welding code, qualicationunder the code that applies is required. Many different codes are in use and it isrequired that the specic code is referred to when taking qualication tests. In

general the following type of work is covered by codes: pressure vessels and pressurepiping, highway and railway bridges, public buildings, tanks and containers that willhold ammable or explosive materials, cross country pipelines, aircraft, ordinancematerial, ships and boats, and nuclear facilities. A qualied welding procedure isnormally required. Qualication is obtained differently under the various codes. Qualication un-der one code will not necessarily qualify a welder to weld under a different code.Qualication for an employer will not allow the welder to work for another employer(except in cases where welders are qualied by an association of employers). If thewelder uses a different process or if the welding procedure is altered drastically,

requalication is required. In most codes, if the welder is continually welding withthe qualied procedure, welding requalication is not required, providing the workperformed meets the quality requirement. An exception is the military aircraft codewhich requires periodical requalication. Qualication tests may be given by responsible manufacturers or contractors. The welding procedure must be qualied before the welders can be qualied. To become qualied, the welder must make specied welds using the qualiedwelding procedure.

Welding Positions

lletweld

grooveweld

Flat Horizontal

throat of weldvertical

axis of weldhorizontal

(1F) (2F)

(1G) (2G)

axis of weldhorizontal vertical

plate

horizontal plate

plates and axis of pipe horizontal

pipe shall be rolled while welding

plates and axisof pipe vertical

test position at

test position

horizondal

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The welding procedures include information such as : process, base metal,thickness, electrode type position and joint design. In government specications,a government inspector may witness the making of weld specimens. Specimensmust be properly identied and prepared for testing.

The most common test is the guided bend test. In some cases radiographic(x-ray) examinations, fracture test or other tests are employed. Satisfactory comple-tion of test specimens, providing they meet acceptability standards, will qualify thewelder for specic types of welding. The welding allowed depends on the particularcode. In general, the code indicates the range of thicknesses and the alloys whichmay be welded, and the positions which may be employed. The qualication of welders is an extremely technical subject and cannot beadequately covered in this short publication. The actual code must be obtainedand studied prior to taking the test.

The most widely used codes are: Structural Welding Code - AWS D1.1; Weldingand Brazing Qualications - Section IX of the ASME Boiler and Pressure VesselCode; Standard for Welding Pipelines and Related Facilities - API 1104; AmericanNational Standard Code for Pressure Piping - ANSI B31.1; American Bureau ofShipping; Federal and Military Specications. These codes can be obtained fromthe sponsoring association.

Vertical Overhead

(3F)(4F)

(3G)

(4G)

(5G)

(6G)

vertical plate

axis of vetical plate

vertical plate

axis of weld horizontal

platesvertical

axis of weld vertical

plateshorizontal

45 pipe shall not beturned or rolled while welding

horizontal plate

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Welding SymbolsAWS welding symbols are the shorthand of welding. They

enable the engineer and draftsman to convey completeinstructions-for-welding to the welder on blueprints anddrawings.

Company-wide use of welding symbols will result in the fol-lowing advantages:

1. Control of specific design instruction tothe shop regarding weld sizes and plate edge

preparation, eliminating the tendency for over-welding or under welding (resulting in eitherincreased production costs or unsafe fabrica-tion) because of lack of definite information.

2. Elimination of unnecessary details on draw-ings when such detail is for the sole purpose ofindicating weld sizes and specifications. Weldingnotes will be minimized.

3. Establish a common understanding of designintent and requirements between engineering,shop, inspection, customers representativesand code inspection authorities. The benefitsof this advantage are readily apparent.

4. Standardization, not only within the com-pany but industry-wise as well. AWS weldingsymbols are a national standard and are usedworldwide.

The symbols shown on the following pages arefrom Standard Symbols for Welding, Brazing,and Nondestructive Examination, A2.4, pub-lished by the American Welding Society.

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Welding Symbols

Type of WeldArrowSide

OtherSide

BothSides

No ArrowSide or

Other SideSignicance

Fillet

Plug

Spot or Projection

Stud

Seam

Back or Backing

Surfacing

Edge

Square

V

Bevel

U

J

Flare-V

Flare-Bevel

Scarf forBrazed Joint

not used

not used

not used

not used

not used

not used

not used

not used

not used

not used

not used

not used

not used

Groove

Weld

s

not used

not used

not usednot used

not used

GrooveWeld Symbol

GrooveWeld Symbol

not used

not usednot used

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Typical Welding Symbols

Unequal double lletwelding symbol

Single V-groovewelding symbol

Single V-grooveweldingsymbol indicatingdepth of preparation

Staggeredintermittent llet welding

symbol

size (lengthof leg)

