process desc 1

7/25/2019 Process Desc 1

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Cold Rolling Cum Galvanizing Complex at Meramandali (Orissa)

Process Description

Cold Rolling Mill (CRM) Complex is a set of different sequential Processes includes the following

Operations/Processes.

1. HR litter!

Slitting seres three purposes (i) !R coils are aaila"le in width which are wider than the required

for Cold Rolling. #n order to ma$e them compati"le with the Cold Rolling facilities and the

requirement of the end product% these coils are required to "e slitted. (ii) hae the profile "eing

thic$er in the center and sloping down towards the edges. #n order to minimi&e the ariation in the

final output% it is imperatie that edges on "oth sides of the !R coils are trimmed.'his trimming /slitting is done with the !R Slitter. (iii) 'he !R coils aaila"le ma hae width ariation of the

order of upto * mm% so to get the uniform width these coils are slitted.

peci"ications!

+ ,ine Speed *-*-+** mpm

r"or diameter mm

0 Strip width range 1* 2 +3* mm

4 Strip thic$ness range +.5 2 5.** mm

Max coil weight 4. tons

5 Max no. of slits +

#. Pic$ling!

'he !R Coils% in their raw form% hae deposits of ferric oxide (Rust) and other similar

impurities on the surface. 6efore further processing these impurities are required to "e

remoed.

7or this purpose% the !R Coils after slitting are passed through a hot water "ath% "efore

"eing introduced in the pic$ling line. Pic$ing means cleaning of !R Strips in hdro

choleric acid tan$s. 8uring the process% the !R coils are passed% at a constant speed%through three/fie tan$s full of hdro choleric acid% with the help of roller fitted in these acid

tan$s. t the time of exit from the last tan$% "ecause of chemical reaction of the hdrochloric

acid with the steel% a corrosion in the steel occurs with a resultant loss of around *.9 to

*.19. fter this acid "ath% in order to proide the strip with an acid free surface% the !R

sheet is rinsed first in hot water and then fresh water in fie stages to remoe the carr-oer

acid from the strip. nd finall this strip is coated with a thin laer of rust preentie oil

after "eing dried " hot air "last% in order to aoid further oxidi&ation of the strip surface.


2/26


Process Description

peci"ication!

+ ,ine Speed *-+* mpm

:inding tension +* tons max

0 cid temp in pic$ling tan$ 3*-3 oC

4 :ater temp in rinse tan$s 1 2 3* oC

Coil :eight 03 tons

5 Strip 'hic$ness +.5 2 3.* mm

1 Strip :idth 1** - +5* mm

'his Pic$ling operation can "e controlled with the help of four factors;-

(i) 'he concentration of the acid in the pic$ling tan$% more the concentration faster will

"e the reaction and ice ersa. 'he concentration of acid aries from .9 at the

time of entr of !R coils into the first pic$ling tan$ to +39 at the time of exit from

the last tan$.

(ii) 'he temperature of the acid in the pic$ling tan$% more the temperature faster the

reaction will "e and ice ersa. 'he temperature of the acid is $ept a"out 3*-3oC in

all the tan$s.

(iii) Speed of the steel strip into the pic$ling tan$% more the speed lesser the pic$ling will

"e and ice ersa. 'he max speed can go upto +* meters per minute.

(i) 'he qualit of the steel strips to "e pic$led% more rust the strip will "e longer time it

will ta$e to "e pic$led and ice ersa.

#f the !R sheet remains in the acid "oth for a longer duration% it can results on oer pic$ling due to

excessie exposure to chemical reaction% and the !R sheet which hae passed through acid remain

exposed to air "efore entering the water tan$s% and due to oxidi&ation ma deelop rust on its

surface.'o aoid such occurrence the acid is drained out% in case of interruption in the plant

operation so that strip doesn


3/26


Process Description

%. &cid Regeneration Plant (&RP)!

'he RP (cid Regeneration Plant) regenerates hdrochloric acid from waste pic$le liquor from

the acid pic$ling line on the principle of prohdrolsis " appling fluidi&ed "ed technolog.

