a5-4 applying fuel gas welding

7/26/2019 A5-4 Applying Fuel Gas Welding

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Applying Fuel Gas Welding

(FGW)

Processes and Techniques


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Next Generation/Common Core tandards Addressed!

CC"#$A$iteracy"%T"& '"' Cite speciic textual e*idence to support analysis

o science and technical texts+ attending to the precise details o explanations or

descriptions"

CC"#$A$iteracy"%T"& '", Follo- precisely a complex multistep procedure

-hen carrying out experiments+ ta.ing measurements+ or perorming technical

tas.s+ attending to special cases or exceptions deined in the text

CC"#$A$iteracy"%T"'' 'Follo- precisely a complex multistep procedure

-hen carrying out experiments+ ta.ing measurements+ or perorming technical

tas.s analy0e the speciic results 1ased on explanations in the text2",


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3ell Wor. !

#xplain theundamentals o uel

gas -elding"

#xplain ho- to selectuel gas -elding

equipment and

supplies"

4escri1e ho- to set5upuel gas -elding

equipment"

#xplain ho- to operateuel gas -elding

equipment"

4escri1e uel gas-elding techniques"

6dentiy saety practices

that should 1e

o1ser*ed in uel gas-elding"


4/144

6nterest Approach

7ere is an arc -elder and uel gas-elder exhi1ited side 1y side"

What is the dierence 1et-eenthem8

The dierences are not only

physical in appearance+ 1ut also in

the heat generated and processes

that can 1e completed -ith each"


5/144

Terms

Acetylene

3lo-pipe

Car1uri0ing lame

Flash1ac.

Flash arrestors

Neutral lame

9xidi0ing lame

9xygen

%egulator


6/144

What are the undamentals o

uel gas -elding8


7/144

9xy5uel -elding is a process 1y

-hich t-o pieces o metal are

:oined together" Acetylene is the

most common uel gas+ 1ut

propane and ;APP gas may 1eused! Acetylene is the preerred

uel gas or -elding"


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9xyacetylene -elding

This process is 1uilt upon t-oundamental principles"

'" Acetylene 1urned -ith oxygenproduces a lame so intensely hot

that it can 1e used to melt and use

metals"


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9xyacetylene Cutting

2" A stream o oxygen directedagainst a piece o iron or steel+

-hich has 1een heated to its.indling temperature+ causes the

metal to 1urn a-ay so that it can 1e

used to cut or shape the metal asdesired"


10/144

#ach o the uel gases ha*e

ad*antages and limitations"


11/144

Acetylene (C27

2)

Acetylene is a uel gas made ocar1on and hydrogen+ and is

produced rom the chemicalreaction 1et-een calcium car1ide

and -ater"

Acetylene is colorless+ 1ut it has adistinct odor"


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AcetyleneThe acetylene lame produces a theoretical

temperature o ?=F"

Acetylene is stored in a ree state under amaximum pressure o'> psi"

Acetylene is *ery unsta1le! 6t can 1e madeto 1rea. do-n 1y heat or shoc. and

explode"


13/144

The results o storing/handling/transporting

acetylene improperly!


14/144

Proper transportation o Acetylene!

Cylinders shouldremain upright to a*oid

pressure changes"

Cylinders should not 1e

laid o*er at more than

a @> degree angle"

6 a cylinder is laid

do-n it should 1e gi*en2@ hrs" to stand upright

1eore use"


15/144

Acetylene

nder a pressure o 2&"@ psi+ orgreater it 1ecomes sel5explosi*e

and the slightest shoc. -ill set it o"

Acetylene+ -hen dissol*ed in

acetone+ can 1e compressed into

cylinders at pressures up to 2> psi"


16/144

Acetylene

The acetylene cylinder is illed -ithporous materials such as 1alsa

-ood+ charcoal+ shredded as1estos+organic pith+ or Portland cement" These materials are used to decrease

the si0e o the open spaces in thecylinder"


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Acetylene

Acetone+ a colorless+ lamma1leliquid+ is added until a1out @

percent o the porous material isilled"

The iller material acts as a sponge

and a1sor1s the acetone+ -hich inturn a1sor1s the acetylene"