Desired Weld Symbol

locate weldsat ends of Joint

SymbolDesired Weld

length of segments

pitch (distance

between centers)of segments

Chainintermittent

llet weldingsymbol

Desired Weld Symbol

locate weldsat end of joint

length of segments

pitch (distancebetween centers) ofsegments

Desired Weld Symbol

root openinggroove angleroot opening

Desired Weld Symbol

(5/8) weld size

groove angle

depth of preparation

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Double-bevelgroove weldingsymbol

Plug weldingsymbol

Slot weldingsymbol

Spot weldingsymbol

Supplementary Welding SymbolsWeld AllAround

FieldWeld

Melt-thru

ConsumableInsert

BackingSpacer

Flush or

Flat

Contour

Convex Concave

Desired Weld Symbol

Desired Weld Symbol

Desired Weld Symbol

groove angleOmission of sizedimen-

sion indicatesa total depthof chamferingequal tothickness ofmembers

Desired Weld Symbol

rootopening

size (diameter ofhole at root)

depth of lling ininches

included angle ofcountersink

depth of lling ininches

included angle ofcountersink

orientationmust beshown indrawing

GTAW

Size (diameter of weld)strength in lb. per weldmay be used insteadProcess reference must beused to indicate processdesiredPitch (distance betweencenter) of welds

Number of welds

1/2 1/245

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Typical Welding Symbols

Symbol to indicatesingle-pass back weld

Double-V-grooveweld indicating a

spacer is to be used

Single V-groove weldindicating a backingstrip is to be used

Size of surfacebuilt up by welding

Symbols with multiplereference lines

Edge weld symbol

Desired Weld Symbol

Groove weld made before

welding other side

Desired Weld Symbol

Desired Weld

Desired Weld Symbol

Symbol

Symbol

back weld

Note: Material and dimensionof spacer as specied

See Note

spacer

backing strip

R = Removedafter welding

Size (thicknessof a surfacingweld)

First operationshown on refer-ence line nearestarrow. Secondoperation orsupplementarydata. Third operation ortext information.

Edge weld size

1/8

Desired Weld

Desired Weld

Symbol

R

1 /32

1/8

1st

2nd3rd

1 /32

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General Welding Safety

For Goggles or HelmetOperation Shade Number

Soldering 2 Torch Brazing 3 or 4Oxygen Cutting up: to 1 inch 3 or 4 1 to 6 inches 4 or 5 6 inches and over 5 or 6Gas Welding up to 1/8 inch 4 or 5 1/8 to 1/2 inch 5 or 6 1/2 inch or over 6 or 8Shielded Metal Arc Welding (SMAW, Stick)

1/16, 3/32, 1/8, 5/32, inch electrodes 10Nonferrous Metal WeldingGas Megal Arc Welding (GTAW, TIG) 11

Operation Shade Number

Gas Metal Arc Welding (GMAW, MIG) 11 1/16, 3/32, 1/8, 5/32 inch electrodesPlasma Arc Welding (PAW)

Ferrous Metal WeldingGas Tungsten Arc Welding (GTAW, TIG)Gas Metal Arc Welding (GMAW, MIG) 11 1/16, 3/32, 1/8, 5/32 inch electrodesPlasma Arc Welding (PAW)

Shielded Metal Arc Welding (SMAW, Stick)1/16, 7/32, 1/4 inch electrodes 12

5/16, 3/8 inch electrodes 14

Essentially, welding is not a hazardous occupation if proper precautionarymeasures are always observed. This requires continuous awareness ofpossibilities of danger and habitual safety precaution by the welders. They have an obligation to learn safe practices, to obey safety rulesand regulations, and to work in a safe manner. It is the responsiblity ofsupervisors to enforce safety rules and regulations set forth in ANSI Z49.1available from http://www.aws.org. The Occupational Safety and Health Administration (OSHA) requires thatemployers must have a comprehensive hazard communication program

to inform employees about hazardous substances that might be used inthe workplace. The purpose of the Material Safety Data Sheets (MSDS)is to explain the hazards involved in handling/using products such aswelding consumables and the precautionary measures which must beput in place for safe welding.

Safety Precautions for Arc Welding

1. Make sure your arc welding equipment is installed properly andgrounded and is in good working condition.2. Always wear protective clothing suitable for the welding to be done.3. Always wear proper eye protection when welding, cutting, or grinding.Do not look at the arc without peoper eye protection.

4. Avoid breathing the air in the fume plume directly above the arc.5. Keep your work area clean and free of hazards. Make sure that noammable, volatile, or explosive materials are in or near the work area.6. Handle all compressed gas cylinders with extreme care. keep caps onwhen not in use.

