AWS C5.3-00 Carbon Arc Gouging.pdf

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STD-AWS C 5 - 3 - E N G L 2000

W

07842b5 052003b 7 4 T

American Welding Society Inc.YRIGHT American Welding Society, Inc.ensed by Information Handling Services



Key WOïdS

Air

carbon arc, gouging, cutting,

recommended practices

AWS

C5.3:2000

An American National Standard

Approved by

American National Standards Institute

November

21,2000

Recommended Practices for

Air Carbon Arc Goug ing

and

Cutt ing

Supersedes

ANSUAWS

C5.3-91

Prepared by

AWS

C5

Committee on Arc Welding and Cutting

Under the Direction of

AWS Technical Activities Comm ittee

Appro ved by

AWS Board

of

Directors

Abstract

This publication establishes a method of conveyin g to the welder/operator the proper setup and use of air carbon arc

gouging and cutting. Instructions and proced ures are supplied in detail so the weldedoperator can establish the correct

air pressure, am perage, voltage, and techniques.

AmericanWelding Society

550 N.W. L eJeune Road , Miami, Florida

33126




STD-AWS

C 5 . 3 - E N G L 2000 078q2b5 0520038 512

Statement on Use of AWS Am erican Natio nal Standards

All standard s (codes, specifications, recomm ended practices, methods, classifications, and guides) of the American

Welding Society are voluntary c onsen sus standar ds that have been developed

in

accor dance with the rules of the American

National Standards Institute. When AWS standards are either incorporated in, or made part of, documents that are

included in federal or s tate law s and regulations,

or

the regulations of other go vernm ental bodies, their provision s carry

the full legal authority of the statute.

In

such cases, any changes in those AWS standards must be approved by the

governmental body having statutory jurisdiction before they can be come a part of those laws and regulations. In all

cases, these standards carry the full legal authority of the contract or other docum ent that invokes the AWS standards.

Wh ere this contractual re lationship exists, changes in or deviations from requirements of an AWS standard must be by

agreement between the contracting parties.

International Stand ard Book Number:

0-87171-630-5

American Welding Society, 550 N.W. LeJeune Road , Miam i,

FL

33126

O 2001 by Am erican Welding Society. All rights reserved

Printed in the United S tates of A merica

AWS A merican N ational Standards are developed through a consensus standards development process that brings

together volunteers representing varied viewpoints and interests to achieve consensus. While AWS adm inisters

the

process

and establishes rules to promote fairness in

the

development of consensus,

it

does not independently test, evaluate, or

verify

the

accur acy of any information or the soundness of any judgments contained in its standards.

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reliance on this

standard. AWS also makes no guaranty or warranty

as

o the accuracy or completeness of any inform ation published herein.

In issuing and making

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as

appropriate, seek the advic e

of a competent professional in determining the exercise of reason able care in any given circumstances.

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the

issuanc e of new editions. Users shou ld ensure that they have the latest edition.

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of any patent resulting from the use

or

reliance on this standard.

Finally, AWS d oes not monitor, police, o r enforc e complian ce with this standard, nor does it have the power to do so.

Official interp retations of any of the technical requirem ents of this standard may be obtained by sending a request, in writ-

ing, to the Managing Director Technical Services, American Welding Society, 550 N.W. LeJeune Road, Miami, FL 33126

(see Annex C). With regard

to technical

inquiries made c oncer ning AWS standards, oral opinions on AWS standar ds may

be rendered. However,

such

opinion s represent only the personal opinions of the particular individuals giving them. Th ese

individuals do not speak on behalf of AWS, nor do these oral o pinions constitute official or unofficial opinion s or interpre-

tations of AWS. In addition, oral o pinions are informal and should not be used

as

a substitute for an official interpretation.

This standard is subject to revision at any time by the AWS C5 Co mm ittee on Arc Welding and Cutting. It must be re-

viewed every five years and if not revised,

it

must be either reapproved or withdrawn. Co mm ents (recommendations, addi-

tions, or deletions) and any pertinent data that may be of use in improving this standard are required and should be

addre ssed to AWS Headquarters.

Such

com me nts will receive careful consideratio n by the AWS

C5

Committee on Arc

Welding and Cutting and the author of the comm ents will be informed of the Com mittee’s response to the com ments.

Gues ts are invited to attend all meeting s of the AWS C5 Co mm ittee on Arc W elding and Cutting to expr ess their

com-

men ts verbally. Pro cedure s for appeal of an advers e decision concerning all such comm ents are provided in the Rules of

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online:

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STDmAWS

C 5 . 3 - E N G L

2000 m 07842b5 0520039 Li59

Personnel

AWS C5 Committeeon Arc Welding and Cutting

B.

L .

Shultz, Chair

J .

R .

Hannah, 1st Vice Chair

N.

E. Larson, 2nd Vice Cha ir

C.

R. Fassinger, Secretary

*

D. . Arthur

E .

R.

Bohnart

H. A. Chambers

C. Conneliy

D.

. Fink

I .

D. Harris

*R.I:

Hemzacek

C K.Hicken

J.

E. Hinkel

D. . Holiiday

S.

R. Potter

N . A. Sanders

R. L. Strohl

E. G . Yevick

Th e Taylor Winfield Co rp.

Consultant

Consul tant

American Welding Society

J. W. Ha rris- W eb

Welding Education and Consulting

TRW Nelson Stud Welding Division

Consultant

The Lincoln Electric Company

Edison Welding institute

Consultant

Sand ia National Laboratory

The Lincoin Electric Company

Northrop Crumman Corp.

Consultant

Hyperîherm

Weco-Arcair

Weld-Met International Group

AWS Subcommittee on Air Carbon

Arc

Cutting

R L. Strohl, Chair ïbeco-Arcair

C.

R.

Fassinger, Secretary

J .

DeViro

B. L. Shultz

G . Snyder Tri-County Vocational Schools


ESAB W ldg and Cutting Products

The Taylor Winfield Corp.

*Advisor

i i i




STD-AWS

C5.3-ENGL

2000

07842b5

0520040

170 =

Foreword

(Thi s Foreword is not a part of AWS C5.3:2000, Recommended Practices

for

Air Carbon

Arc

Gouging and Cutting,

but is included for information purposes only.)

These recomm ended practices have been prepared by the Subcomm ittee

on

Air Carbon Arc Cutting,

of

the AWS Arc

Welding and Cutting Committee. It is important to recognize that this publication does not present the only possible

conditions for using the air carbon arc cutting process. The data given are presented merely as guides in establishing

operating conditions.

Comments and suggestions for the improvement of this standard are welcome. They should be sent to the Secretary,

AWS

C5

Committee on Arc Welding and Cutting, American Welding Society,

550 N.W.

eJeune Road, Miami,

FL

33 1 6.

iv




~

STD-AUS C5.3-ENGL 2000 078Li2b5 D5200LiL O07

Table

of

Contents

Page No

...

Personnel .................................................................................................................................................................... 111

Foreword......................................................................................................................................................................

iv

List

of

Figures ............................................................................................................................................................. vii

1

General ..................................................................................................................................................................

1

1.1

Scope

.............................................................................................................................................................

1

1.2

Description ....................................................................................................................................................

1

1.3 History

..........................................................................................................................................................

1

List of Tables .............................................................................................................................................................. vi¡

1.4

Applications

..................................................................................................................................................

1

2 Referenced Standards ............................................................................................................................................ 2

3. Fundamentals of the Process

................................................................................................................................. 2

3.1 General .......................................................................................................................................................... 2

3.2

Power Sources

.............................................................................................................................................. 2

3.3

Compressed Air

............................................................................................................................................

2

3.4

Electrodes

...................................................................................................................................................... 2

3.5

Gouging and Cutting Leads

.......................................................................................................................... 4

3.6

Manual Cutting Torches

................................................................................................................................ 4

3.7

Mechanized Cutting Torches ........................................................................................................................

4

3.8

Vacuum Gouging

.......................................................................................................................................... 6

4

.

Operating Techniques

............................................................................................................................................

6

4.1

Gouging

........................................................................................................................................................

6

4.2 Cutting .......................................................................................................................................................... 8

4.3 Washing......................................................................................................................................................... 8

4.4

Beveling

........................................................................................................................................................ 8

5 Equipment Selection

.............................................................................................................................................

5.1

Cutting Torch ................................................................................................................................................

8

5.2 Power Sources

............................................................................................................................................... 8

5.3

Mechanized System s

.................................................................................................................................. 10

6

. Process Variables

................................................................................................................................................. 10

6.1 Introduction

................................................................................................................................................. 10

6.2

Electrode Diameter and Type

......................................................................................................................

10

6.3

Amperage ....................................................................................................................................................

10

6.4 Voltage ........................................................................................................................................................ 10

6.5

Air Pressure and Flow Rate ........................................................................................................................

12

6.6 Travel Speed................................................................................................................................................ 12

6.7

6.8

Base Metals .................................................................................................................................................

12

7

Advantages and Limitations ................................................................................................................................

13

7.1

Advantages

..................................................................................................................................................

13

7.2

Limitations

.................................................................................................................................................. 14

Electrode Push Angle ..................................................................................................................................

12

V

American Welding Society Inc.

Services

YRIGHT American Welding Society, Inc.ensed by Information Handling Services



8

.

9.

10

.

Page No

Troubleshooting .................................................................................................................................................. 14

Safe Practices ...................................................................................................................................................... 14

9.1 Introduction................................................................................................................................................. 14

9.2 Noise

...........................................................................................................................................................

14

9.3

Gases

...........................................................................................................................................................

15

9.4 Radiant Energy............................................................................................................................................ 16

Bibliography........................................................................................................................................................ 16

Annex A-C om mo nly Used Metric Conversion .........................................................................................................