18/144

Acetylene

The acetylene cylinder is equipped-ith saety plugs -ith a lo-5melting

alloy center that melts at 2'2=F"7oles are too small to permit a

lame to 1urn 1ac. into the cylinder+

should the escaping acetylene1ecome ignited"


19/144

;APP

;APP+ methylacetylenepropadiene+ is a sta1ili0ed

methylacetylene" A gas reining 1yproduct" (requires special torch tips)

6t com1ines the high energy

characteristics o acetylene -ith thehandling and storage eatures o

liqueied petroleum gases"


20/144

;APP

C,7@has a lame temperature o>,=F"

The 1ushy lame ma.es -eldingdiicult -ith ;APP gas"


21/144

Propane

Propane+ C,7?+ has a maximum

lame temperature o >,=F" (Again

it requires a dierent torch tip")

The *olume o oxygen required to

de*elop the >,=F produces anoxidi0ing lame that is unaccepta1le

or -elding iron and steel"


22/144

The oxygen used in the

oxyacetylene process is

manuactured rom liquid airand stored in hollo- steel

cylinders"


23/144

9xygen

9xygen is a tasteless+ colorless+odorless gas that is slightly hea*ier

than air+ and is nonlamma1le"

When com1ined -ith other

elements+ it -ill support com1ustion"


24/144

9xygen

Commercial oxygen is supplied tousers in seamless steel cylinders

that are charged -ith oxygen to a

pressure o a1out 22 psi at B=F"

The pressure -ill increase and

decrease as the temperature

changes"


25/144

9xygen

The oxygen cylinder has a *al*e made oto1in 1ron0e"( 3ron0e -ill not produce spar.s)

ince 1ron0e is sot+ protection must 1e

pro*ided to pre*ent it rom 1eing 1ro.en or.noc.ed o"

uch protection is pro*ided 1y a steel cap

that is threaded to the top o the cylinderthat co*ers the *al*e during transportation

and storage"


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9xygen

The oxygen cylinder *al*e has adou1le5seat+ the second seat

ser*ing to pre*ent lea.age around

the *al*e stem and the *al*e -hen

it is ully opened"


27/144

7o- are uel gas

-elding equipment

and suppliesselected8


28/144

Purchase equipment o good

quality rom a relia1le dealer-ho -ill gi*e you ser*ice"


29/144

There are se*eral pieces o

equipment and proceduresnecessary or sae uel gas

-elding"


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Welding #quipment

e*eral si0es o cylinders area*aila1le or use in uel gas -elding"

$arge cylinders hold 2@@ cu" t"+medium cylinders hold '22 cu" t"+ and

small cylinders hold only ? cu" t" o

oxygen" Common acetylene cylinders ha*e

*olumes o '2> to 2> cu" t"


31/144

Welding #quipment

9xygen and acetylene ittings arenot interchangea1le"

9xygen ittings ha*e right5handedthreads

Acetylene ittings ha*e either let5

handed threads or a smaller si0e

right5hand connection"


32/144

Acetylene

Fittings

Acetylene torchand hose ittings

al-ays ha*e a

groo*e machined

into the middle o

the itting as a

reminder that the

threads arere*ersed"


33/144

Welding #quipment

There is a regulator attached to eacho the tan. *al*es"

The regulator is a de*ice used to

*ary line pressure on a tan." #ach regulator has a diaphragm

ad:usting scre- to *ary the linepressure+ and has t-o gauges one

sho-ing cylinder pressure and one

sho-ing line pressure"


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35/144

Welding #quipment

The hoses used are colored onegreen and one red"

The green hose is used or oxygenand has ittings -ith right5hand

threads"

The red hose is used or the uel gasand has let5handed ittings"


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Welding #quipment

The hoses connect the 1lo-pipe to the regulators"The 1lo-pipe is a mixing cham1er"

The t-o gases are mixed and deli*ered to the tip

ready to 1urn" The 1lo-pipe has a *al*e to control the oxygen

and one to control the acetylene"


38/144

Torch Blow pipes Welding tip assortment


39/144

Welding #quipment

There are dierent tips that areattached to the 1lo-pipe to perorm

dierent tas.s"