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7. Make sure that compressed gas cylinders are secured to the wall orother structural supports.8. When compressed gas cylinders are empty, close the valve and mark

the cylinder empty.9. Do not weld in a conned space without taking special precautions.10. Do not weld on containers that have held combustibles without tak-ing special precautions.11. Do not weld on sealed containers or compartments without providingvents and taking special precautions.12.Use mechanical exhaust at the point of welding when welding lead,cadmium, chromium, manganese, brass, bronze, zinc, or galvanized steel,and when welding in a conned space.13. When it is necessary to weld in a damp or wet area, wear rubber bootsand stand on a dry, insulated platform.14 Do not use cables with frayed, cracked or bare spots in the insula-tion.15 When the electrode holder is not in use, hang it on brackets provided.Never let it touch a compressed gas cylinder.16. Dispose of electrode stubs in proper containers since stubs on theoor are a safety hazard.17. Shield others from the light rays produced by your welding arc.18. Do not weld near degreasing operations.19. When working above ground, make sure that scaffold, ladder or worksurface is solid and properly secured.20. When welding in high places, use a safety belt or lifeline.

Safety Precautions for Oxyacetylene Welding and Cutting

1. Make sure that all gas apparatus shows UL or FM approval, is installedproperly, and is in good working condition. Make sure that all connectionsare tight before lighting the torch. Do not use a ame to inspect for tight joints. Use soap solution to detect leaks.2. Always wear protective clothing suitable for welding or ame cut-ting.3. Keep work area clean and free from hazardous materials. When amecutting, sparks can travel 30 to 40 feet (10 to 15 m). Do not allow amecut sparks to hit hoses, regulators, or cylinders.4. Handle all compressed gas cylinders with extreme care. Keep cylindercaps on when not in use.5. Make sure that all compressed gas cylinders are secured to the wallor to other structural supports. Keep acetylene cylinders in the verticalposition.

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6. Store compressed gas cylinders in a safe place with good ventilation.Acetylene cylinders and oxygen cylinders should be kept apart.7. When compressed gas cylinders or fuel gas cylinders are empty, close

the valve and mark the cylinder empty.8. Use oxygen and acetylene or other fuel gases with the appropriatetorches and only for the purpose intended.9. Avoid breathing the air in the fume plume directly above the ame.10. Never use acetylene at a pressure in excess of 15 psi (103.4 K Pa). Higherpressure can cause an explosion.11. Never use oil, grease, or any material on any apparatus or threadedttings in the oxyacetylene or oxyfuel system. Oil and grease in contactwith oxygen may cause spontaneous combustion..12. Do not weld or ame cut in a conned space without taking specialprecautions.13. When assembling apparatus, crack gas cylinder valve before attachingregulators (cracking means opening the valve on the cylinder slightly, thenclosing.) This blows out any accumulated foreign material. Make sure thatall threaded ttings are clean and tight.14. Always use this correct sequence and technique for lighting a torch: (a) Open acetylene cylinder valve. (b) Open acetylene torch valve 1/4 turn. (c) Screw in acetylene regulator, adjusting valve handle to workingpressure. (d) Turn off acetylene torch valve (you will have purged the acetyleneline). (e) Slowly open oxygen cylinder valve all the way. (f ) Open oxygen torch valve 1/4 turn. (g) Screw in oxygen regulator screw to working pressure.

(h) Turn off oxygen torch valve (you will have purged the oxygen line). (i) Open acetylene torch vlave 1/4 turn and light with lighter (use friction-type lighter or special provided lighting device only). (j) Open oxygen torch valve 1/4 turn. (k) Adjust to neutral ame.15. Always use this correct sequence and technique of shutting off atorch: (a) Close acetylene torch valve rst. Then close oxygen torch valve. (b) Close cylinder valves -- the acetylene valve rst, then the oxygenvalve. (c) Open torch acetylene and oxygen valves (to release pressure in theregulator and hose). (d) Back off regulator adjusting valve handle until no spring tension isfelt. (e) Close torch valves.

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16. Use mechanical exhause when welding or cutting lead, cadmium,chromium, manganese, brass, bronze, zinc, or galvanized steel.17. If you must weld or ame cut with combustible or volatile materials

present, take extra precautions, make out hot work permit, and providefor a lookout, etc.18. Do not weld or ame cut on containers that have held combustibleswithout taking special precautions.19. Do not weld or ame cut into sealed container or compartment withoutproviding vents and taking special precautions.20. Do not weld or cut in a conned space without taking special precau-tions.

There must be continual vigilance over safety conditions and safety haz-ards. Safety meetings should be held regularly. The safety rules should bereissued annually and they must be completely understood and enforced.Safety rules and precautions should be posted in the welding shop.

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Welding MetalsAlmost every metal known can be welded by one process or an-other. The arc welding processes used primarily for steels includeShielded Metal Arc Welding(SMAW), Gas Metal Arc Welding(GMAW)and Flux Cored Arc Welding(FCAW). Welding electrodes shouldbe selected based on the composition of the steel to be welded.Steels are manufactured and specied in many different ways. Ingeneral, steels are classied according to the carbon content, thatis, low carbon, medium carbon or high carbon steels. In addition

they are also classied according to the type of alloy employed,such as chrome moly, nickel, manganese, etc. Steels are also soldunder many trade names and specications. The following is a brieflisting of some of the specications in use.