'he rinse water and the waste acid which are needed during the process are stored in the tan$ farm

and pumped to the regeneration.

Regenerated acid which is generated during this process is pumped to the shifting tan$ regenerated

acid inside the tan$ farm.

Capacit'! . m=/h

Products

(&) Regenerated &cid

!Cl > +3 wt9

() ron Oxide

quantit ? 41* $g/h

%.1 Gas cooling and preconcentration

fter the waste acid coming from the tan$ farm the liquor is directed into the liquid separator. 'heliquid separator is also the feeding "in for the preconcentrator feeding pumps% which circulates the

waste acid through the enturi eaporator.

6 this% the hot roast gas is cooled down from 3*@C to approximatel A3@C and dedusted. :hile

the solution is heated and concentrated% the latent heat of the roast gas is recoered.

'he liquid drops are separated from the gas in the liquid separator. 7rom the separator% the

concentrate is directed to the reactor. 'he liquid leel in the separator is controlled " the feed of

waste acid while the densit of the concentrate is controlled " adding rinse water. dding rinse

water is necessar to aoid crstalli&ing of iron chloride.

%.# Roasting process

'he concentrated solution is pumped into the reactor ia one acid lance from the wall onto the

fluidi&ed "ed. t the "ottom of the reactor a "urner sstem consisting of multiple tuere no&&les is

installed. 'he com"ustion air is deliered " the com"ustion air fan to the wind "ox cham"er. 7rom

this cham"er the air enters the reactor ia the "urner no&&les. #nside the "urner no&&les fuel and air

are mixed and the com"ustion ta$es place directl within the "ed thus fluidi&ing the oxide

granulates and generating the heat for water and free acid eaporation and iron chloride

decomposition according to the following reaction equation.

7eCl B !O B O 7eO0 B 4 !Cl

7eCl0 B 0 !O 7eO0 B 5 !Cl

certain amount of excess air deliers the oxgen needed for roasting reaction. #nside the reactor


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Process Description

the temperature is controlled " the feed rate of acid and is $ept constant oer "ed and free"oard

due to good mixing of particles and gas.

'he oxide produced forms laers (onion structure) on the existing particles. 'he fines produced in

the reactor are carried out together with the reaction gas and are separated in a cclone and reccled

"ac$ into the reactor.

#MPOR'D' DO'E; !ot part of the plant is protected " refractor on the inside of equipment

(reactor% cclone% roast gas duct). Refractor material must "e handled with care and shall alwas

hae the same temperature. 7or that it is strictl recommended that the plant is "eing operated

smoothl% and heat up/ cool down operations shall not "e done more often than fie times per ear%

as otherwise there will "e immoderate wear.

%.% Oxide *andling

'he oxide is discharged into a cooled screw coneor and transported " a "uc$et eleator to the

oxide "in.

"oe the roaster are the oxide start up "in and the fine oxide "in. 'he roster is filled with oxide out

of these "ins."sorption 8ownstream of the preconcentrator% the cooled roast gas enters the

a"sorption column. !ere the roast gas is intermixed with rinse water. :ithdrawn from the "ottom of

the a"sorption column regenerated acid is led " a"sorption transfer pumps to the tan$ farm. !Cl of

the roast gas is a"sor"ed into the liquid and allows producing a +19 to +39 hdrochloric acid%

proided the correct ratio "etween roast gas and rinse-water is applied.

'he safet column is fed with rinse water which is led to the "ottom of the column and circulated tothe top and to the top of the a"sorption column.

%.+ ,x*aust gas cleaning

'he exhaust gas is drawn through the plant " a speed controlled exhaust gas fan which controls

negatie pressure in the roast gas pipe. 'hus neither fugitie gases nor dust can escape to the

enironment. s the fan is spraed with water to preent it from corrosion and further aerosol

remoal% a droplet separator is installed "ehind the fan and the wash water which is collected on

the "ottom off the droplet separator is directed to the safet column.

fter the droplet separator the exhaust gas enters a enturi scru""er charged with industrial water

from the final scru""er which is circulated to the throat. !Cl and dust are remoed here " thewater spra. 'he liquid drops are separated from the gas in a flooded el"ow. 6efore the exhaust gas

leaes the process ia the stac$ to the atmosphere it passes a final scru""er where the gas again is

"rought into contact with industrial water.