A -elding tip is used or -eldingpieces together and a cutting

attachment -ith a tip is used to cut

metal" pecial tips are a*aila1le to perorm

other tas.s such as heating"


40/144

Welding #quipment

Welding goggles or ace shields+ ilter outultra*iolet and inrared rays and protect the

operatorDs eyes"

A No" > lens is satisactory or light5dutyoxy5uel gas -elding"

A riction lighter should 1e utili0ed to light the

1lo-pipe"


41/144

Welding #quipment

Gauntlet glo*es+ made o leather+as1estos+ or other material that

does not 1urn readily+ should 1e

-orn -hen -elding or cutting"

3e sure the glo*es are ree rom oil

or grease 1ecause such materialsare dangerous -hen in contact -ith

oxyacetylene equipment"


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Welding #quipmentThe cylinders should 1e chained in an upright

position -hen used and stored"

The saety caps should not 1e remo*ed until

the cylinders are secured"

9xy5uel gas cylinders should 1e equipped

-ith 1oth re*erse lo- chec. *al*es and

lash arrestors"

Chec. *al*e annually 1y

simply 1lo-ing through them

opposite o the gas lo-!


43/144

Welding #quipment

A lash1ac. is a ire inside the1lo-pipe"

When a lash1ac. occurs in anoxyacetylene unit+ lame physically

tra*els up the -elding tip and

through one or 1oth o the hoses tothe regulator"


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46/144

7o- is uel

gas -elding

equipmentset5up or

use8


47/144

Follo-ing proper procedures-hen setting5up the uel gas

-elding equipment -ill insurethat there are no gas lea.s

and accidents can 1e a*oided"


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General procedures are asollo-s


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Fuel Gas Welding #qt" et5p

Place the cylinders in a cart and asten themtogether -ith a chain or asten the cylinders in

some other manner to pre*ent them rom 1eing

tipped o*er -hile in storage or use"

6 an acetylene cylinder is tipped on its side+ it

should 1e set upright or at least , minutes

1eore 1eing used"


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All cylinders ha*e iron caps toprotect the cylinder *al*es" %emo*e the caps and stand to one side so

you are not directly in line -ith tan. *al*e"

ECrac. the cylinder *al*es slightly+ then+

close them quic.ly"

This -ill 1lo- out all dust and other oreign

matter"


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Connect the acetylene regulator tothe acetylene cylinder and theoxygen regulator to the oxygen

tan."6t should not 1e possi1le to

interchange the regulators"

To a*oid conusion+ the regulator-ith the larger num1ers 1elongs on

the oxygen tan."


52/144


Connect one end o the green hoseto the outlet connection on the

oxygen regulator and the other end

to the oxygen connection on the

1lo-pipe"


53/144


3e sure the lash arrestor isattached to the regulator+( not on

the 1lo-pipe) and the hose is

attached to the arrestor"

6 the unit does not ha*e a 1uilt5inchec. *al*e+ 1e sure one is put

1et-een the hose and the 1lo-pipe"


54/144


Connect one end o the red hose tothe outlet connection on the

acetylene regulator and the other

end to the acetylene connection on

the 1lo-pipe"


55/144


3e sure the lash arrestor isattached to the regulator+ and the

hose is attached to the arrestor"

6 the unit does not ha*e a 1uilt5in

chec. *al*e+ 1e sure one is put1et-een the hose and the 1lo-pipe"


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Close 1oth regulator *al*es 1yturning the regulator diaphragm

scre- countercloc.-ise until the

scre- is loose"(relie*es pressure)

Al-ays close the regulator *al*es

1eore opening the cylinder *al*esto pre*ent the tan. pressure rom

damaging the regulator"


57/144


tanding to one side+ not directly in ronto the regulator+ open the acetylene *al*e

slo-ly"

This *al*e should never be opened morethan one turn so that it can 1e shut o

quic.ly"

6 using uel cylinders that require a T

-rench or opening/closing+ ma.e sure

that the torch is near 1y"


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9pen the oxygen *al*e on the1lo-pipe a1out one5eighth o a turn"