ASTM The American Society for Testing and Materials sponsorsspecications covering many different types of steels. Their speci-

cations may be prexed by their acronym of ASTM.API The American Petroleum Institute species steels usuallyemployed in pipe.

ASME The American Society of Mechanical Engineers speci-es steels but in general utilize the same numbers as the ASTMspecications.

Military and Federal Specication The Government specicationsare usually indicated by the letters MIL or QQ.

SAE and AISI The Society of Automotive Engineers and the Ameri-can Iron and Steel Institute have a very complete listing of steelsusing code numbers that indicate the steel composition. Stainless

steels are covered by the AISI numbers.

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Steel Available for WeldingSteel warehouses located in most larger cities carry stocks of the popular sizes and shapes ofmild steel. Large requirements can be obtained direct from steel mills. The following is a listing

of the various shapes, sizes and types usually available.Shapes (Composition usually to ASTM Specs) American Standard Beams 6 to 24 Specied: Depth by wt. per foot Wide Flange Shapes 6 to 36 Specied: Depth by wt. per foot American Standard Channels 3 to 18 Specied: Depth by wt. per foot Angles (equal and unequal legs) 1 x 1 to 8 x 8 leg by leg by thickness Structural Tees-These are split beams or wide ange shapes. Misc. Light and Junior Sections Lighter and thinner than above. Misc. Sections such as Zees, pilings, rails, etc.

Bars (Composition usually to AISI or SAE Specs) Flats thickness 1/4 to 4 by width 3/8 to 8 Square 1/4 sq.: to 2 3/4 sq. Special 1/2 sq. to 6 square. Rounds 3/16 dia. to 2 7/8 dia. Special 3/8 dia. to 9 1/2 dia. Half Rounds 1/2 to 3 (across diameter) Hexagons 1/2 to 1 3/8 (across ats)

Tubular (Composition usually to ASTM or API Specs) Pipe Specied by nominal pipe diameter in inches. Wall thickness specied by Schedule Number or by Standard, Extra Strong or Double Extra Strong Round Tubing Seamless Mechanical 3/16 dia. O.D. wall thickness 24 gage to 16 gage to 10 dia. O.D. wall

thickness 1/4 to 1 1/8. Round Tubing Welded Mechanical

3/8 dia. O.D. wall thickness 22 gage to 16 gage, to 6 dia. O.D. wall thickness 11 gage to 1/4Square Tubing Mechanical and Structural Welded or Seamless

1/2 to 1/2 wall thickness 20 gage to 16 gage, to 4 x 4 wall thickness11 gage to 3/16.

Rectangular Tubing Welded Mechanical 1 1/2 x 1 wall thickness 14 gage, to 4 x 2 wall thickness 3/16.

Sheet and Plates (Composition usually to ASTM or chemistry for end use) Widths beyond 8 inches are considered sheet or plate thickness above 3/16

considered plates. Sheets specied by gage thickness. Plates specied by thicknessin inches or weight per square foot.

Misc. Warehouses offer many other forms of steeel such as dished heads for tanks, reinforc- ing rods, etc. and ame cutting service.

Note Trade names are often used to identify steel compositions.

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Metal

appearance

magnetic

chisel

fracture

ame

spark*

Test

Low carbonsteel

Dark grey

Strongly magnetic

Continuous chip,smooth edges,

chips easily

Bright grey

Melts fast, becomesbright red before

melting

Mediumcarbon

steelDark grey

Strongly magnetic

Continuous chip,smooth edges,

chips easily

Very light grey

Melts fast, becomesbright red before

melting

High carsteel

Dark gr

Strongly mag

Hard to chCan be contin

Very light g

Melts fast, becbright red be

melting

Cir. x R.P.M. 12

= S.F. per minuteLong Yellow CarrierLines (Approx. 20%carbon or below)

Yellow Lines BrigVery Clear Numer

Burst (approx. carbon and abo

* For best results, use at least 5,000surface feet per minute on grindingequipment. Yellow lines

Sprigs Ver y Plain Now(Approx. .20% to .45%

carbon)

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appearance Dull cast surface Bright, Silvery, Dull grey, EvidenSmooth of sand mo

magnetic Nonmagnetic Depends on Strongly exact analysis magnetic

chisel Extremely Continuous chip, Small chips abohard to chisel Smooth, 1/8 in., Not eas

Bright color chip, Brittfracture Course grained Depends on type, Brittle

Bright

ame Melts fast, Melts fast, Melts slowlBecomes bright Becomes bright Becomes dull

red before melting red before melting red before melting

Metal Test

Cir. x R.P.M.12

= S.F. per minute

Spark*

Manganesesteel

Stainlesssteel

Castiron

1 . N i c k e l - b l a c k s h a p eclose to wheel; 2. Moly-shortarrow shape tongue (only); 3.Vanadium- long spearpoint,tongue(only).