17

Annex B -Sa fer y References....................................................................................................................................... 19

Annex C-G uid elin es or Preparation

of

Technical Inquiries fo r AWS Technical Comm ittees

.................................

21

AWS List of Docume nts

on

Arc Welding and Cutting .................................................................................................

23

vi




STD-AWS

C 5 . 3 - E N G L

2000 m

0 7 8 4 2 b 5

05200 i13

9 8 T m

List

of Tables

Table

1

2

3

4

5

6

7

8

9

10

Page

No.

Recommended Minimum Air Requirements ................................................................................................. 4

Recommended Number and Size of Gouging and Cutting Leads for Various Currents and L engths

...........5

Suggested Current Ranges for Com monly Used Electrode Types and S izes ................................................ 6

Mechanized CAC-A U-Groove Gouging Conditions ..................................................................................

11

Automa tic CAC-A J-Groove Operating Data .............................................................................................. 11

Primary P rocess Variables............................................................................................................................ 12

Gouging Recommendations

.........................................................................................................................

13

Results of Corrosion Testing on Type

304L

Stainless Steel ........................................................................

14

CAC-A Troubleshooting

.............................................................................................................................. 15

Particulate Matter with Possible Significant Fume Concentration

in

the Arc Cutter’s Breathing Zone

......16

List of Figures

Figure Page No.

1

2

3

4

5

6

7

8

9

10

11

P p ic a l Arrangement for the Air Carbon Arc Cutting Process

......................................................................

3

How a Standard CAC-A Torch Works ........................................................................................................... 3

Manual Torch ................................................................................................................................................. 5

Mechanized Cu tting Torch

.............................................................................................................................

6

Flat Position Gouging

....................................................................................................................................

7

Vertical Position Gouging .............................................................................................................................. 7

Horizontal Position Gouging ......................................................................................................................... 7

Overhead Position Gou ging........................................................................................................................... 7

Severing/Piercing with CAC-A ...................................................................................................................... 9

Pad Washing with CAC-A .............................................................................................................................

9

Methods of Beveling with CAC-A............................................................................................................... 10




~~ ~

~

S T D - A W S

C 5 . 3 - E N G L

2000 m 0 7 ô 4 2 b 5 0520044 B L b

AWS C5.3:2000

Recom mended Practices for

Air Carbon Arc Goug ing and Cutting

1. General

1.1

Scope. This pub lication presents the basic concepts

of the air carbon arc cutting (CAC -A)' process to provide

a fundamental understanding of the process and its vari-

ables. I n addition, specific technical data are presented as

a guide in establishin g optimum operation of this process.

This standard makes use of the U.S. Customary Units.

Approximate mathematical equivalents i n the Interna-

tional System of Units

(SI)

are provided for comparison

in parentheses ) or in appropriate columns

in

tables and

figures. Annex A is included to identify metric equivalents

if

the reader requ ires precise conversion information.

Safety and health issues and concerns are beyond the

scope of this standard and, therefore, are not fully ad-

dressed herein. Some safety and health information can

be found

in

Section

9.

Safety and health information is

available from other sources, including, but not limited

to, ANSI 249.1, Safety in W elding, Cutting, and Allied

Processes, and ap plicable federal and state regulations.

1.2

Description.

CAC -A is a physical means of metal

removal in contrast to the oxidation reaction

in

oxyfuel

gas cutting (OFC). In the CAC-A, the intense heat of the

arc between the carbon electrode and the workpiece m elts

a portion of the workpiece. S imultaneously, a jet of air is

passed p arallel to the arc and is of sufficient volume and

velocity to blow away the molten material. The exposed

solid metal is then melted by the heat of the arc, and the

sequence continues.

CAC-A does not depend

on

oxidation to m aintain the

cut, so i t

is

capable of cutting metals that OFC will not

cut .

The process is used successfully

on

carbon steel,

stainless steel, many copper alloys, and cast irons. The

melting rate is a function of current. The metal removal

rate

is

depend ent upon the melting rate and the efficiency

1. CAC-A (Carbon Arc Cutting-Air)

was

formerly AAC (Air

Arc Cutting).

of the air jet i n removing the molten m etal. The air must

be capable of lifting the molten metal out and c lear of the

arc region before resolidification.

1.3 History. CAC-A was developed

in

the

1940s

as an

extension of an existing pr oce ss- car bo n arc cutting.

Faced with the removal,

i n

the flat position, of several

hundred feet of cracked stainless steel weld, a w elding

engineer developed CAC-A. Carbo n arc cutting was used

to remove defective welds and rivet heads, but only

in

the

overhead and vertical positions. The carbon arc m elted

the metal and gravity moved the molten metal out of the

area. It was reasoned that an air jet could provide the force

to remove the metal in the flat position.

A direct current electrode negative (DCEN) carbon a rc

was tried, and an air blast was provided by the secon d

cutter with an air nozzle directed at the pool. This attempt

was not very successful because the arc was not stable.

Direct current electrode positive (DC EP) w as tried, and

the result made air carbon arc c utting practical. The b asic

principle remains the same today, but the equipm ent and

applications have been improved and expanded.

In 1948, the first

air carbon arc torch was introduced to

the welding industry. No longer were tw o cutters needed.

The air was fed through the torch and out beneath the

electrode at the correct location. This new tool was fou nd

to save time on backgouging of welds and removal of

cracks and other weld def ects on carbon, alloy, and stain-

less steels. Previously, this

type

of work had been done by

grinding or chipping. As the use of the CAC-A e xpanded,

torches were designed for more efficient and cleaner meta l

removal and for cutter comfort.

1.4 Applications. The CAC-A process is used through-

out industry

in

a variety of applications,

such

as m etal

fabrication and casting finishing, chemical and petro-

leum technology, construction, mining, general repair,

and m aintenance. CAC-A torches and e lectrodes are used

to create groove weld preparations in plates butted to-

gether.

If

the process is performed properly a minimal

1




S T D - A W S

C5.3-ENGL 2 0 0 0

07842b5 0520045

752

AWS C5.3:2000

amoun t of additional clean ing and grinding is required.

The CAC-A p rocess can then be used

to

backgouge the

joint to sound metal to ensure complete joint penetration.

If during welding, a problem arises and an area of the

weld does not meet specifications, the CAC-A process

can be used to remove

the

defective weld metal without

damaging

or

detrimentally affecting the base metal. The

CA GA process

is

used

in

the foundry industry to remove

f ins and risers from castings and then used to wash the

contact areas smooth with the surface in preparation for

shipment of the casting. The air carbon arc process pre-

sents great flexibility, efficiency, and cost effectiven ess

when ap plied to practically any type of metal. Carbon

steel, stainless steel, gray, malleable, and ductile iron,

aluminum, nickel, copper alloys, and other nonferrous

metals can be worked on with CAC -A.

2.

Referenced Standards

The following standards contain provisions which,

through reference

in

the text, cons titute provisions of this

AWS standard. For da ted references, subsequent amend-

ments to, or re visions of, any of these publications do not

apply. However, parties to agreemen ts based on this AWS

standard are encouraged to investigate the possibility of

applying the m ost

recent

editions of the docum ents shown

below. For undated references, the latest edition of the

standard referred to applies.

1) ANSI 249.1, Safety in Welding, Cutting, und Al -

(2)

AWS F1.l, Methods of Sampling Airborne Partic-

Available through:

lied Processes

ulates Generate d by Welding and Allied Processes


550 N.W. L eJeune Road

Miami, FL 33126

(3) OSHA Safety and Health Standards, 29CFR Part

Availab le through:

1910

Occupational Safety and Health Administration

200

Constitution Avenue NW

Washington, DC 20210

3. Fundamentals of the Process

3.1 General. CAC-A requ ires an arc to develop a mol-

ten pool on the w orkpiece. Compressed air is introduced

to blow away this molten me tal. The process requires a

welding power

source.,

a source of compressed air, car-

bon electrode, and cutting torch. Figure

1

shows the typi-

cal arrangement for using

this

process.

Except for special applications discussed later, CAC-

A is used with DCEP (reverse polarity). Th e electrode

should have a maxim um exten sion of 7 in.

(180

mm) from

the cutting torch, with the a ir je t between the electrode

and the workpiece. Although there is no minimum exten-

sion, care should be taken to prevent damage to the torch.

Therefore 1-1/2 to 2 in. (38

to

51 mm)

minimum

exten-

sion

is

recommended. Progression should only be

in

the

direction of air flow. The electro de push an gle will vary,

depending on the operation being performed. The cutter

should maintain the correct arc length to allow the air jet

to properly remove the molten metal (see Figure 2).

3.2

Power Sources. Single-phase input machines with

low open-circuit voltage are generally inadequate for

CAC-A. However, any three-phase input welding power

source of sufficientcapacity may be used, provided the

manufacturer recommends its use for CAC-A. The open-

circuit voltage must be sufficiently higher than the re-

quired arc voltage to allow for voltage drop in the circuit.

The arc voltag e used

in

air carbon arc gouging and

cut-

ting ranges from

28

to

56

volts (V); thus, the open -circu it

voltage should be at least 60V.The actual arc voltage

in

air carbon arc goug ing and cutting is governed to a large

extent by arc length and the application .

3.3

Compressed

Air. Standard comp ressed air is satis-

factory for CAC-A. Between

80

psi 413.7P a ) and

100

psi

690 kPa) pressures at the torch are normally used. Higher

pressures may be used, but offer little advantage in m etal

removal efficiency. Pressures as low as 40 psi (280 kPa)

have been used with som e manual torches

in

field appli-

cations where only cylinders of compressed air are avail-

able. However, pressures this low are not recomm ended.