%.- an$ "arm

Connected to the regeneration plant is the tan$ farm% in which the liquids from and to regeneration

can "e stored. 'he tan$ farm is also connected to the pic$ling line% to receie waste acid and rinse

water from the pic$ling line.

dditionall inside the tan$farm there is a fresh acid loading from the fresh acid wagon.

'he fumes from the tan$ farm are cleaned in the tan$ fume scru""er and transported to the final

scru""er.


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Process Description

%./ an$ "arm Capacit'

Rinse :ater ; +5* F,

:aste Pic$le ,iquor ; 0* F,

Regenerates cid ; +5* F,

7resh cid ; +5* F,

6S, cid Regeneration Plant 2 Schematic 8iagram

Regenerated

Acid

Waste

Acid

Rinse

Water

Fresh

Acid

Waste

Acid


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Process Description

6S, cid Regeneration Plant -- 'an$ 7arm rea

+.Cold Rolling!

'he primar function of Cold Rolling is to reduce the thic$ness of !ot Rolled Pic$led strip

at room temperature. 8uring the operation oerall max reduction of upto 3 9 in thic$ness

of the !R Coil can "e achieed.'he reduction in the thic$ness of !R Coil is achieed " passing the steel strip at room

temperature "etween a pair of rolls (called wor$ rolls) which are made of induction

hardened special allo steels% under hea rolling force "eing applied from top and "ottom

sides of the rolls with the help of hdraulic sstem and tension "etween the entr reel and

delier reel of mill.

Eer time the strip passes through the wor$ rolls of CR mill% it is referred to as a GPassH

and on an aerage during each GPassH there is a reduction of "etween +-4*9 in the

thic$ness of steel strip.

'he "road specifications of the 10#0 mm /H mill are listed "elow

+ Strip width range ** 2 +** mm

Strip thic$ness range +.4 2 4. mm (#ncoming)

*.+4 2 .* mm (Outgoing)

0 Mill Speed * 2 4* 2 +** mpm

4 #MR shifting B/- 4* mm

Roll separating force +** tons

Regenerated

Acid

Waste

Acid

Rinse

Water

Fresh

Acid

Waste

Acid


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Process Description

5 Coiler tensions +**** $g max. upto A5* mpm

1 Coiler tensions 3*** $g max upto +** mpm.

'he "road specifications of the 1#-0 mm /H mill are listed "elow

+ Strip width range 5* 2 +* mm

Strip thic$ness range +.4 2 4. mm (#ncoming)

*.+4 2 .* mm (Outgoing)

0 Mill Speed * 2 4* 2 +4** mpm

4 #MR shifting B/- 4* mm Roll separating force +** tons

5 Coiler tensions +*** $g max. upto A5* mpm

5 Coiler tensions A5** $g max upto +** mpm.

/ H M H&23G H, 4OO53G 4,&6R,!

+ Iniersal Crown Control Mill - 5 !i Mill i.e. perfect flat wor$ roll% there is no

concae are conex crown in the wor$ rolls.

Mass flow%automatic gauge control

0 'he a"oe mill speciall design to roll thinner gauge in fie passes.

4 On line Jamma ra thic$ness gauge for measurement of thic$ness of sheet.

Mill master control comprises of normal operation% quic$ stoc$% emergenc stoc$%

corner rounding% mill idle run% reision of mill roll dia meter% rolling direction%

reduction ratio (draft) setting% reel stall tension% treatment of coil width%

mechanical loss compensation% control at the time of strip "rea$age% mill speed

reference% reel control

5 utomatic slow down% utomatic intermediate slow down% automatic tail end

stop% utomatic speed slow down Control% automatic deceleration control

1 Elongation Control

3 Operation mode% consist of rolling mode and roll change mode

A Emergenc dnamic "ra$ing sstem

+* uto strip centering deice

++ Mill management sstem

+ CC'K camera sstem is proide for good superision of the operation of mill

+0 Computeri&ation leel-##% comprises of mill set up.