Turn the scre- on the oxygenregulator cloc.-ise until the desired

pressure is reached on the oxygen

lo- pressure gauge"Close the oxygen *al*e on the

1lo-pipe


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9pen the acetylene *al*e on the1lo-pipe a1out one5eighth o a turn"

Turn the scre- on the acetyleneregulator cloc.-ise until the desired

pressure is reached on the

acetylene lo- pressure gauge"Close the acetylene *al*e on the

1lo-pipe"

Fuel Gas Welding #qt et p


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Test or lea.age 1y applying soapy-ater around the *al*es andconnections"

6 a 1u11le appears at a *al*e orconnection+ a lea. has 1eendetected"

6t should 1e corrected 1eore usingthe equipment"

3e sure to use a grease5ree soap"


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7o- is uel gas -elding

equipment operated8


62/144

The correct lighting and

shutting do-n proceduresshould 1e ollo-ed at all

times"


63/144

The ollo-ing is the correctlighting procedure"


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$ighting Procedure

'" Place goggles or saety glassesand ace shield on your orehead"

2" 3e sure regulator ad:usting

scre-s are turned out" The scre- should turn reely"

$ighting Proced re


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$ighting Procedure

," tanding to one side+ not directly in

ront o the regulator+ open the

oxygen cylinder *al*e slo-ly+ then

open it all the -ay" et the regulator at the correct -or.ing

pressure" (turn ad:usting scre- cloc.-ise)

9pen the oxygen 1lo-pipe *al*e andine tune the operating pressure"

Close the oxygen 1lo-pipe *al*e"


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$ighting Procedure

@" tanding to one side+ not directly inront o the regulator+ open the

acetylene cylinder *al*e slo-ly" 9nly open the tan. *al*e to H o a turn" et the regulator at the correct -or.ing

pressure" ( turn the ad:usting scre- cloc.-ise)

9pen the acetylene 1lo-pipe *al*e and ine

tune the operating pressure"

Close the acetylene 1lo-pipe *al*e"


67/144

$ighting Procedure

>" Put on glo*es+ and lo-er gogglesor ace shield o*er eyes"


68/144

$ighting Procedure


69/144

$ighting Procedure

B" Ad:ust the acetylene 1y openingthe 1lo-pipe *al*e until the lame

lea*es the tip a1out I inch" Close the *al*e *ery slo-ly until the

lame is pulled 1ac. to the end o the tip"

9pen the *al*e slo-ly again+ stopping

:ust 1eore the lame lea*es the tip" This is the proper ad:ustment or most

-elding"(1lac. smo.e 1ut no soot)


70/144

$ighting Procedure

?" 9pen oxygen 1lo-pipe *al*e andset the desired lame type"


71/144

The correct shutting do-n

procedure is as ollo-s"

h t 4 P d


72/144

hut 4o-n Procedures

'" Close the acetylene 1lo-pipe*al*e"

2" Close the oxygen 1lo-pipe *al*e"," Close acetylene tan. *al*e"

@" Close oxygen tan. *al*e"

h t 4 P d


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hut 4o-n Procedures

>" 9pen the acetylene 1lo-pipe*al*e to drain the hose and release

all pressure rom the hose and

regulator


74/144

hut 4o-n Procedures

B" Close the acetylene 1lo-pipe*al*e"

?" 9pen the oxygen 1lo-pipe *al*e

to drain the hose and release all

pressure rom the hose andregulator"

h t 4 P d


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hut 4o-n Procedures

&" Turn out the pressure5ad:ustingscre- on the oxygen pressure

regulator 1y turning it counter

cloc.-ise" (loosen+ do not remo*e)

'" Close the oxygen 1lo-pipe

*al*e"''" Wrap up hoses and put -elding

accessories in their proper place"


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What are the uel gas -elding

techniques8

Three types o oxyacetylene


77/144

yp y y

-elding lames"

The neutral lame is usually used

or -elding" A neutral lame -ill

produce a smooth+ shiny 1ead othe 1est quality"

#qual uel/oxygen"



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yp y y-elding lames"