Regardless of the pressure used with manual torches, the

air hose supplying the conce ntric cable assembly should

have a minimum inside diameter (ID) of 3/8

in. (10

mm).

Mechanized torches with automatic arc length control

should have an air supply hose with a minimum ID of

1/2

in.

(13 mm).

Table 1 gives the consumption rate of compressed air

for the various types of manual and mechanized torches,

as well

as

the compressor power rating required for inter-

mittent and continuo us use. C ompressors should have a

standard receiver tank for the co mpressor rating. Refer to

Table 1 for suggested

ASME

receiver size for the torch

being used.

3.4 Electrodes

3.4.1 DC Copper Coated Electrodes. This type is

most widely used because of its comparatively long elec-

trode life, stable arc characteristics, and groove u nifor-

mity. These electrodes are made from a special m ixture

2




I lFFl..==I

I I DI

COMPR ESSED AIR

k

r l

I l

POWER

SOURCE

I l

I I ELEC

4

TRIG LEAD

CEP OR AC

TRODE

3RKPIECE

Figure 1-'Qpical Arrangement for the Air Carbon Arc Cutting Process

\

T RcH

WORKPIECE

-)

Figure

S H O W

Standard CAC-A

Torch

Works

3




STD-AWS C5.3-ENGL 2000

W 078L i2b5 05200Li7 5 2 5

AWS C5.3:2000

Table 1

Recommended Minimum Air Requirements

Recommended Compressor Rating

Air Pressure(') Air Consumption Intermittent Use Continuous Use Receiver Size

ï)pe

of Torch psi kPa cfm Wmin hp

kW

hp

kW

gal L

Light Duty(2) 40 280

8 227

0.5

0.4

1.5 1.1

60 227

General

Duty(*)

80 550 25 708 5.0 3.7 7.5 5.6 80 303

Multipurpose(3) 80 550 33 934 7.5 5.6

10

7.5

80

303

Automatid4)

60 414 46 1303

15 11.2

80 303

Notes:

( i )

Pressure while torch is in operation.

2) Accommodates flat electrodes.

3) Generally considered a foundry torch.

4) Requires some

kind of

mechanical manipulation.

of carb on and grap hite with a suitable binder. Baking this

mixture at the appropriate temperature produces dense,

homo geneou s graphite electrodes of low electrical resis-

tance which are then coated with a controlled thickness

of copper. The copper coating improves electrical con-

ductivity prov iding more efficient, cooler operation and

helps maintain electrode d iameter at the point of the arc.

These electrodes are available in the following diameters:

1/8,5/32,3/16, 1/4,5/16,3/8, 112,518,

and

314 in. 3

mm,

4 mm, 5 mm, 6 mm, 8 mm, 10 mm, 12 mm, 16 mm, and

19

mm).

Jointed electrodes are available for op eration without

stub loss. They are furnished

with

a female socket and a

matching male tenon and are available

in

the following

diameters:

5/16,3/8,1/2,5/8,3/4,

and

1

in.

(8

mm,

10

mm,

12 mm, 16 mm, 19 mm, and 25 mm).

In addition to cylindrical electrodes, there are flat

(rectangular) coated electrodes

in

the following sizes:

5/32 x 318

and

3/16

x 518 in.

4

mm x

10

mm and 5 mm x

16 mm). These are used for ma king rectangular grooves

and for the removal of weld reinforcements.

3.4.2 DC Uncoated Electrodes. Of limited use, these

electrodes are generally used in diameters of less than

318 in. 10 mm). D uring cutting these electrodes are con-

sumed m ore rapidly than the coated electrodes. They are

manufactured the same a s the coated electrodes without

the coppe r coating. Plain electrodes are available in the

following diameters: 1/8,5/32,3/16,1/4,5/16,3/8,1/2,5/8,

3/4, and 1 in. 3 mm, 4 mm, 5 mm, 6 mm, 8 mm, 10mm,

12

mm,

16

mm,

19

mm, and 25 mm).

3.43 AC Copper Coated Electrodes. The following

electrodes are made from a special mixture of carbon and

graphite with a suitable binder. R are-earth materials are

incorporated to provide arc stabilization for

cutting

with

an alternating current. These electrodes, coated with a

controlled thickness of copper, are available in the fol-

lowing diameters: 3/16,1/4,3/8, and 112 in.

(5

mm, 6 mm,

10 mm, and 12 mm).

3.5 Gouging and Cutting Leads. Table 2 gives the

rec-

ommended number and sizes of cutting leads for differ-

ent currents and lengths.

3.6 Manual Cutting Torches.A

typical manual torch is

shown in Figure 3.The electrode is held in a rotating head

which con tains one or more a ir orifices, so that, regard-

less of the angle at which the electrode is set with respect

to the cutting torch, the air jet rema ins in alignmen t with

the electrode. Cutting torches with two heads (the air jet

is on two sides of

the

electrode) or with a fixed angle be-

tween the electrode and the holder, are preferred by som e

users for special applications. Normally, cutting torches

are air cooled. For high-current applications, water-cooled

cable assemblies are available and may

be

used with heavy-

duty torches.

3.7 Mechanized Cutting Torches. There are two m eth-

ods of controlling mechanized CAC-A torches. E ither

system is capable of ma king grooves

of

consistent depth

to a tolerance of 0.025 in.

0.6

mrn). These uni ts are

used where high quality, high productivity, or gouges in

excess of 3 ft

900

mm) long are desired (see Figure 4).

They are as follows:

3.7.1 Amperage Control.

An amperage-controlled

type which maintains the arc current by am perage signals

through solid-state controls. This type of system controls

4




AWS

C5.3:2000

Table 2

Recommended Number and Size of Gouging and

Cutting Leads for Various Currents(l)I2) and Lengths@)

4)

25 feet

8

m)

50

feet 15 m)

100

feet

30

m

150 feet 46 m)

200

feet 61

m)

250 feet 76 m)

(Amperes) No. Size No. Size No. Size No. Size No. Size No. Size

Current

~~ ~ ~~~

100

1 4 1

3 1

2 1

1

O 1

U0

1

410

200

1 3 1

2

1

1O

1

310

1

310 3 310

300

1

2

1

2

1 310 2

U0

2

410 4 410

400 1

2 1 1

O

1 410 2

410 3

410

5 410

500

1 1 1 U 2 210 2

410

4

410

2 410 5 410

00 1

1 1 310

2

800

1 1O

2 U0

2

410 410

410

310

4

1 410

3

310 5

310

410

3

410

410 4

310

lo00

1

1200

1

1400

1 410 2

1 m 5 ) 2

310

4 310

4

410

1800 2 410 4 4fO

2 m h )

3

410

5 410

210 2

Notes:

( i )

Recommendations based o n

4V,

dc loss/lOO

f i 30 m).

2)

For ac

use

next high er size of cable.

3) Length given is one ha lf the sum of the electrode and the work piece leads.

4) Impr ope r workpie ce conn ection causes cable overheating; at least 1 in.

25

mm) o f contact length should be used. Be sure the conn ection is tight.

5) Over

1600

amps, a heavy-duty air- coo led cable

should

be used.

6) Over 2000 amps, a heavy-du ty water-cooled cable must be used.

f EVER

1

IRVALVE

LHEAD

L NSULATOR

SEE

HEAD DETAIL

BELOW BODY

FEMALE CONNECTOR

\

1

LECTRODE

CABLE COVER

2

COMPRESSED AIR

y

AIR JETS

HEAD DETAIL

Figure

&Manual Torch

5




~

~~

S T D - A W S C5-3-ENGL

2 0 0 0 0 7 8 9 2 b 5

05200117

3 r d

AWS C5.3:2000

Figure Mechanized Cutting Torch

the electrode feed speed, which maintains the preset

amperage and can be operated with constant-potential

power s ource s only.

3.7.2

Voltage Control. A voltage-controlled type

which maintains arc length by voltage signals through

solid-state electronic controls. This type controls the ar c

length determined by the p reset voltage, and can be

used

with co nstant-c urren t power sup plies only.

3.73

Dual System.

A

dual system

is

capab le of oper-

ation by an internal selector switch in either of the m odes

described above.

3.8 Vacuum Gouging.

In

the late

1980s

a new variation

of gouging w as developed called vacuum gouging. This

process replaces the air jet used to evacuate

the

molten

slag from the groove area with a high-volume vacuum.

This process not only captures the slag and fume associ-

ated with the gougin g process, but also reduces the noise

level created when perform ing the gouging process.

The vacuum goug ing process is done using a specially

designed nozzle that attaches to the automatic gouging

head.

By

water cooling the nozzle and attached vacuum

hose, the slag and fum e from the gouging process

is

pulled

by the vacuum into a capture drum. The slag is knocked

into the bottom of

the

catch tank, which is partially filled

with water, and

the

fume is caught in a filter before the

air is exhausted from the vacuum.

This new vacuum gouging system at present

is

limited

to automated gouging operations on flat plate or pressure

vessel circum ferential seams.

4. Operating Techniques

4.1 Gouging. The electrode is gripped, as shown in Fig-

ure

3,

o

that a maximum

of 7

n.

(180

mm) extends from

the cutting torch. For aluminum , this extension should

be

reduced to

3

in. 76mm). Table 3 shows suggested cur-

rent ranges for various electrode types and sizes.

The air jet sh ould be turned on before striking the arc,

and the cutting torch should be held as shown in Figure

5.