8/26


Process Description

-.Re7inding 8 rimming ine

8uring the process of cold rolling the edges of the strips are crac$ed which need to "e trimmed

"efore further processing. 'herefore% 6S, proposes to set up a trimming line with a facilit for re-

winding of the coil after trimming.

Parameter peci"ications

,ine speed *-**-** mpm

r"our dia meter +** MMStrips width range ** 2+*mm

Strip thic$ness range *.+ to .** mm

Max Coil weight 3.1 ton

/. Galvanizing!

'he Cold Rolled sheet in their raw phsical form is ulnera"le to rusting and corrosion. 'opreent this the CR sheets are coated with a thin laer of Linc ie% galani&ing.

(i) 3on9Ox Galvanizing:Galume ine

7or Jalanising the sheet is first degreased with the help of al$ali in the degreasing section.

'hen the strip is heated in oxgen free enironment (called non-ox &one of the ,ine)

through Open firing. 'he temperature in this &one is upto 4* 8eg. C. 'hen the strips moes

into another heating section where the strip is further heated indirectl through radiant tu"es

(the &one is called R'7). fter this the strip moes into soa$ing section where the striptemperature is maintained at a constant leel. 'hen the strip moes into cooling section

where the temperature is "rought down to &inc "ath temp leel. 'he entire process imparts

annealing properties to the strip. 'he part of the process is optional so that in case the strip is

desired to "e full hard the annealing process is not done.

fter this% the CR coil is passed through a Linc "ath% which is heated upto a temperature of 4* deg

C. 'he duration for which the CR coil is $ept in the "ath is er meticulousl controlled to ensure

consistent qualit of the finished product. :ith the "ath/ dip a thin laer of Linc gets deposited on


9/26


Process Description

"oth sides of the coil. On an aerage% the CR coil gets a coating of a"out *.*0 mm thic$ness on each

side.

Jalani&ing is a Process of Linc / luminium coating on CR sheet. CR Coil after rolling is to "e

passed through de grea&e Section and then through Don Ox. 7urnace and then through molten

Linc/luminium Pot. fter coating sheet will "e passed through water quenching and then Chromic

acid /crlic Coating will "e applied and then coiled.

'he list of maor equipments for Don-ON Jalanising ,ine with l$ali Cleaning% 6S, will

put up are as mentioned hereunder ;-

(C) ,ntr' ection ;

+ 'wo nos. coil storage saddles

'wo nos. entr coil cars

0 'wo nos. uncoilers with roll centering

4 Peeler ta"le

Pinch roll

5 'wo nos. entr crop shears

1 8eflector roll3 Scrap "ox with ta"le

A Seam welder

+* :eld hole punch

++ Carr oer ta"le

+ 'ension "ridle

+0 Steering sstem

(6) Degreasing section 9

+4 'wo nos. l$ali cleaning tan$s with al$ali spras and "rush scru""er

+ !ot water rinse tan$

+5 8rer

+1 7ume exhaust sstem

+3 Entr accumulator (ertical tpe)

+A Steering unit

* 'ension "ridle

+ 'ension-meter rolls


10/26


Process Description

(C) 4urnace ection 9

Don-Ox 7urnace

- non ox section

- radiant tu"e heating section

- soa$ing section

- et cooling section

- turn down roll section

- control instruments

0 Jalanising pot with pot furnace

(D) Galvanising ,


11/26


Process Description

45 Recoiler with pusher plate

41 6elt wrapper

43 Exit coil car

4A Coil storage saddle for two coils

Ceramic Pots!Don Ox galani&ing shall "e equipped with Ceramic #nduction pots for

ax %IS for melting of Linc% Linc-luminum

'here are 0 nos. of #nduction pots are used one for Linc onl % one forLn-l allo and one as premelt pot.

(ii) 4lux Galvanizing ine

7or Jalanising the sheet is first degreased with the help of al$ali in the degreasing section

and then passed through light acid for remoal of an oxides.'he strip then enters preheater

where it is heated to +3* 2 ** oC "efore it is dipped inside the &inc pot.

fter this% the CR coil is passed through a laer of ( D!4Cl B DaCl )flux "ath% which is

maintained a"oe the lead "ath. 'he 7lux "ath

finall cleans of an oxides "efore it enters the molten Linc at temperature of 4* deg C.