Red carrier l(very little carbon

Bright whitefan-shaped burst

*For best results, use atleast 5,000 surface feetper minute on grindingequipment.

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Welding is the most economical method of joining metals. However, we should allbe on the lookout for ways to save time and materials to make welding the mostadvantageous. The following hints will help to lower arc welding costs.

Material Select an easily weldable material that will not require expensive elec-trodes or complicated welding procedures.

Joint Design On heaviermaterial, double bevel and vee jointssave considerable weld material. Of

course, it is necessary to be able toweld both sides.

Rolled Sections and Forming Use bends and rolled angle channels, etc., toreduce the number of weld joints required.

Distortion Control Use wandering or back step sequence to reduce warpageand keep material in line to reduce the machining necessary.

Proper Fit-up Wide gaps between pieces to be welded waste weld metal. Fil-lets must be increased by the amount of gap to maintain strength.

Fillet Weld Size Fillet weld size mustbe closely controlled. Doubling the sizeof a fillet requires four times as muchweld metal.

Overwelding and Reinforcement Extra re-inforcement and unequal legged fillets wasteweld metal. The crown or reinforcement addslittle to the strength of the weld.

Positioning Position the job for flat welding if at all possible. This is the mostefficient position. It allows use of larger electrodes. It is easier and more comfort-able for the welder.

Arc Length Keep a short arc or low voltage. This will concentrate all of the weldingcurrent in the joint and will minimize spatter.

Electrode Type Select the higher production type electrode for cost savings. Seedescription in electrode section of booklet.

Cost Saving Hints

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Electrode Size Use the largest size electrode possible. Large size stick electrodes cost lessand increase the welding speed. This is generally true in wire electrodes.

Stub Ends Burn electrodes to a 2 inch length or use the continuous wire electrodes.

Machine Efficiency Match the welding machine to the job. Too small a machine is inef-cient since it may be operated beyond its capacity. Machines should be checkedperiodically for loose connections, wire, etc.

Cable Size and Length Too small welding cable will heat up. Heat produced in the cableis wasteful. It is not doing useful work. Cables that are too long waste power, and causesa voltage drop at the holder. Excessive cable wrapped in coils is also very wasteful. Usethe proper size cable and keep cable to reasonable lengths for efficiency.

Loose Connections Check cables, connectors, electrode holders for hot spots. Looseconnections or broken wire will show up as hot spots which waste power. Correctthem when found.

Use Largest Size Electrode Possible

recommendedminimumcable sizes

Welding Current (amps.) Cable Size (No.)

100 4 150 2 200 2 250-300 1/0 300-450 2/0 500 3/0 600 4/0

electrodesize 5 10 15 20 25 30

3/32

1/8

5/32

3/16

1/4

5/16

feetof jointwelded

per hour(approx.)

3/8

Butt Weld

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8 Factors to ConsiderWhen Selecting Electrodes

1. Base Metal Strength Properties

2. Base Metal Composition 3. Welding Position 4. Welding Current 5. Joint Design and Fit-up 6. Thickness and Shape of Base Metal

7. Service Condition And/Or Specications 8. Production Efficience and Job Conditions

1. Base Metal Strength PropertiesKnow and match mechanical properties. Mild steel generally E-60XX or E-70XXelectrodes match base metal. Low alloy steel select electrodes that match base

metal properties.2. Base Metal CompositionKnow and match composition. Mild steel any E-6OXX or E-70XX electrode issatisfactory. Low alloy steel select electrode that most closely matches basemetal composition.3. Welding PositionMatch electrode to welding position encountered.4. Welding CurrentMatch power supply available. Some electrodes are designed for direct current (DC);others, alternating current (AC); some, either. Observe correct polarity.5. Joint Design and Fit-upSelect for penetration characteristic digging, medium, or light. No beveling ortight t-up use digging. Thin material or wide root opening light, soft arc.6. Thickness And Shape of Base Metal To avoid weld cracking on thick and heavy material of complicated design, selectelectrode with maximum ductility. Low hydrogen processes or electrodes arerecommended.7. Service Condition And/Or SpecicationsDetermine service conditions low temperature, high temperature, shock loading

match base metal composition, ductility and impact resistance. Use low hydrogenprocess. Also, check welding procedure or specication for electrode type.8. Production Efficiency And Job ConditionsFor high deposition and most efficient production under at position requirements,select high iron powder types or large diameter wires: For other conditions, youmay need to experiment with various electrodes and sizes.

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Metal Cored WireEdited from an article by Steve Barhorst and

used with permission from Hobart Brothers Company.

Metal cored wire is a tubular electrode that consists of ametal sheath and a core of various powdered materials,primarily iron. The core contributes almost entirely to thedeposited weld metal.