The torch should always be operated using the fore-

hand techn ique, ¡.e., the electrode and air jet pointed in

the direction of travel. Under proper operating condi-

tions, the air jet is expected to sweep beneath the elec-

trode end and remove all molten metal. The arc may be

Table 3

Suggested Current Ranges for Commonly Used Electrode Types and

Sizes

Electrode Diameter

DC, D CEP Polarity AC Electrode

(in.)

(mm)

Minimum (amperes) Maximum (amperes) Minimum (amperes) Maximu m (amperes)

1/8 3 30

60 2 250

5/32 4 90

150

300 400

3/16

114

5/16

318

112

518

314

1

5

6

8

10

13

16

19

25

200

300

350

450

800

loo0

1250

1600

250

400

450

600

100

1250

1600

2200

325

350

500

425

450

600

318 Flat 10 250 450

5/8Flat 16 300 500

6




S T D O A W S CS - 3 - E NGL

2 0 0 0

0 7 8 q 2 b 5 0520050 OLT

W

AWS

C5.3:2000

Figure %Flat Position Gouging

Figure &Vertical Position Gou ging

struck by lightly touching the electr ode to the workpiece.

The electrode sh ould not be drawn back once the arc is

struck. The g ouging technique is different from that of

arc w elding because m etal is removed instead of deposited.

A

short arc should be m aintained by progressing

in

the

direction of the cu t fast enough to keep up with metal re-

moval. Th e stea diness of progression controls the sm ooth-

ness of the resulting

cut

surface.

For

gouging in the vertica l position, the c utting torch

should be held as shown

in

Figure

6.

Gouging should be

done in a downhill directio n, which perm its gravity to as-

sist

in

rem oving the mo lten metal. Vertical gouging may

be done

in

the op posite directio n, but

it

is more diffcult.

Gou ging in the horizontal position may be done either

to the right

or

to the left, but always with forehand goug-

ing.

In

gouging to the left, the cutting torch should be

held as shown

in

Figure

7.

in gouging to the right, the

cutting torch

will

be reversed to locate the air jet behind

the electrode.

When gouging

in

the overhead position, the electrode

and torch should be held at an angle that will prevent

molten metal from d ripping on

the

cutter’s glove, as shown

in

Figure 8.

The depth of the groove produced is controlled by the

travel speed. Grooves up to 1

in. (25

mm) deep may be

made. However, the deeper the groove, the more experi-

ence is required of an operator to produce an acceptable

groove. Slow travel speeds produce a deep groove. Fast

speeds w ill produce shallow grooves. The width of the

groove is determined by the size of the electrode used

and

is

usually about 1/8

in.

(3 mm) wider than the elec-

trode diameter. Wider grooves may be made with an

electrode that is oscillated with a circular

or

weave motion.

When gouging, a push angle of 65 degrees from the

surfac e of the workpiece is used for m ost applications. A

steady rest

is

recommended

in

gouging to ensure a smoothly

Figure 7-Horizontal Position Gouging

Figure P v e r h e a d Position Gouging

7




STD-AWS C 5 - 3 - E N G L

2000 W 078112b5 0520053 T 5 b

AWS C5.3:2000

gouged surface. It

is

particularly advantageous for use

in

the overhead position. Proper travel speed depends on the

size of the electrode, base metal, cutting amperage, and air

pressure. Proper spee d, which produces a smooth hissing

sound , will result in a sm ooth gouge.

3/8 in. (9.5 mm) and 5 /8 in. (15.9

mm)

flat electrodes.

Maximum 450 amperes.

(2) Medium-Duty Ge ner al Pu rpo se Torch-accepts

5/32 in. (3.97 mm) to 3/8 in. (9.5 m m) round electrod es and

3/8 in. (9.5 mm) flat electrodes. Maximum loo0 amperes.

4.2 Cutting. Figure 9 shows the electrode

in

position for

cutting. in general, the cutting technique

is

the same as for

gouging , except that the electrode is held at a steeper an-

gle; that is, with a push ang le between 10 and 20 deg rees.

For cutting thick nonferrous metals, the electrode

should be held perpendicular to the workpiece surface,

with the air jet in front of the electrode in the direction

of

travel. With the electrode in this position, the metal may

then be cut by moving the a rc up and down through the

metal with a sawing mo tion.

4 3

Washing.

In

using the air carbon arc cutting process

for removing metal from large areas, such as the removal

of surfa cing metal and of riser pads

on

castings, the proper

position of the electrode is shown in Figure 10. The elec-

trode should

be

oscillated from side to side while pushing

forward at the depth desired.

In

pad wash ing operations,

a push an gle of 20 to 75 degrees from the vertical

is

used.

The 75 degree angle is used for light finishing passes,

while the steeper angle s allow deeper rough cutting to be

done with greater ease.

Particularly suited for this application are cutting

torches with fixed angle heads that hold the electrode at the

correct angle. With other types of torches, ca re should be

taken to keep the air jet behind the electrode. The steadi-

ness of the cutter determines the smoothness of the sur-

face produced.

4.4 Beveling. One beveling m ethod

is

to hold the elec-

trode, as in Figure 11(A), with the torch parallel to the

edge being beveled, and a work angle equal to

the

angle

of the bevel to be produced. The air jet is between the

electrode and workpiece surface. The second method is

to hold the electrode as in Figure 1 1(B) with the elec-

trode parallel to the edge be ing beveled and the electrode

angle at

35

degrees. The air jet is between the electrode

and the workpiece surface.

5.

Equipment Selection

5.1 Cu t t in g Torch . Chosen for the job being done,

torches range from light-duty farm and body shop sizes

to extra-heavy-duty foundry torches. The following is a

guide for torch use:

General Purpose Torches:

(i) Light-Duty General Purpose Torch-accepts

1/8

in. (3.2 mm) to 1/4 in. 6.5 mm) round e lectrodes and

(3) Heavy-Duty Gene ral Purpose Torch-accepts

5/32

in.

(3.97 mm) to 1/2

in.

(12.7 mm) round electrodes

and 3/8 in. (9.5 mm) and 5/8 in. (15.9 m m) flat electrodes.

Maximum 1000amperes.

(4) Extra-Heavy-Duty Gene ral Purp ose Torch-

accepts 5/32 in. (3.97 mm) to

5 / 8

in.

(15.9 mm) round

electrode s and

3/8

in. (9.5 mm) and 5/8 in. (15.9

mm)

flat

electrodes. Maximum 12 50 amperes.

5 )

Foundry-Heavy-Duty Torch-General foundry

work and heavy-duty fabrication. Limited to 1600 amps

with air-cooled cables and

2000

amps with water-cooled

cables.

(6)

Mec hanized Go ugin g Torches-Edge prepara-

tions and backgouging, high quality and high produc tivity

uses. Used with 5/16 in. (8 mm) through 3/4 in. (19 mm)

jointed carbon electrodes.

5.2 Pow er Sources. Any three-phase input welding power

source of sufficient capacity may be used for the air carbon

arc gouging process, providing the manufacturer recom-

mends its use for CAC-A. However,

be

sure the open-circuit

voltage (OCV) is high enoug h to allow for voltage drop in

the circuit. The arc voltage used in air carbon a rc gouging

and cutting ranges from 2 8 to 56

V;

hus the open-circuit

voltage should be at least 60 V. Some constant potential

power sources require very high OCV to operate CAC-A

equipment. Single-phase input power sources require

very high O CV to operate CAC-A equipment. Single-

phase input power sources are generally inadequate for

this process. Power sources being used in conjunction

with mechanized cutting and other application s requiring

maximum arc time should be rated

100

duty cycle for

the required amperage.

5.2.1

Power Source Preferences. Choice of DC

power supply mode depen ds upon electrod e size:

(i)

DC-(Direct Current) Constant Curre nt (Motor

generator, transformer-rectifier, or resistor gr id unit).

Preferred power source for all electrode sizes.

(2) DC -C on sta n t Potential (Motor genera tor

or

tran sfo rm er rectifier). Usable only for 5/16 in. (7.9

mm)

and larger electrodes. May cau se carbon d eposits with

small electrodes. Not suitable for autom atic torches with

voltage control only.

(3) AC/DC hns form er- Rec tifier . Direct current (dc)

supplied from three phase transformer-rectifier supplies

is

satisfactory, but dc from single phase supplies gives

unsatisfactory arc characteristics. Alternating current

(ac) output from ac/dc

units

is satisfactory, provided ac

electrode s are used.

8




S T D - A W S

C 5 . 3 - E N G L

2000 0 7 8 i 4 2 b 5 0520052 772

9

AWS C5.3:2000

1-1/2 TIMES THE DIAMETER

IS THE MAXIMUM THICKNESS

THAT CAN BE CUT IN ONE PASS

FAVOR SIDE YC

ELECTRODE

b

e b

HOLD ELECTRODE PERPENDICULAR

TO

WORKPIECE WHEN PIERCING HOLES ONLY

Figure 9-Sev ering/Piercin g with CAC-A

PAMNASHINGTECHNIQUE

1.

TORCH REMAINS PARALLEL TO THE WORKPIECE.

2.

A WEAVING MOTION SIDE TO SIDE THE WIDTH OF THE AREA BEING CLEANED.

3.

MAINTAIN MOTION FORWARD ACROSS THE WORKPIECE.

4.

ELECTRODE PUSH ANGLE

IS 20 TO

75 DEGREES.

5.THE 20 DEGREE ANGLE

IS

USED MAINLY ON CAST IRON.

6.

HE MORE SHALLOW ANGLE THE SMOOTHER THE FINISH.

TRAVEL

Figure 10 -P ad Washing with CAC-A

9




STD-AWS C5 .3 - E NGL

2000

078112b5

0520053

8 2 7

AWS C5 3:2000

are particularly adaptable

to

producing long gouges in

flat workpieces with a moving gouging apparatus, and

for circular gouges in pipe and tanks with the gouging

apparatus remaining stationary. They pro duce a very con-

sistent U-groove configuration and can con trol depth of

the groove to within

0.025

in.