'he duration for which the CR coil is

$ept in the "ath is er meticulousl controlled to ensure consistent qualit of the finished

product. :ith the "ath/ dip a thin laer of Linc gets deposited on "oth sides of the coil. On

an aerage% the CR coil gets a coating of a"out *.*0 mm thic$ness on each side.

'he list of Maor equipments for 7lux Jalanising ,ine with l$ali Cleaning% 6S, will put

up are as mentioned hereunder ;-

(&) ,ntr' ection ;

+ 'wo nos. coil storage saddles


12/26


Process Description

'wo nos. entr coil cars

0 'wo nos. uncoilers with roll centering

4 Peeler ta"le

Pinch roll

5 'wo nos. entr crop shears

1 8eflector roll

3 Scrap "ox with ta"le

A Seam welder

+* :eld hole punch

++ Carr oer ta"le

+ 'ension "ridle+0 Steering sstem

() Degreasing section 9

+4 'wo nos. l$ali cleaning tan$s with al$ali spras and "rush scru""er

+ !ot water rinse tan$

+5 8rer

+1 7ume exhaust sstem

+3 Entr accumulator (ertical tpe)+A Steering unit

* 'ension "ridle

+ 'ension-meter rolls

(C) &cid section 9

One no. cid Cleaning tan$s

0 Cold water rinse tan$

4 7ume exhaust sstem

(D) trip Pre Heater and 4urnace ection 9

!ori&ontal gas heated Strip Preheater

5 Jalanising pot with pot furnace

(,) Galvanising ,


13/26


Process Description

Sin$ roll assem"l

- 8eflector roll assem"l

- :iper roll assem"l

- et no&&les pair

- et "lower

- et no&&le controls

- Linc "ox and SS flux 6ox

-7lux 7ume Exhaust Sstem

- Ln/ l 7eeding "as$et and llo :eir

3 8eflector roll no. with snu""er roll and motor

A Cooling tower with cooling pendants and "lowers0* :ater quench tan$ with squee&e rolls and accessories

0+ 'ension "ridle

0 S$in pass mill 4 !# tpe

00 'ension "ridle

04 'ension leeller unit

0 'ension "ridle

(,) C*romating and ,xit ection 905 Chromating tan$

01 7ume exhaust sstem

03 !ot air drer

0A 6randing machine

4* 8eflector roll

4+ Steering sstem

4 Exit accumulator ertical tpe with hdraulic controls

40 :eld hole detector 44 Exit shear

4 Pinch roll

45 Steering sstem

41 Carroer ta"le

43 Recoiler threading apron

4A Recoiler with pusher plate

* Sleee feeding arrangement

+ 6elt wrapper


14/26


Process Description

Exit coil car

0 Coil storage saddle for two coils

=. Cut to engt*(C) lines (4OR GP)

6S, has nos. high capacit Cut to ,ength lines to cut galani&ed coils into sheets . 'he

emphasis of JP Strip processing has totall shifted during the past man ears towards high

qualit scratch or mar$ free material% more so in the case of cut sheet. 7urther% modern

manufacturing techniques demand a er high degree of flatness in the cut sheets "esides

"eing free from mar$s. 'he present mar$et also demands sheets cut to fairl accurate lengths

thus demanding incorporation of sophisticated electronic length measuring sstem.

'his necessitates equipment which must not introduce an mar$s whatsoeer during

processing. 'o meet the er high degree of flatness requirement a precision "ac$ed up

eleen roll straightener is proposed at the entr side followed " a precision seenteen roll

sheet leeler at the exit. 'o ena"le production of mar$ free sheets a fling die shear is

proposed. lthough this equipment is marginall more expensie than the stationar shear

incorporated in start stop lines no mar$ is generated from the feed rolls. 'o cater to the

stringent length accurac requirement the latest and most sophisticated electronic sstem is

installed.

com"ination air float/drop stic$er has "een installed to ensure no mar$s on the sheets are

introduced in this area.

roller ta"le tpe side discharge unit is proposed for automatic remoal of sheet pile from

the stac$er and proiding a suita"le pac$ing station.