WHAT APPLICATIONS BENEFIT FROM METAL-CORED

WIRE? Solid wire in the at and horizontal positions where spraytransfer is being used.

Many gas shielded, ux cored, and some submerged arcapplications.

Multiple-pass robotic and automatic welding Other applications determined by weld cost calculations

or quality issues (compensating for poor t-up, beadappearance, burn-through).

WHY USE METAL CORED WIRE? Can save $100 to $200 for every 100 pounds of weld

metal deposited. High deposition rates and travel speeds. No slag; almost no spatter.

Little or no post-weld cleanup or cleaning betweenpasses. Excellent side-wall fusion and root penetration. Ability to bridge part gaps without burn-through. Ability to weld thin materials at high amperages without

burn-through. Capability to weld out-of-position with pulsed spray or

short-circuit transfer. Compliance with ABS, DNV, API, LRS, ANSI, and AWS

standards.

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SOLID WIRE

Metal Core lacks deeper penetration.

METAL CORE WIRE

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Oven Storage and Reconditioning of Filler Metals

StoragItem Designation Contents of Ope

Pipemaster 60, 70, 80, 90, 335A, 333C Dry at room tem

12, 1139, 447A, 447C, 14A, 27, 24 125

718,716C, 18AC, 418, 718MC, 7018C1, 8018C2, 8018C3, 8018B2, 80182L 300F

9108M, 9018B3, 9018B3L, 10 018M, 10018D2, 10018M, 12018M 300

Smootharc, and Smootharc Plus Stainless Stick Electrodes 250F

Cast Iron electrodes 150 Excel-Arc, FacCOR, GSF, FabCO, Fabshield, Fabloy, Formula XL Dry at room te

Welding electrodes and wires may bedamaged by atmospheric moisture. Thefollowing table recommends proper storageconditions, and time and temperaturefor reconditioning electrodes that haveabsorbed excessive moisture.Notes: Pallets and unopened cartons ofelectrodes and wires should be storedaway from exposure to water in the formof rain, snow,

spray, or humidity. Only hermetically-sealedcans are safe against these condit ions.

Damaged cartons permit entry of dampair which may be picked up by the productand lowe r its quality. Humidity below 50%should be avo ided for XX10, XX11, XX12,and XX13 covered electrodes. At no timeshould these classes of electrodes be storedin an oven above 130F.

Thein tshoushou

* Be sure that electrodes or wires are properly removed from packaging that may be damaged.

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Size of llet Steel deposited PounL per linear foot per line

(in inches) of weld (lbs.) Stick* (SMAW)

1/8 0.027 .049 3/16 0.063 .114 1/4 0.106 .193 5/16 0.166 .302 3/8 0.239 .434

1/2 0.425 .773 5/8 0.663 1.205 3/4 0.955 1.736 1 1.698 3.087 *Includes scrap end and spatter loss.

The following tables will help you estimateelectrode quantity and cost for a variety

of joints. The base s for the tabulations areexplained below.Should you encounter a va riation in conditionsor joint preparation that is not shown in thetables, substitute appropriate figures in theW=D/(1-L) formula and calculate it.Electrode requirements have been calcu latedas follows:W = D

1-LW = Weight of electrode s requiredD = Weight of steel depositedL = Totalelectrode losse s

To arrive at the weight of steel deposited, itis necessary to calculate first the volume ofdep osited metal (area of the groove multipliedby the length). Then this volumetric value isconverted to weight by the factor 0.283 poundsper cubic inch for steel. Where weld re inforcementis involved, it is added to the requiremen ts for net,

Horizontal Fillet Weld

L

L

How to Calculate Filler M etal Consumptiounre Thethe joinefficdepoby .

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Joint dimensions Steel deposited per linear (inches) foot of weld (lbs.) per linear foot of weld* (approx

Metal Bead Root With Thickness Width Open Without reinforcement

T B G reinforcemen

(R**=0.07) 3/16 3/8 0 0.088 1/16 0.020 0.109 1/4 7/16 1/16 0.027 0.129 3/32 0.039 0.143 5/16 1/2 1/16 0.033 0.153 3/32 0 .050 0.170 1/8 1/4 0 0.119 1/32 0 .013 0.132 3/16 3/8 1/32 0.020 0.199 1/16 0.0 40 0.218 1/4 7/16 1/16 0.053 0.261 3/32 0.0 80 0.288

Joint dimensions Steel deposited per linear (inches) foot of weld (lbs.)

Meta l Bead Root With Thickness Width Open Without reinforcement

T B G reinforceme(R**=0.08) 1/4 0.207 1/16 0.085 0.143 5/16 0.311 3/32 0.173 0.258 3/8 0.414 1/8 0.282 0.394 1/2 0.558 1/8 0.489 0.641 5/8 0.702 1/8 0.753 0.942 3/4 0.847 1/8 1.088 1.320 1 1.138 1/8 1.930 2.240

T

*Includes scrap end and spatter loss. **R=Height of reinforcem

Square Groove Butt Joints welded one side

V Groove Butt Joint

BR=0.07

T

R=0.07

welded two sidesif root of top weld is chipped or ame gouged andwelded, add 0.07 lb. to steel deposited (equivalent

to approx. 0.13 lb. of electrodes).