(0.6

mm). Tab les 4 and 5 give

typical operating condition s for both

U-

and J-grooves.

Figure 11-Methods of Beveling with CAC-A

(4) AC Constant Current Thosformer). Recom-

mended for ac elec trodes only.

5.3 Mechanized Systems. Mechanized system s are used

more

in

the fabrication industry. These systems offer a

high-quality, high-productivity alternative to manual cut-

ting. The re are

two

types of systems to be considered, both

operating on a signal from the arc to control the gouging;

dual signal system and single-signal system.

53.1 Dual Signal System. With this type of mecha-

nized system, either constant current or constant poten-

tial power supplies can be used. When utilizing constant

current, the arc length

is

maintained through a voltage

signal

system.

A predetermined voltage setting is set on

the system contro ller, which then advances or retracts the

electrode through a stepping motor to maintain the arc

length. On a constant potential power source, amperage

sensing controls the feeding or retracting of the electro de

to maintain the desired arc current.

53.2 Single-Signal System Voltage Control Only).

This type system als o maintains arc length through a volt-

age signal

as

above, but will not operate with an amperage

signal. This type

of

system operates only on a CC power

source.

5 . 33

Advantages.

Mechanized

CAC A systems

offer substantial improvem ents in both productivity and

quality. They a re capa ble of out-of-position gouging and

6. Process Variables

6.1 Introduction. The CAC A process is sensitive to

improper operation, as is any thermal cutting process.

Variables can cause chang es

in

the finished gouge that

range from indiscernible to unacceptable results. Primary

variables that require attention, along with the functions

resulting from those variables, are listed

in

Table 6.

6.2 Electrode Diameter and Type. This is the most

dominant factor

in

determining the size of

the

groove.

The proper choice of electrode can affect productivity,

groove quality, and metal rem oval rates. The width of the

groove will be approxim ately 1/8

in.

( 3

mm)

wider than

the diameter of the electrode.

In

choosing the proper

elec-

trode, the size of the desired groov e should be the decid-

ing factor, with available power dictating the maximum

electrode diameter. As an example, a

1/2 in.

(12 mm)

wide, 1/4

in. (6 mm)

deep groove

10 in. (254 mm)

long

could be made manually

in

two passes using a 1/4 in.

(6

mm) diameter electrode or

in

one pass with a 3/8

in.

9.5

mm) diameter electrode. in the former, the effective

gouging rate would be

10 in.

(254 mm) per

minute

per

pass. Therefo re the effective travel speed is 5 in. (127 mm)

per minute (10 IPM [254

mm]

divided by

2

passes). The

travel speed or gouging rate for 3/8 in. (10 mm) is 17 in.

(432

mm)

per minute. This is more than a 200 increase

in gouging rate and will offset the additional electrode

cost. M echanized systems even further increase the pro-

ductivity rate due to the finite control of the arc voltage.

6.3

Amperage. The gouging amperage determines the

melting rate of the process. it

is

determined by the elec-

trode size.

If

the amperage is set too low for the electrode

size, the melting rate of the base metal will be inadequate,

and free-carbon deposits will occur. A setting too high,

while melting the base metal, will cause rapid deterio-

ration of

the

electrode with subsequent reduction in metal

removed per electrode. This condition can also substan-

tially reduce torch life.

6.4

Voltage. Voltage is determined by the arc leng th and

the current flow through the arc.

CAC A

generally re-

quires a higher voltage than m ost welding processes. This

requirement limits proper operation to power sources w ith

10




AWS C5.3:2000

Power Data

Table 4

Mechanized CAC-A U-Groove Gouging Conditions

Overall

Speed

ravel Speed per Minute Pass

Electrode Diameter Desired

Depth

Travel Speed

(in.) (mm)

(in.)

(mm) (in./min) (mdmin) (amperes)

5116 8 118 3 65 1650 400

3/16 5 45 1140

114 6 36 9140

5/16 8 33 840

711 6 11 22 560

318 10 118 3 70 1780 500

3/16 5 44 1120

1 4 6 35 890

318 10 20 510

9/16 14 17 430

112 13 118 3 96 2440 850

114 6 57 1450

318

10

35 890

1

I2 13 24 610

314 19 18

460

518 16 114 6 72 1830 1250

318

10

48 1220

1 2 13 37 940

518 16 30 760

718 22 20 510

314 19 318 10 42 1070 1400

i l 2 13 34 860

518 16 27 690

314 19 22 560

1 24 18 460

General Note: If the groove depth

is

i ln

imes

the electrode diameterbeing

used

make two or more

passes.

Table 5

Automatic CAC-A J-Groove Operating Data

Material

Size

in. mm)

318 1

O

112 13)

518 16)

314 19)

1.5 38)

2 50)

Electrode Data

5/16 8)

318 10)

3/8 10)

518 16)

518 16)

518 16)

45 4 10)

45 4 10)

45 4 10)

45 4 10)

45 4 10)

45 4 10)

Electrode Overhang (in. ) Pass

1

in. mm)

.O63 1.6)

.O63 1.6)

.O63 1.6)

.125 3.2)

.i25 3.2)

.o63 1.6)

.o63 1 6)

.o63 1.6)

.125 3.2)

l

in. (cm)

65 165)

35 89)

50 127)

37 94)

40 1021

47 119]

28 (71)

50 127)

40 102)

37 94)

in. (cm)

65 165)

35 89)

25 64)

18.5 47)

20 51)

16 41)

9.5 10)

11




STD*AWS

AWS C5.3:2000

C 5 . 3 - E N G L 2000

0 7 8 q 2 b 5

0 5 2 0 0 5 5 b T L

Table

6

Primary Process Variables

Variable Function

Electrode diameter Determines the size of the groove.

Amperage

Voltage

Air

pressure

and flow rate

Travel speed

Electrode

travel

and work angle

Electrode

extension

Base metal

Determined by the diameter of electrode

being used.

It

is the current flow performing

the melting of the base metal

The

electric potential

behind the

amperage,

or the arc force. Determined by arc length

on CC power supplies and set on CV power

supplies.

The medium for removal of

the

molten

metal.

Determines the depth

and

quality of finished

grooves.

Can

determine

groove shape.

Affects metal removal rates

and quality

of

groove.

Determines selection

of parameters for

other variables.

high enoug h open-circuit voltage to maintain a

28

V oper-

ating minimum. Inadeq uate voltage can create a sputter-

ing

arc

or

actually prevent arc establishment. This results

in uneven gro oves with a high probability of free- carbon

deposits, requiring exce ssive grinding to remove.

6.5

Air

Pressure and F low Rate. The air jet is the me-

dium for the removal of the m olten metal. Both adequa te

pressure and flow rate are required to obtain the proper

results. This variable is probab ly one of the most abused

of all the variables discussed. Th e flow rate

in

cubic feet

per m inute (cfm) is as im portant as the air pressure. The

pressure

is

the variable that dete rm ines the velocity of the

air that moves the molten metal out of the groove area. If

there is not enough flow to lift the molten metal out of

the groove, the air jet cannot rem ove the molten metal, re-

sulting in excessive slag adhesion and unnecessary grinding

to clean the groove, This is necessary to ensure that the

air supply system

possesses

an adequate receiver (reservoir)

in order to maintain the required flow rate (see Table i).

6.6 Travel Speed. Travel speed is the variable that di-

rectly

affects the depth of the go uge as w ell as the result-

ing quality of the groove. T he faster the travel for any

given diamete r electrode, the shallow er the gouge. If the

travel speed is too fast for the cutter’s comf ort, a sm aller

electrode size should be used, or a move to mechanized

gouging should be considered. Attempting a groove too

deep

for

the electrode diameter creates a poor quality

groove that requires exce ssive grinding.

6.7 Electrode Push Angle. The electrode push angle is

the most forgiving of the process variables. When goug -

ing manually, a greater ang le tends to prod uce a mor e Vee

shaped groove. With the mechanized system, a greater

angle will produce a slightly deeper groov e with the same

travei speed as a groove made with a lesser angle.

6.8 Base Metals

6.8.1

Gouging Recommendations.

Gouging recom-

mendations are provided in Table 7.

6.8.2 Effectsof the Cutting Process on Base Metals.

To avoid difficulties with carburized metal, users of the

CAC-A process should be aw are of the metallurgical events

that occur during gouging and

cutting.

With DCEP, and

the corresponding half cycle of ac, the current flow car-

ries ionized carbon atoms from the electrode to the base

metal. The free carbo n particles are rapidly abso rbed by

the melted base metal. Increased carbon can lead to in-

creased hardness and possible cracking. Since this absorp-

tion cannot be avoided, it

is

impo rtant that all carburized

molten metal be removed from the cut surface, preferably

by the air jet.

When the CAC-A process is used under improp er con-

ditions, the carburized molten m etal left on the surface

may usually be recognized by

its

dull gray-black color.

This is in contrast to the bright blue color of the properly

made groove. Inad equate air flow may leave small poo ls

of carburized metal in the bottom of the groove. Irregular

electrode travel, which is particularly true for manual

gougin g, may produce ripples in the groo ve wall that tend

to trap the carburized metal. Finally, an improper elec-

trode push angle may cause small beads of carburized

metal to remain alo ng the edge of the groove.