'he list of maor equipments for Cut 'o ,ength ,ine% 6S, will put-up are as mentioned

hereunder ;-

+ Coil storage saddle

7loor Mounted Scissor tpe coil car with Saddle

0 Single mandrel uncoiler

4 Coil opener

7ie high leeler with pinch roll and Sunda roll


15/26


Process Description

5 ,oop pit accessories

1 7eed roll with measuring roll unit

3 !draulic shear

A ir stac$er

+* utomatic length cutting sstem

'he "road specifications of this line are as "elow -

+ ,ine speed +* 2 ++* mpm

Strip thic$ness range *.+0 2 *.1* mm

0 Strip width range 5** - +* mm4 Cut length +*** - 0*** mm

Max no of cuts * per minute

5 Stac$ weight *** $g max

1 Stac$ height ** mm max

3 Stac$ height B/- *.0 mm

A 8iagonal accurac B/- *.3 mm

>.,nd traig*tning 8 Cutting lines "or ,nds

'his line used for leelling cutting for off gauge leader ends% :hich is "eing produced

during cold rolling .

'he list of maor equipments for this ,ine% 6S, will put up are as mentioned hereunder ;-

+ Shaft stands for small coils

Incoiler

0 Roller 'a"le

4 Side Juide

Pinch roll cum ,eeller

5 !draulic Crop Shear 1 Jauge ta"le

3 !draulics Electricals

'he "road specifications of this line are as "elow 2

+ ,ine speed + mpm

Strip thic$ness range *.++ - 5.** mm

0 Strip width range ** - +* mm

4 Cut length 0*** mm

Max no of cuts per minute

5 Cut length accurac B/- .* mm


16/26


Process Description

?. P s*eet "urnace!6P sheet furnace is used for annealing of CR sheets which are generated from

Mill Scrap/6a" Coils.'here are a total of + a"ses and 5 heating furnaces in the plant.CR after

receiing from C', used "e load in 6P furnace as per width length of the sheet on "ases.fter

that heating furnace is to "e put on the "ase and heating of the "ase will "e started.7ollowing is the

heating/nnealing ccle for 6P Sheet.

10.

Corrugation Mac*ines!

#n case the finished product requirement is in the form of Corrugated Sheets% the sheets are

fed into a corrugation machine and the plain sheets are conerted with the help of the

rotating rollers into Corrugated sheets.

Description

Corrugating Machine is used for corrugating galanised sheets as per #S# and #S standards

i.e. ++/+ crests for A** mm strip width.

Our Corrugating Machine comprises of;

Jear 6ox with gear ratio 0* ; +.

.C. Motor of power $:% +** rpm.

Annealing cycle for BP sheet

18 hr 2 hr

Total 78 Hrs 4 hr 6 hr 24 hr 24 hr

Time (Hours)

Temperature0C

6500C

5500C

3500C


17/26


Process Description

Corrugating Machine is drien " an .C.Motor through a full geared coupling%

worm Jear 6ox% half gear coupling and then through the gear pair to "ottom

corrugating roll.

7lattening roll is drien " a Chain Sproc$et drie arrangement through the

Corrugating Roll.

n Entr 'a"le is proided with machined slots on either sides to facilitate sliding of

the Sliding 7rame with a Roller arrangement.

'he moement of the Sliding 7rame is achieed " the Cran$% dusting 6loc$

,in$s. 'he Cran$ is mounted on the 6ottom Corrugating Roll.

Stopper 6loc$ is proided for adusting the length of the strip to "e Corrugated.

7or these adustments Measuring Scales are proided on the Sliding 7rame.

n Entr Juide Plate is placed in "etween the Entr 'a"le and the !ousing% for

proiding the entr of sheet into the Corrugating Rolls along the Pass- ,ine.

n uxiliar 'a"le is placed "etween the Corrugating Ross ss. and the Pinch Roll

ss.% for the proper entr of the Corrugated Sheet/s into the Pinch Roll ss.

n Exit ta"le is proided for remoing the finished Corrugated sheets.