60B

1/8

G

R=.008

Material Thickness

T

BeadWidth

B

RootOpenings

G

G

T

B R=0.07

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Shielding Gases and Their Uses Shielding Gas GMAW GTAW GTAW

Reaction and FCAW and PAW

Pure Gases

Argon, Ar Inert Nonferrous All Metals

Helium, He Inert Nonferrous Al, Mg, and Cuand alloys

Carbon dioxide, CO 2 Oxidizing Mild and low-alloy Not used steels, some

stainless steels

Two-ComponentMixtures

Argon mixturesArgon + 20-50% He Inert Al, Mg, and Cu Al, Mg, and alloys

and alloys

Argon + 1-2% CO 2 Oxidizing Stainless and Not used low-alloy steels

Argon + 3-5% CO 2 Oxidizing Mild, low-alloy, Not used and stainless steels

Argon + 20-30% CO 2 Slightly Mild and low-alloy Not used Oxidized steels, some

stainless steels

Argon + 2-4% He Reducing Not used Nickel and alloyand AustineticSS

Helium mixturesHelium + 25% Ar Inert Al and alloys, Al and alloys,

Cu and alloys Cu and alloys

CO2 mixturesCO2 + up to 20% O 2 Oxidizing Mild and low-alloy Not used steels (used in

Japan)

CO2 + 3-10% O 2 Oxidizing Mild and low-alloy Not usedsteels (used in Europe)

Three-Component

Mixtures Helium mixtures

He + 75% Ar +25% CO2 Inert Stainless steel and Not used

low-alloy steels

Argon mixtures Oxidizing Mild Steels Not usedAr + 3-10% O2 +15% CO2 (used in Europe)

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Position1. Flat, Horizontal, Vertical, Overhead2. Flat and Horizontal only4. Flat, Horizontal, Vertical Down, Overhead

Types of coating and current

Digit Type of Coating Welding Current 0 cellulose sodium DCEP 1 cellulose potassium AC or DCEP 2 titania sodium AC or DCEN 3 titania potassium AC or DCEP or DCEN 4 iron powder titania AC or DCEN or DCEP 5 low hydrogen sodium DCEP 6 low hydrogen potassium AC or DCEP 7 iron powder iron oxide AC or DCEP or DCEN 8 iron powder low hydrogen AC or DCEP E6020 iron oxide sodium AC or DCEP or DCEN

DCEP Direct Current Electrode PositiveDCEN Direct Current Electrode Negative

How AWS classies mild steel covered electrodes,SMAW process

E 7018-1 H4 RElectrode

Tensile in ksiPosition Type of coating and currentMeets lower temperature impact requirementsHydrogen: H4=less than 4ml/100gH8=less than 8 ml/100gMeets requirements of absorbed moisture test

AWS Electrode Classifcations& Comparative Indices

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Chemical composition of weld deposit Suffix C Mn Si Ni Cr Mo Va

A1 .12 .40 -.65* .40-.80 .40-.65 B1 .12 .90 .60-.80 .40-.65 .40-.65 B2L .05 .90 .8-1.00* 1.00-1.50 .40-.65 B2 .12 .90 .60-.90 1.00-1.50 .40-.65 B3L .05 .90 .8-1.00* 2.00-2.50 .90-1.20 B3 .12 .90 .60-.80* 2.00-2.50 .90-1.20 B4L .05 .90 1.00 1.75-2.25 .40-.65 B9 .08-.13 1.25 .30 1.0 8.00-10.50 . 85-1.2 .15-.30C1 .12 1.20 .60-.80* 1.00-2.75 C2 .12 1.20 * 3.00-3.75 C3 .12 .40-1.25 .80 .80-1.10 .15 .35 .05D1 .12 1.25-1.75 .60-.80* .25-.45 D2 .15 1.65-2.00 .6-.8* .25-.45 G 1.0 Min .80 Min .50 Min .30 Min .20 Min .10 MM** .10 .60-2.25* .60-.80* 1.40-2.50* .15-1.50* .25-55* .05

* Amount depends on electrode classication. Single values indicatemaximum, refer to AWS 5.5 for the different electrode classes.