The oxidi0ing lame is caused 1y anexcessi*e amount o oxygen+ -hich

produces a short -hite inner cone

and a short en*elope lame"An oxidi0ing lame -ill produce spar.s that

sho-er the -eld area -ith droplets o

metal and slag+ lea*ing the -eld 0one

-ea. and porous"


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80/144

yp y y

-elding lames"

The car1uri0ing lame is caused 1y

an excessi*e amount o acetylene

and has a long+ 1luish outer lame" A car1uri0ing lame -ill cause the puddle to oam

and 1oil+ lea*ing a 1rittle+ porous+ and scaly -eld

area"

The car1uri0ing lame is used or hard5suracing"


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83/144

When possi1le+ it is desira1le

to prepare 1y cutting+ grinding+iling+ or 1uing a clean+ 1right

surace or -elding 1ecausesuch suraces -eld more

easily than dirty or oxidi0ed

suraces"


84/144

All rust and scale should 1e

careully remo*ed 1eore-elding+ 1ecause such

impurities ha*e a tendency to-ea.en a -eld"

Cutting ;etal or Welding


85/144


The edges o metals o*er '/? inchshould 1e cut to orm a J+ (1e*el) -ith

approximately a @>5degree angle to

permit the complete usion o the t-opieces o metal" 6 the pieces are , /? inch or more in

thic.ness+ it is usually desira1le to cut a J1e*el on 1oth the top and 1ottom sides o

the t-o pieces o metal 1eing -elded"



86/144


The edges o metals o*er '/? inchshould 1e placed a1out '/'< inch

apart to pro*ide or the expansion

and contraction o the metals and to

permit the -eld to penetrate deeply+

through the 1ottom+ i possi1le"


87/144

Types o -elded :oints

requently used are the 1utt:oint+ tee :oint+ corner :oint+ lap

:oint and edge :oint"


88/144

The common -eldingpositions are do-nhand+

hori0ontal+ *ertical+ and

o*erhead"The do-nhand -eld is used

most requently and is theeasiest -eld to ma.e"


89/144

The 1lo-pipe is usually held li.e a

hammer or ishing pole -hen theoperator is -elding -hile standing+

and li.e a pencil -hen the operatoris -elding -hile seated"

6t is desira1le or the operator tohold the 1lo-pipe in a comorta1le

-ay

3lo-pipe Position


90/144

3lo-pipe Position

7old the 1lo-pipe so that the tip -ill1e inclined at a @>5degree angle to

the surace to 1e -elded and -ill

point directly along the line o the

-eld"

7old the tip so that the inner coneo the lame is a1out ' /? to ' /'/'< inch

long"


93/144

Puddle strips+ 1eading+ usion-elding and 1ron0e -elding

are the our 1asic types o

-elding"

$earning to 9xyacetylene Weld


94/144


The irst step in learning to -eld-ith oxyacetylene is to learn ho- to

melt the 1ase metal and ho- to

control the molten puddle" tart the lame at the edge o the steel

piece and orm a molten puddle a1outI inch in diameter and a1out '/? inch

rom the edge o the piece o steel"



95/144


%ight5handed people start at theright5edge o the steel piece"

$et5handed persons should start at

the let5hand edge o the metal"

The -idth o the puddle is a1outt-ice the thic.ness o the metal"


96/144

;a.ing a 3ead


97/144

;a.ing a 3ead

For a right5hand person+ hold the-elding rod in the let hand at a @>

degree angle so that the end o the

rod -ill 1e -ithin the outer en*elopeo the lame"

;a.ing a 3ead


98/144

;a.ing a 3ead

;o*e the 1lo-pipe in a circularmotion and dip the rod into the

center o the puddle each time the

lame reaches the 1ac. o the circle"

;a.ing a 3ead


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;a.ing a 3ead

%aise the rod out o the puddleslightly as the lame is passed

to-ard the ront to the puddle+ thus

synchroni0ing the motions o thelame and the rod"

;a.ing a 3ead


100/144

;a.ing a 3ead

;aintain a molten puddle a1out Iinch in diameter and mo*e the rod

and 1lo-pipe slo-ly+ straight ahead

a1out '/'< -ith each o*al motion othe 1lo-pipe"