The effect of carburized metal on the cut surface dur-

ing subsequ ent welding depend s on m any factors, includ-

ing

the amount of carburized metal present, the welding

process to be employed, the kind of base metal, and the

weld quality required. Although

i t

may seem that filler

metal deposited

on

the surface during welding should

as-

similate small pools

or

beads of carbu rized metal, experi-

ence with steel base metals shows that traces

of

metal

containing approximately 1 carbon may remain along

the weld interface. The effect of these carburiz ed depos-

its become m ore significant with dem ands for increasing

weld strength and toughness,

There is no evidence that the copper from copper-

coated electrodes is transferred to the cut surface i n base

metal, except when the process is improperly used.

12




~

STDmAWS C 5 - 3 - E N G L 2000 m 0 7 8 ’ 4 2 b 5 052005b 538

AWS C5.3:2000

Table 7

Gouging Recommendations

Base Metal Recommendations

Carbon steel and low-alloy steel, such as

ASTM A

514

and A

517

Stainless steel

Cast iron, including gray, malleable, and

ductile iron.

Use dc electrodes with DCEP (electrode positive). AC electrodes with an AC transformer

can

be used, but

for

this

application, ac

is

only

50%

as

efficient as dc.

Same

as

for carbon steel.

Use of 1/2

in.

(12 mm) or larger electrodes at the highest rated amperage is necessary.

There are also special techniques that need to be used when gouging these metals. The

push angle should be at least 20 degrees and depth of the cut should not exceed 1/2

in.

(13 mm) per pass.

Copper

alloys

Use dc electrodes with DCEN at

maximum

amperage rating of the electrode or use ac

electrodes with ac.

Aluminum bronze and aluminum nickel

bronze (special naval propeller alloy)

Nickel alloys (nickel content is over

80 )

Nickel alloys (nickel content less

than 80 )

Use dc e lectrodes with DCEN.

Use

ac electrodes with ac.

Use ac electrodes with DCEP.

Magnesium alloys

Aluminum

Use ac electrodes with DCEP. Before welding, surface of groove should be wire

brushed.

Use dc electrodes with DCEP. Wire brushing with stainless wire brushes is mandatory

prior to welding. Electrode extension (length of electrode between electrode torch and

workpiece) should not exceed 3 in.

(76

mm) for good quality work. DC electrodes with

DCEN can also be used.

Titanium , zirconium, hafnium, and their

alloys

Should not be cut or gouged in preparation for welding or remelting without subsequent

mechanical removal of surface layer from cut surface.

Carburized metal

on

the cut surf ace may be removed

by grinding, but it is much more efficient to conduct air

carbon arc gouging and cutting properly within prescribed

conditions to completely avoid the retention of undesir-

able metal.

Studies have been conducted on stainless steel to de-

termine whether air carbon arc gouging, carried out in

the prescribed manner, would adversely affect corrosion

resistance. Re sults of the studies are shown in Table 8.

Type 304L stainless steel was welded using several pro-

cesses.

Backgouging

of

the

joint was performed by air

carbon arc gouging and by grinding. Specimen s from the

joint s were subjected to the boiling 65 nitric acid test.

Corrosion rates typical for Type

304L

stainless steel

were obtained, and the results showed no significant dif-

ference in the corrosion rates

of

welds prepared by CAC-A

and those prepared by grinding. Had any appreciable carbon

absorption occurred, the corrosion rates for welds back-

gouged by CAC-A would have been significantly higher.

Compared to oxyfuel gas cutting, CAC-A is a higher

energy process which results

in

lower heat input to the

base metal. Therefore, a workpiece gouged

or

cut by CAC-A

i s less

distorted than oxyfuel gas cutting.

The

machin-

ability of low carbon and nonhardenable steels

is

not af-

fected by the CAC-A process. With cast iron and high-

carbon steels, however, this process may make the cut

surface extremely hard. Nevertheless, because the hard-

ened zone is shallow (approximately 0.06

in. [1.5

mm]), a

cutting tool is able

to

penetrate the hardened z one and re-

move this layer.

7.

Advantages and Limitations

7.1 Advantages

7.1.1 Fast. Gouging with CAC-A is five times faster

than chipping; it goug es a groove 3/8 in. (10 mm) de ep at

over

2

feet per minute

(0.6

M/M .

7.1.2 Easily Controllable.

CAC-A removes defects

with precision. Defects are clearly visible in the groove

and may be followed with ease. The depth of the cut

is

easily regulated, and slag do es not deflect

or

hamper the

cutting action.

13




AWSC5.3:2ûûû

Table 8

Results of Corrosion Testing on Type 3û4L Stainless Steel

Corrosion Rate (per month)

Specimen

Identification Welding Process Welding Position Root Preparation in.

mm

HC1

HC2

HG1

HG2

VCl

VC2

VG

OG

oc

GMAW

GTAW

GMAW

GTAW

GMAW

SMAW

SMAW

SMAW

SMAW

Horizontal

Horizontal

Horizontal

Horizontal

Vertical

Vertical

Vertical

Overhead

Overhead

CAC-A Gouging

CAC-A Gouging

Grinding

Grinding

CAC-A Gouging

CAC-A Gouging

Grinding

Grinding

CAC-A Gouging

0.000593

0.000594

O OOO646

0.000618

0.000686

0.000627

0.000667

0.000632

0.000645

0.01505

0.01509

0.01640

0.01570

0.01742

0.01593

0.01695

0.01605

0.01638

7.13

Low

Equipment Cost.

No

gas cylinders or reg-

ulators are necessary excep t

in

field operations.

7.1.4 Economical to Operate.

No oxygen or fuel gas

is required with CAC-A. The w elder or welding operator

may also

do

the gouging o r cutting.

7.1.5 Easy to Operate. Welders operate the equip-

ment after a few minu tes of instruction and become pro-

ficient in a few days. Th e torch con tains an air-control

valve and rotating noz zle that perm its changing the elec-

trode position to suit the job while m aintaining alignment

of the air jet.

7.1.6 Compact.

The torch

is

not much larger than a

shielded metal arc electrode holder.

7.1.7 Versatile. CAC-A is used anywh ere it

is

possi-

ble to weld. It may be operated

in

spaces too restricted to

accomm odate a chipping hammer or an oxyfuel gas cut-

ting torch. It requires no difficult adjustm ents for use on

different metals.

7.1.8 Cuts Cleanly.

The

resulting surface of CAC-A

is

clean and smooth. Welding may generally

be

performed

with a minimum of grinding or cleaning.

7.2 Limitations

i)

Other cutting proc esses are better for severing.

(2)

CAC-A requ ires a large volume of com pressed air.

(3) CAC-A increases the surface hardn ess on cast iron

(4) The CAC-A process

is

accompanied by noise,

and air harde nable metals. This may be objectionable.

fum es, and a discharge of sparks and molten metal.

8.

Troubleshooting

The CAC-A problems versus solutions shown in

Table

9 can

be used for troubleshooting.

9.

Safe Practices

9.1

Introduction.

The general subject of safety and saf e

practices in welding and thermal cutting processes, such

as CAC-A, is covered in AN SI 249.1, Safely in Welding,

Cutting, andAll ied Processes. Air carbon arc cutters and

their supervisors should be familiar with the practices

discussed in these documents. Other safety sources are

listed in Annex B.

In

addition, there are other potential hazard areas

in

arc

welding and cutting (other than fumes,

gases,

and radiant

energy), such

as

noise and improper use of pres sure regu-

lators, which warrant consideration. Those areas a ssociated

with CAC-A are briefly disc ussed in this section.

9.2 Noise. Excessive noise is a known health hazard.

Exposure to excessive noise can cause a loss of hearing.

The loss

of

hearing can be either full or partial, and tem-

porary or permanent. In welding, cutting, and allied op-

erations, noise may result from the process, the power

source, or other equipment. Air carbon arc and plasma

arc are exam ples of proce sses which are freq uently noisy.

Engines of engine-driven generators m ay also be quite

noisy.

Excessive noise adversely affects hearing capability.

This adverse effect upon hearing capab ility may

be

a tem-

porary threshold shift from wh ich ears may recover if re-

moved from the noise source. However, if a person is

exposed to the sam e noise level for a longer time, then

the loss of hearing may become permanent. Th e time re-

quired

to

develop permanent hearing loss depends upon

factors such as individual susceptibility, noise level, an d

expos ure time. In add ition, there is evidence that exces-

sive noise affects other bodily fu nctions and behavior.

A

direct method to protect against excessive

noise

is

to reduce the intensity of the source. Another method

is

14




STD-AWS C 5 . 3 - E N G L 2 0 0 0

0 7 8 4 2 b 5

0520058 300

AWSC5.3:2OOO

Table

9

CAC-A Troubleshooting

Problem Cause/Remedy

Large free-carbon deposit at

the beginning of the groove.

The operator either neglected to

turn

on the air jet before striking the arc, or the torch was located

improperly. The air should be turned on before striking the arc and should flow between the elec-

trode and the workpiece behind the electrode

in

the direction of travel.

An unsteady arc, causing the

cutter to use a slow travel

speed even on shallow

grooves.

The amperage was insufficient for the electrode diameter used (see Table

3).

While the minimum

recommended amperage may be sufficient,

it

does require a higher degree of operator skill. The mid-

dle of the range is much more efficient. If the desired amperage cannot be obtained from the avail-

able power source, greater efficiency would be obtained by using a sm aller diameter electrode.

Erratic groove with the arc

wandering from side to side

and with the electrode heating

rapidly.