** There are several different M classes. M classications are intended toconform to military specications.

E 80 1 8 - B2Electrode

Tensile in ksi

All Position

Chemical composition ofweld metal deposit

For AC or DCEP

How AWS classies low alloy covered electrodes

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AWS Class HOBART McKAY ESAB LINCOLN MUREX

E6010 Pipemaster Pro 60 ---- SW-10P PLUS 5P5P+

Pipemaster 60 6010 PM SW-10P 5P5P+

E6011 335A, 335C 6011 SW-14 FW 180, FW35 6011C

E6013 447A, 447C 6013 SW-15 FW 37 6013D

E6022 1139 FW 22

E7010-P1 Pipemaster 70 SW-710P SA HYP+

E7014 14A 7014 SW-14IP FW 47 7014

E7018 (AC) 18AC AA 7018AC 7018AC 7018AC

E7018-1 H4 418,718, 718MC SOFT-ARC 7018-1

E7018 H4R 418, 718, 718MC 7018 XLM AA 7018 Jetweld LH-70 7018MR

E7018-1H4R 418,718,718MC EX 7018-1MR,LH-75MR

E7018-1H4R(M) 718 MC AA 7018-M EX 7018M MR

E7024 Rocket 7024 7024 SW-24 Jetweld 3 7024

E8010-P1 Pipemaster 80 SW-810P Shield-Arc 80

Comparative Index of Mild Steel & Low Hydrogen

Hobart Diameter: 3/32 3/32 1/8 5/32 3/16 3/16 1/4 Type Length: 10 14 14 14 14 18 18

Pipemaster 60, 70, 80 30 17 12 8

335A, 335C 25 15 11 7

447A, 447C 25 15 10 7

14A 24 13 9 6

24 (-1) 10 7 4 2

XX18 (Iron Powder) 32 15 10 7 3

Stainless 31 13 9 4 3

Pieces Per Pound Arc Welding Electrodes

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AWS Class HOBART ESAB LINCOLN

E7018-A1 HOBALLOY ATOM ARCEXCALIBUR 7018 A1 7018-MO

7018-A1 MR

E8018-B2 HOBALLOY ATOM ARC Jet-LH8018 B2 8018-CM 8018-B2

MR

E8018-B2L HOBALLOY ATOM ARC

8018B2L 8108 - B2L

E8018-C1 HOBALLOY ATOM ARCEXCALIBUR

8018C1 8018-C1 8018-C1MR

E8018-C2 HOBALLOY ATOM ARC 8018C2 8018-N

E8018-C3 HOBALLOY ATOM ARCEXCALIBUR

8018C3 8018 8018-C3MR

E9018-B3 HOBALLOY ATOM ARC JET-LH9018B3 9018-CM 9018 B3

MR

E9018-B3L HOBALLOY ATOM ARC 9018B3L 9018-B3L

E9018-M HOBALLOY ATOM ARCEXCALIBUR

9018M 9018 9018MMR

E10018-D2 HOBALLOY ATOM ARC 10081D2 10018-MM

E11018-M HOBALLOY Atom Arc T

EXCALIBUR11018M 11018M

MR

E12018-M HOBALLOY Atom Arc 12018M 12018

Comparative Index of Low Alloy Electrodes

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Type of coating and current

E 308 x-1 5Electrode

Indicates what a weld madeby this electrode will have in it

Indicates any changesto the original alloyPosition

How AWS classies stainless steel coatedelectrodes, SMAW process

Dash Out of Bead Slag Spatter Transfer Operating BeadNumber Position Ripple Removal Level Type Current Prole

-x5 1(5/32) 3 3 3 Globular DCEP Convex

-x6 2(5/32) 2 2 2 Globular AC/DCEP Flat

-x7 3(3/16) 1 1 1 Spray AC/DCEP Concave

Suffix Changes Made or Additional Requirements

L Has a lower carbon content

H Limited to the upper range on the carbon content

Mo Molybdenum added pitting resistance, creep

strength, ferrite increased

Cb (Nb) Columbium added prevents corrosion just outside

of the weld bead

Ni Nickel added high temperature strength, corrosionresistance, added toughness

LR Low Residuals lower range for: C, Si, P, S narrowerrange: Cb and Mn

Additional Requirements

Note: Nb(Niobium) is the European name for Columbium.

Ratings: 1 = the best, 3 = the least

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How AWS classies stainless steelux-cored wires

Suffix Changes Made or Additional Requirements L Has a lower carbon content H Limited to the upper range on the carbon content Mo Molybdenum added pitting resistance, creep strength, ferrite increased Cb (Nb) Columbium added prevents corrosion just outside of

the weld bead Ni Nickel added high temperature strength, corrosion

resistance, added toughness Ti Titanium added prevents corrosion just outside of the

weld bead K Specially formulated for cryogenic temperature service

(less than -238F)

Indicates the shielding gas, if any

E 308 x T1 -1Electrode

Indicates what a weld madeby this electrode will have in it

Indicates any changesto the original alloy

Indicates that this is aux-core wire. Tubular

Position

Shielding Chart

Additional Requirements

Dash Number Shielding Gas Welding Current -1 CO2 DCEP

-3 None DCEP

-4 75% Ar/25% CO 2 DCEP

Note: Nb (Niobium) is the European name for Columbium.

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