;a.ing a 3ead


101/144

;a.ing a 3ead

%aise the rod out o the -ay o thelame to permit the lame to heat the

metal ahead o the 1ead"

$o-er the rod so that the lame -illmelt it+ causing the -elding rod to

lo- into the molten puddle" The end o the -elding rod should touch the

puddle on the do-n-ard stro.e"

The rod should not dip into the puddle"

Fusion Weld


102/144

Fusion Weld

A usion -eld is the next step aterlearning to ma.e a 1ead"

T-o pieces o metal are -elded

together using a iller rod" elect t-o pieces to 1e -elded and

space them so that the edges o the

metal are ' /'< inch apart at one endand approximately ' /? inch apart atthe other"

Fusion -eld


103/144

Fusion -eld

;a.e a tac. -eld at each end othe pieces to hold them together"

Follo- the same procedure and

motion that -as used in ma.ing a

1ead"


104/144

3ron0e -elding has some

ad*antages o*er usion

-elding"

3ron0e Welding


105/144

3ron0e Welding

ince 1ron0e -elding does notrequire a melting heat+ it can 1e

done aster than usion -elding+

-hich sa*es time and gas"

Considera1ly less expansion and

contraction o parts occurs -ith1ron0e -elding than -ith usion

-elding"

3ron0e Welding


106/144

3ron0e Welding

7eat the 1ase metal to a salmonred color" The 1ron0e rod should not remain in

the inner cone o the lame"

The inner cone o the lame should

not stay in one spot o the molten1ron0e"

The intense heat -ill 1urn the 1ron0e"

3ron0e Welding


107/144

3ron0e Welding

The same technique and mo*ementthat -as used -ith usion -elding

should 1e ollo-ed"


108/144

What saety

practices should

1e o1ser*ed

-hen uel gas-elding8


109/144

3ecause o the intense heat

and other opportunities or

accidents+ saety is o extremeimportance in uel gas

-elding"


110/144

The ollo-ing are some

suggested practices and

tips that -ill help toeliminate shop accidents

-hen uel gas -elding"


111/144

'" To pre*ent oxygen and uel cylinders rom1eing tipped o*er accidentally+ asten them

securely in an upright position -ith a chain orsimilar de*ice 1eore remo*ing the saety cap"

2 K il d


112/144

2" Keep oil and grease a-ay

rom oxygen cylinders andequipment"

9il and grease may catchire or explode

spontaneously in the

presence o oxygenescaping rom the cylinder or

the equipment ," Chec. equipment connections

periodically


113/144

periodically

Chec. -ith a clean paint 1rush andgrease5ree+ soapy -ater to 1e sure

there are no lea.s o oxygen or uel gas"

Test hoses 1y putting them in a pail o-ater and -atching or 1u11les"

Ater ma.ing any ne- connections+ test

equipment immediately"


114/144

@" Chec. regulator gauge

operation pressures careully

and ollo- recommendations"


115/144

>" Clear the area o all

com1usti1le materials 1eore

lighting the torch"

4oing this may a*oid anexplosion or serious ire"


116/144


117/144

o the regulator+ -hen opening the

cylinder *al*e"A deect in the cylinder *al*e may cause the

gas to 1lo- out+ shattering the glass+ and

1lo-ing it into your ace"9pen the *al*e slo-ly"

6 the gas in the tan. is permitted to enter the

regulator suddenly+ it may cause damage to theequipment+ and particularly to the regulator

diaphragm"


118/144

?" 4o not open the 1lo-pipe

*al*es more than turn -henlighting the torch"

&" Ne*er use a match to light


119/144

g

the torch"

sing matches 1rings your ingers

too close to the tip"

The sudden ignition may cause

1urns"

'" Al-ays use a spar. igniter or

i ti li ht t li ht ldi


120/144

riction lighter to light a -elding

torch"

When lighting a torch+ .eep the tip

acing do-n-ard and a-ay romyou"

$ighting the torch -hile it is acingup-ard or out-ard may result in

1urns

''" ;a.e no attempt to relight


121/144

p g

a torch rom hot metal"

The gas does not al-ays ignite

instantly+ and the accumulating gas

may ignite *iolently"