Intermittent arc action

resulting in an irregular

groove surface.

~~~~~

The process was apparently used with DCEN (electrode negative). Direct current electrodes should

be used with DCEP on all metals, with the exception 8f a few copper alloys.

The travel speed was too

slow in

manual gouging. Generally, the operator has fixed his or her posi-

tion by setting a hand on the workpiece. Since the speed of air carbon arc gouging is much faster

than shielded metal arc welding, friction between the gloved hand and the workpiece may cause an

erratic forward motion. This causes the arc length between the electrode and workpiece to become

too large to maintain the arc. The cutting operator should assume a comfortable position

so

that his

or her arms can move freely and the gloves do not drag on the work. If mechanized equipment

is

involved, check Tables

4

and 5 or proper operating conditions.

In gouging, carbon deposits

left at intervals along the

groove; in pad washing,

carbon deposits at various

spotson the washed surface.

The electrode has shorted out on the workpiece. In manual gouging, this condition is caused by

using travel speed excessive for the amperage used and for the depth of the groove being made.

In

mechanized operations, it is caused either by excessive travel speed or by using a flat-curve constant

potential power source for a small diameter electrode of 5/16 n. (8 mm). In pad washing, this short-

ing out iscaused by holding the electrode at too large a push angle. An electrode push angle of

20

to

75

degrees from the vertical is recommended. A larger angle increases the arcing area, which

reduces the current density. This reduction in arc current density requires a decrease in arc length, to

the point of short circuiting. Care

must

be taken to maintain the proper arc gap.

Irregular groove, too deep,

then too shallow. gouging.

Slag adhering to the edges

of the groove.

The operator was unsteady. The operator should relax and assume a comfortable position when

Slag ejection was inadequate. For adequate slag ejection, proper air pressure and flow rate should be

used. Air pressure, between 80and

100

psi 550-690 kPa), may not effectively eject all of the slag

if

the volume

is

insufficient. To deliver adequate volume, the air hose feeding the concentric cable

assembly should have a minimum ID of

3/8 in.

(10 mm) for manual torches. For mechanized torches

that do not require a concentric cable, the

minimum

hose ID should be 1/2

in.

13mm).

to shield the

source,

but this h as limitations. Th e acousti-

cal characteristics of a room will also affect the level

of

noise.

When engineer ing control methods fail to reduce

the noise, personal protective devices such a s ear muffs

or ear p lugs may be employed. G enerally, these devices

are

only

accepted whe n engineering con trols are not fully

effective.

Th e permissible noise exposure limits can be found

in

the CFR Title 29, Chapter XVII, Part

1910.

Additional

information may be found in the Threshold Limit Values

fo r Chem ical Substances and P hysical Agents Biological

Exposure Limits.

Information on obtaining these docu-

ments can be found in Annex B.

9 3

Gases. The major toxic

gases

associated with the air

carbon arc process are ozone, nitrogen dioxide, and car-

bon monoxide. Pho sgene gas could be present a s a result

of thermal or ultraviolet decomposition

of

chlorinated

hydrocarbon cleanin g agents or suspen sion agents used

in some aerosol anti-spatter agents

or

paints. Degreasing

or other operations involving chlorinated hydrocarbons

should be so located that vapors from these operations

cannot be reached by radiation from the arc.

93 1 Ozone.

Th e ultraviolet light emitted from the arc

acts

on

the oxygen

in

the surrounding atmosphere to pro-

duce ozone. Th e amounts

of ozone

produced will depend

15




STD-AWS C 5 . 3 - E N G L 2000

0 7 8 L i 2 b 5

0520059

247

W

AWS C5.3:2000

upon the intensity and the wavelength of the ultraviolet

energy,

the

humidity, the amount of screening afforded by

the fum e, and other facto rs. The oz one conc entration will

generally be increased with an increase

in

current and when

aluminum is cut or gouged. T he concentration can be con-

trolled by natural ventilation, local exhaust ventilation, or

by respiratory protective equipment described

in

ANSI

249.1.

93.2

Nitrogen Dioxide. Some tests have shown that

high concentrations of nitrogen dioxide are found only

close to the arc. Natural ventilation reduces these con-

centrations quickly to safe levels

in

the cutter’s breathing

zone, so long as the cutter keeps his or her head out of

the fume plume.

9 3 3

Metal Fumes. The fumes generated by the

CAC-A process can be controlled by natural ventilation,

local exhaust ventilation, or by respiratory protective

equipmen t described

in

ANSI

249.1.

The method

of

ven-

tilation required to kee p the level of particu late and gas es

in

the operator’s breathing zone within acceptable con-

centrations is directly dependant upon a number of fac-

tors, among which are the metal being cut or gouged , the

size of the work area , and

the

degree of confineme nt or

obstruction to the normal air movement where the opera-

tion is taking place.

Each operation should be evaluated on an individual

basis in order to determine what will be required. See

Table 10 for the spec ific particulate matter that may be

present for cutting sp ecific base metals. Acceptable lev-

els of particulate matter associated with cutting and de s-

ignated as time-we ighted average threshold

limit

values

(TLVs)

and ceiling values have been established by the

American Conference of Governmental Industrial

Hy-

gienists and by the O ccupational Safety and Health Ad-

Table 10

Particulate Matter with Possible

Significant Fume Concentration

in the

Arc

Cutter’s Breathing Zone

~ ~~ ~~~

Base

Metal Particulate Matter

Aluminum

and aluminum alloys

Magnesium alloys Mg,

Al,

Zn

Copper

and copper

alloys

Nickel and nickel alloys

Titanium and

titanium

alloys

Austenitic stainless steels

Carbon steels(’) Fe,

Cu,

Mn

Note:

(1) Also Cd.

Sn, and

Zn

for plated

base metals.

AI,

Mg,

Mn,

Cr, Si

Cu,

Be,

Zn,

Pb,

Sn,

Si

Ni, Cu, Cr, Fe

Ti, Al,

V

Cr, Ni,

Fe, Mn

ministration. Compliance with these levels can be tested

by a sampling of the atmosphere under the cutter’s hel-

met or

in

the immediate vicinity of the cutter’s breathing

zone. Samples should be

in

accordance with AWS F1.l,

Methods for Sampling Airborne Particulates Gen erated

by Welding and Allied Proc esses.

9.4

Radiant Energy.

Any person within the immediate

vicinity of the cutting arc should have adequate p rotec-

tion from ra diation produced by the cutting arc. The filter

shade recommended for CAC-A is a shade twelve (12) or

greater. For less than

500

A 12 is acceptable; for greater

than

500

amps

use

a shade fourteen (14). Le ather or wool

clothing that

is

dark in color is recommended to better

withstand

the

vigors of radiation, better resist burning,

and to reduce ultraviolet burns to the neck and face be-

neath the helmet.

10.

Bibliography

(1)

American Welding Society. Welding Handbook,

Vol. 2, 8th Ed., 489-496; Miami: American Welding

Society, 1991.

(2) Christensen, L. J. “Air carbon a rc cutting.” Weld-

ing Journal

52(12): 782-791;

1973.

(3) Franz, R. “Maintenance w elding for excavators.”

Welding Design Fabrication 45(10): 49-50 1972.

4)Hard, A.

R.

“Exploratory tests of the air carbon

arc cutting process.” Welding Journal 33(6): Res. Suppl.

(5)

Hause, W.

O.

“What you should know about air

carbon a rc metal removal.” Welding Desig n

di

Fabrication

(6) Ma rshal l, W. J. et al. “Optical radiation le vels pro-

duced by air carbon a rc cutti ng processes.”

Welding

Journal 59(3): 43-46,1980.

(7) Oliver, T.

P.

and S anderson, J. T. “Arc air gouging:

the hazards and their control.” Journal of the Society

of

Occupational Medicine 23(4): 114119,1973.

(8) Panter, D. “Air carbon arc gouging.” Weld@

Journal 56 5): 32-37,1977.

(9) Prager, M. and Thiele, E.

W.

Welding a copper

nickel clad ship-ma riner II.” Welding Journal 58(7):

(10) Rida], E.

J.

“Preparation for welding by air carbon

arc gouging.” Welding Meta l Fabrica tion 45(6): 347-

353,356-362,1977.

(11) Soisson,

L.

and H enderson, J. “J-groove edge prep

comes easy w ith AAC.” Welding Design di Fabrication,

57(7):

53-55,

1983.

(12) Soisson, L. “Automatic

AAC

reduces edge prepa-

ration time.”

Welding Journal

65(5): 67-72,1986.

261-s to 264 -~ , 954.

51(1):

52-56,1978.

17-24,1979.

16

American Welding Society Inc.

Services

YRIGHT American Welding Society, Inc.ensed by Information Handling Services



S T D * A W S

C5.3-ENGL 2000 078L i 2bS

0 5 2 0 0 b 0 T b 7 W

AWS C5.3:2000

Annex A

Comm only Used

Metric

Conversions

(This

Annex

is not

a

part

of AWS

C5.3:2000,Recommended PracticesforAir Carbon

Arc Gouging

and

Cutting,

but

is included for

information

purposes only.)

Commonly Used Metric Conversions

(Inch-Millimeter Conversion)

1

in.

= 25.4 mm exactly

To convert inches to mill imeters, multiply the inch value by 25.4.

To convert millimeters to inches, divide the millimeter value by 25.4.

Inch Inch

Fractional Decim al Millimeter Fractional Decim al Millim eter

0.015 625 0.396 875 33/64 0.515 625 13.096 875

/64

1/32 0.031 250 0.793 750 17/32 0.531 250 13.493 750

13.890 625

/64 0 046 75

1.190 625 35/64 0.546 875