Screw 8own is for increasing / decreasing the num"er of crests formed on the sheets.

actuator is proided for adusting the gap "etween the 7lattening Roll ss.% for

maintaining the proper flatness on the crests of the corrugated sheets.

'he "road specifications of this line are as "elow 2

,ength of the sheet 01** mm max.

:idth of the sheet 15 mm to +* mm.

'hic$ness range of sheet *.+ mm upto *. full hard onl.

Material to "e corrugated Jalanised sheets.

8rie FwQ +** rpm CQ 0 Phase.

Space requirement 5 mtr. x 5 mtr.

Do. of corrugator teeth 4 teeth.

Outer 8iameter of Corrugator Rolls 03+ mm.

8iameter of 7lattening Rolls 0+1 mm.


18/26


Process Description

6arrel ,ength 03** mm.

Speed +-+3 sheets per minute approx.

'he list of maor equipments for Corrugation ,ine% 6S, will put up are as mentioned

hereunder;-

+ !ousing

Corrugating 6ase 7rame

0 Corrugating Rolls

a. 'op

". 6ottom

4 7lattening Rolls ('op 6ottom)

Jears Pinions

Entr Exit 'a"les

1 :orm Jear 6os (+H Si&e% 0*;+)

3 C Motor% Fw 2 +** rpm

A Motor 6ase 7rame

+* Coupling (+*0 +*4

11. Roll Grinding Mac*ine!

8uring rolling of strips rolls surface ma get damaged/spoiled due to arious reasons% some

of which are mentioned hereunder;-

(i) Operational faults % pinching

(ii) #mproper coolant oil suppl(iii) 6ad surface of strips/sheets

(i) 6ad qualit of rolls

() Surface wor$ hardening of rolls

(i) Surface crac$s and surface su" crac$s etc.

'hese results into the strip surface defects li$e Roll mar$s


19/26


Process Description

6S, proposed to install :aldrich Siegen Roll Jrinding Machine along with E88

Current 'ester% Iltrasonic 'esting Machine% 8emagneti&ed Init Cali"ration Init in the

Roll Jrinding Shop. 'he proposed shop shall "e among the most sophisticated roll grinding

shops in the world.

'he list of maor equipments for this Roll Jrinder is as mentioned hereunder;-

+ :or$piece "ed. Carriage "ed

0 !eadstoc$

4 'ailstoc$ with mounted dressing unit

Coolant pumps with mounted motor and strainer

5 Prism for chec$ing the alignment of the "ed.

1 Mandrel for chec$ing the alignment of the "ed.

3 Mandrel for chec$ing the alignment "etween headstoc$ and tailstoc$

A Jrinding wheel holder

+* Puller and lifting deice for grinding wheel holder

++ 8ressing unit at tailstoc$ suited for acceptance of demand

'echnical data -

+ Range of roll dia to "e ground ** - +** mm

Oerall grinda"le length of roll 4 mtr.

0 Max grinda"le roll weight 0 tons

4 Jrinding wheel dia A+ mm

'he Roll grinding machine haing the following main features ;

+. Jrinding carriage with CDC control and cam"ering deice

. !drodnamic stead rest for wor$ roll and "ac$ up rolls

0. CDC control sstem JPC including programme for wheel dressing% wheel diameter

is measured in directl after wheel dressing.

4. Measuring "eam for measuring scales for axes N%L and I

. 8irect indication% regulation and control of the cutting speed


20/26


Process Description

5. utomatic grinding wheel retraction incase of power failure or emergenc.

'his Roll Jrinder has got the latest technolog aaila"le in the world with full automatic CDC

Operational Control to ena"le to get the "est of the accurac which are mentioned "elow -

#. Roundness *.**+- *.** mm

ii. Straightness of the generating *.**+- *.** mm

line

iii. Cam"ering accurac B/-*.** mm/M on *.+ mm

Reground rolls ma under go for surface inspections with help of Edd Current

'esters and Iltrasonic 'esting for Su"-Surface #nspection.

process desc 1

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