$ight the acetylene irst and addoxygen to the lame"


122/144

'2" 3e sure that other -or.ers

are in the clear 1eore

relighting a torch"

'," 4o not -al. -ith a lighted torch or

l d li ht d t h


123/144

lay do-n a lighted torch"

3e certain the lame is out 1eorelaying do-n the torch"

Ne*er -al. around -ith a lightedtorch"

3eore you light the torch+ get into

position or -elding or cutting andremo*e all o1stacles 1et-een youand the shut5o controls


124/144

'@" 3eore opening a cylinder

*al*e+ 1e sure the regulator

*al*e is closed 1y turning itcountercloc.-ise until it is

loose"

'>" 6 a lash1ac. should occur


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Turn o the torch immediately+close the cylinder *al*es+ and notiy

your instructor"

A lash1ac. has occurred -hen the

lame disappears and 1urns 1ac.

inside your equipment"There is a hissing+ squealing sound"

'>" 6 a lash1ac. should occur


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mo.e may come out the torch tip+ andthe handle may get hot"

6 the torch is not turned o promptly+ ire

may reach the hoses or the cylinder"4o not relight ater a lash1ac. until the

equipment has 1een inspected closely+

and perhaps repaired"

'


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cylinder *al*e more than to H

o a turn"$ea*e the T5handle -rench in

position at all times -hile -elding"Lou should 1e a1le to turn o the

acetylene cylinder *al*e promptly in

case o ire"


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'B" Ne*er do any -elding oncontainers that may ha*e held

lamma1le su1stances"

$ea*e this -or. to proessionals"


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'?" When -elding or cutting

0inc or gal*ani0ed metals+

ma.e a special eort to a*oid1reathing the umes -hich can

ma.e you eel ill"

'&" Ne*er use acetylene at a


130/144

pressure greater than '>

psi"/9xygen @ psiFollo- the manuacturerDs

recommendations or the correctoperating pressures or the

metal 1eing -elded and or the

tip si0e 1eing used"

2" 4o not smo.e or allo-


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anyone else to smo.e near

the oxy5uel gas -elder"

6 uel gas -ere to lea. rom

the unit+ smo.ing couldpro*ide ignition and cause a

ire or an explosion"


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2'" Keep the lame and heat

a-ay rom the cylinder+ hoses+and people"

53e alert or ires at all times"

5se the proper ire extinguisher

or a ire 1lan.et i necessary"


133/144

22" For most oxyacetylene

-elding+ you -ill need a lens-ith shade No" >"


134/144


135/144

2@" Keep cylinders a-ay rom

electric -iring and a-ay rom

the danger o stri.ing an arcon them -ith an electric

-elder"

2>" 9xygen cylinders are


136/144

yg y

equipped -ith a dou1le seating*al*e"

9pen the *al*e all the -ay to

pre*ent oxygen rom escaping

around the *al*e stem"


137/144

2


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Ne*er gas -eld -hile you are -earingpolyester clothing"

9ily or greasy clothing may 1urn quic.ly i

oxygen is ed into them"%agged clothing is li.ely to catch ire"

3ecause spar.s may lodge in cus androlled slee*es+ turn trouser cus do-n and

1utton slee*es at the -rist"

2?" $o- shoes are not

recommended 1ecause


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recommended 1ecause

spar.s or slag may get intothem"

2&" ;a.e certain that re*erse

lo-5chec. *al*es and lash

arrestors are installed on theoxygen and acetylene lines"


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," 3e sure the cylinder

*al*es are closed and the

pressure is relie*ed rom thehoses 1eore you lea*e the

-or. area"


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,'" %emo*e regulators and

replace protecti*e caps 1eore

transporting cylinders"

,2" tore oxygen cylinders

a-ay rom uel gas cylinders"


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,," Ne*er use oxygen as

compressed air to dust

clothing"Clothing saturated -ith pure

oxygen is highly com1usti1le"


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,@" 7andle hot metal -ithpliers or tongs"

4o not lea*e hot metal on the-elding ta1le 1ecause

unsuspecting persons may

touch it and 1e 1urned"

The #nd!


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a5-4 applying fuel gas welding

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