1/16 0.062 500 1.587 500

911 6 0.562 500 14.287 500

5/64 0.078 125 1.984 375 37/64 0.578 125 14.684 375

3/32 0.093 750

2.381 250 19/32 0.593 750 15.081 250

7/64 0.109 375

2.778 125 39/64

0.609

375 15.478 125

118 0.125o

3.175

o00

518 0.625

O00

15.875o

9/64 0.140 625

3.571 875 41/64 0.640 625 16.271 875

5/32 0.156 250 3.968 750 21/32 0.656 250 16.668 750

11/64 0.171 875

4.365 625 43/64 0.671 875 17.065 625

311 6 0.187 500

4.762 500 11/16 0.687 500 17.462 500

13/64 0.203 125

5.159 375 45/64 0.703 125 17.859 375

7/32 0.218 750 5.556 250 23/32 0.718 750 18.256 250

15/64 0.234 375

5.953 125 47/64 0.734 375 18.653 125

114 0.250 o

6.350

o

314 0.750 O00 19.050 O00

17/64 0.265 625

6.746 875 49/64 0.765 625 19.446 875

9/32 0.281 250 7.143 750

25/32 0.781 250 19.843 750

19/64 0.296 875

7.540 625 51/64 0.796 875 20.240 625

5/16 0.312 500 7.937

500

13/16 0.812 500 20.637 500

21/64 0.328 125

8.334 375 53/64 0.828 125 21 O34 375

11/32 0.343 750

8.731 250 27/32 0.843 750 21.431 250

23/64 0.359 375

9.128 125 55/64 0.859 375 21.828 125

318 0.375o 9.525 o 718 0.875o 22.225 O00

25/64 0.390 625

9.921 875 57/64 0.890 625 22.621 875

13/32 0.406 250

10.318 750 29/32 0.906 250 23.018 750

27/64 0.421 875

10.715 625 59/64 0.921 875 23.415 625

7/16 0.437 500

11.1 12 500 15/16 0.937 500 23.812 500

29/64 0.453 125

11.509 375 61/64 0.953 125 24.209 375

15/32 0.468 750

11.906 250 31/32 0.968 750 24.606 250

3 1/64 0.484 375

12.303 125 63/64 0.984 375 25.003 125

1 2 0.500 o 12.700

o

1 1.o00o 25.400 o

17




STD*AWS C 5 . 3 - E N G L

2000 0 7 8 4 2 b 5 05200bL 7 T 5

AWS C5.3:2000

Annex B

Safety References

(ThisAnnex

is

not

a

part of AWS C5.3:2000, Recommended Practices fo r Air Carbon Arc Gouging and Cutting, but

i s included for inform ation purposes only.)

The fo llowing references are listed by their source:

(1) ACGIH, Threshold Limit Values for Chemical

Substances and P hysical Agents B wlogical

E p s u w

Limits

Available through: ACGIH, 1330 Kemper Meadow

Drive, Cincinnati, OH 45240-1634; Phone: 513-742-2020

(2) ANSI 287.1, Practice for- ûcc upa tion al and Edu-

(3) ANSI 288.2, Respiratory Protection

Available through: American National Standards in-

stitute,

11

West 42nd S treet, 13th Floor, New York,

NY

10036-8002; Phone: 212-642-4900

cational Eye and Face Protection

(4) ANSI 249.1, Safety in Welding, Cutting, andAllied

Processes

5 ) AWS F4.1, Recommended Safe Practices for

Preparation fo r Welding and Cutting o Containers and

Piping

(6) AWS Health and Safety Fact Shee ts

Available through: American Welding Society, 550

N.W. LeJeune Road, Miami, FL 33126; Phone: 1-800-

334-9353

(7) Code of Federal Regulations (OSHA), Section 29

Part

1910.95,132,133,134,139,251,253,254,

and 1000

Available through:

U.S.

Government Printing Office,

Superintendent of D ocum ents, P.O. Box 37195 4, Pitts-

burgh, PA 15250-7954 ; Phone: 202-512 -1800

(8)

CSA

Standard W117.2, Safety in Welding, Cu tting

and Allied Pro cesses

Available through: CSA international, 178 Rexdale

Boulevard, Toronto,

ON;

Phone 800-463-6727

(9) NFPA 51B, Standard for Fire Prevention During

Welding, Cutting, and Other Hot Work

Available through: National Fire Protection Associa-

tion, 1 Batterymarch Park, P.O. Box 9101, Quincy , MA

02269-9101; Phone: 617-770-3000

19

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page is blank.




Annex C

Guidelines for Preparation of Techn ical Inq ui ries

for AWS Technical Com mittees

(This Annex i s not a part of AWS C 5.3:2000, Recommended Pra cticesfo r Air Carbon Arc Gouging and Cutting, but

is included for information purposes only.)

Ci. Introduction

The AWS Board of Directors has adopted a policy

whereby all official interpretations of AWS stand ards

will be handled in a formal manner. Under that policy, all

interpretations are m ade by the com mittee that is respon-

sible for the standard. Official communication concern-

ing an interpretation is through the AWS staff member

who w orks with that committee. The policy requires that

all

requests for an interpretation be submitted in writing.

Such requests will be handled a s expeditiously as possi-

ble but du e to the complexity of the work and

the

proce-

dures that must be followed, some interpretations may

require considerable time.

C2.

Procedure

All inquir ies must be directed to:

Managing Director, Technical Services

Ame rican Welding Society

550

N.W. LeJeune Road

Miami, FL 33126

All inquiries must contain the name, address, and af-

filiation of the inquirer, and they must provide enough in-

formation f or the committee to fully understand the point

of concern in th e inquiry. Where that point is not clearly

defined, the inquiry will be returned for clarification. For

efficient handling, all inquiries should be typewritten and

should als o be in the format used here.

C2.1 Scope. Each inquiry must address one single provi-

sion of the standard, unless the point of the inquiry involves

two

or

more interrelated provisions. That provision must

be identified in the scope

of

the inquiry, along with the

edition

of

the standard that contains the provisions or that

the inquirer is addressing.

C2.2Purpose

of

he Inquiry. The purpose

of

the inquiry

must be stated in this portion of the inquiry. The p urpose

can be either

to

obtain an interpretation of a standard

requirement, o r to request the revision of

a

particular pro-

vision in the standard.

C2.3 Content

of

the Inquiry. The inquiry should be

concise, yet complete, to enable the comm ittee to quickly

and fully understand the point of the inquiry. Ske tches

should be used when appropriate and all paragraphs, fig-

ures, and tables or the Annex), which bear

on

the in-

quiry must be cited. if the point

of

the inquiry is to obtain

a revision of the standard, th e inquiry must p rovide tech-

nical justification for that revision.

C2.4Proposed Reply. The inquirer should, as a pro-

posed reply, state an interpretation

of

the provision that

is

the point of the inquiry, or the wording for a proposed re-

vision, if that is what inquirer seeks.

C3. Interpretation of Provisions of

the Standard

Interpretations of provisions

of

the standard are made

by

the

relevant AWS Technical C omm ittee.

The

secre-

tary of the committee refe rs all inquiries to the chairman

of the particular subcom mittee that has jurisdiction over

the

portion of the standard addressed by the inquiry. The

subcomm ittee reviews the inquiry and the proposed reply

21

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STD=AWS C5.3-ENGL

2000

m

0 7 8 4 2 b 5

0520063 778

m

AWS

C5.3:2000

to determ ine what the respo nse to the inquiry should be.

Following the subcommittee’s development of the re-

spons e, the inquiry and the response are presented to the

entire com mittee for review and approval. Upon approval

by the comm ittee, the interpretation will be an of fcia l in

terpreta tion of the Society, and the secreta ry will transmit

the respon se to the inquirer and to the Welding Journal

for publication.

C4. Publication of Interpretations

All official interpretations will appear in the Welding

Journal.

C5

Telephone Inquiries

Telephone inquiries to AWS Headquarters concerning

AWS

tandards should be limited to questions of a gen-

eral nature or to matters directly related to the use of the

Stand ard. The Board of D irectors’ policy requires that all

A W S taff mem bers respond to a telephon e request for

an oficial interpretation

of

any

AWS

tandard with the

information that such an interpretation can be obtained

only through a written request. The Headquarters staff

c a n

not provide consulting services.The

staff

can, however,

refer a caller to any of those consultants whose names a re

on file at AWS Headquarters.

C6. TheAWS Technical Committee

The activities of AWS Technical Committees in re-

gard to interpretations, are limited strictly to the Interpre-

tation of provisions of standards prepared by the committee

or to conside ration of revisions to existin g provision s on

the basis of new data or technology. Neither the c omm it-

tee nor the staff is in a position to offer interpretive or

consulting services on: (1)

specific

engineering problems,

or (2) requirements of stan dards applied to fabrications

outside the scope of the document or points not specifi-

cally covered by the standard. In such cases, the inquirer

should seek assistance from a com petent engineer expe-

rienced in the particular field of interest.

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S T D - A W S C 5 . 3 - E N G L 2000 = Cl7BLi2b5

0 5 2 0 0 b L I bü9

AWS C5.3:2000

AWS List of Documents on Arc Welding and Cutting

AWS

Designation

Title

C5.1 Recornmended Practices for Plasma Ar c Welding

c5.2

Recommended Practices for Plasma Arc Cutting

0 . 3 Recommended Practices for Air Carbon Arc Gouging and Cutting

c5.4

c5.5

(25.6

c5.7

C5.10

For

ordering information, contact the AWS Order Department, American Welding Society, 550 N.W. LeJeu ne Road,

Miami, FL 33126. elephones:

800)

334-9353, 305) 443-9353, xt.

280;

AX 305) 43-7559.

Recommended Practices for Stud Welding

Recommended Practices for Ga s Tungsten Arc Welding

Recommended Practices for Gas Metal Arc Welding

Recommended Practices for Electrogas Welding

Recommended Practices for Shielding Gases for Welding and Plasma A rc Cutting

Date post:	02-Jun-2018
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