STD-AWS C3-b-ENGL 3999 111 O784265 0533378 930

Superado

AWS C3.6: 1999

An American National Standard

Specification for
Furnace Brazing

--``,``-`-`,,`,,`,`,,`---

Copyright American Welding Society

Provided by IHS under license with AWS
No reproduction or networking permitted without license from IHS

Not for Resale

STDmAWS C3.b-ENGL

Key Words-

L999

Furnace brazing,quality control,

inspection of brazed joints, brazing
materials, brazing equipment,
classification of brazed joints, brazed
joint discontinuities, nondestructive
testing, furnace brazing procedure
specification

W 07842b5 053l1379 873

AWS C3.6:1999
An American National Standard
Approved by
American National StandardsInstitute
March 11,1999

Specification for
Furnace Brazing
Supersedes ANSI/AWS C3.6-90

Prepared by
AWS Committee on Brazing and Soldering
Under the Direction of
AWS Technical Activities Committee
Approved by
AWS Board of Directors

Abstract
This specification provides minimum fabrication, equipment, material, process procedure requirements, and inspection
requirements for the furnace brazing of steels, copper, copper alloys, and heat and corrosion resistant alloys and other
materials that canbe adequately furnacebrazed. For the brazing of aluminum alloys refer to AWS C3.7, Specification for
Aluminum Brazing. This specification provides criteria for classifying furnace brazed joints based on loading and the
consequences of failure and quality assurance criteria defining
the limits of acceptability of each class. The specification
defines acceptable furnace brazing equipment, materials, and procedures, as well as the required inspection for each
class of joint.

American Welding Society

--``,``-`-`,,`,,`,`,,`---

Copyright American Welding Society

Provided by IHS under license with AWS
No reproduction or networking permitted without license from IHS

550 N.W. LeJeune Road, Miami, Florida 33126

Not for Resale

07842b5 0511380 599 R

Statement on Use of AWS Standards

--``,``-`-`,,`,,`,`,,`---

All standards (codes, specifications, recommended practices, methods, classifications, and guides) of the American
Welding Society are voluntary consensus standards that have been developed in accordance 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 state lawsand regulations, or the regulations of other governmental bodies, their provisions
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 become a part of those laws and regulations. In all
cases, these standards carry the full legal authority of the contract or other document that invokes the AWS standards.
Where this contractual relationship exists, changesin or deviations from requirements of an AWS standard must be by
agreement between the contractingparties.

International Standard Book Number: 0-87171-555-4

American Welding Society, 550 N.W. LeJeune Road, Miami, FL 33126
O 1999 by American Welding Society. All rights reserved
Printed in the United States of America
Note: The primary purpose of AWS is to serve and benefit its members. To this end, AWS provides a forum for the
exchange, consideration, anddiscussion of ideas and proposals that are relevant to the welding industry and the consensus of which forms the basis for these standards. By providing such a forum, AWS does not assume any duties to which
a user of these standards may be required to adhere. By publishing this standard, the American Welding Society doesnot
insure anyone using the information it contains against any liability arising from that use. Publication of a standard by
the American Welding Society does not carry with it any right to make, use, or sell any patented items. Users of the
information in this standard should make an independent, substantiating investigation of the validity of that information
for their particular use and the patent status of any item referred to herein.
Official interpretations of any of the technical requirements of this standard may be obtained by sending a request, in
writing, to the Managing Director Technical Services, American Welding Society, 550 N.W. LeJeune Road, Miami, FL
33126 (see Annex A). With regard to technical inquiries made concerning AWS standards, oral opinions on AWS
standards may be rendered. However, such opinions represent only the personal opinions of the particular individuals
giving them. These individuals do not speak on behalf of AWS, nor do these oral opinionsconstitute official or unofficial
opinions or interpretations of AWS. In addition, oral opinions 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 Committee on Brazing and Soldering. It must be reviewed
every 5 years and if not revised, it must be either reapproved or withdrawn. Comments (recommendations,additions, or
deletions) and any pertinent data that may be of use in improving this standard are requested and should be addressed to
AWS Headquarters. Such commentswill receive careful consideration by the AWS Committee on Brazing and Soldering
and the author of the comments will be informed of the Committees response to the comments.Guests are invited to attend
all meetings of the AWS Committee onBrazing and Soldering to express their comments verbally. Procedures for appeal
of an adverse decision concerning all such comments are provided in the Rules of Operation of the Technical Activities
Committee. A copy of these Rules can be obtained from the American Welding Society, 550 N.W. LeJeune Road, Miami,
FL 33 126.
Photocopy Rights
Authorization to photocopy items for internal, personal, or educational classroom use only, or the internal, personal, or
educational classroom use only of specific clients, is granted by the American Welding Society (AWS) provided that the
appropriate feeis paid to the Copyright Clearance Center, 222 Rosewood Drive, Danvers, MA 01923, Tel: 978-750-8400;
online: http://www.copyright.com

Copyright American Welding Society

Provided by IHS under license with AWS
No reproduction or networking permitted without license from IHS

Not for Resale

STD-AWS C3-b-ENGL 3999

07842b5 0533383 425

Personnel
AWS Committee on Brazing and Soldering

M. J. Lucas, Chair
D. W Bucholz, 1st Vice Chair
C. B. Pollock, Secretary
*A. Baldantoni
B. Barten

General Electric Aircraft Engines

OEA
American Welding Society
Hydro Aluminum Extrusions
Delphi Harrison Thermal Systems,
Division of General Motors Corporation
Amalgamated Technologies
North American Operations, General Motors Corporation
Industrial Testing Lab Services
NCC Engineering, Incorporated
Consultant
Scarrott Metallurgical Company
Alloy Ring Service
Allied Signal Aerospace
Copper Development Association, Incorporated
PraxairPyromet Group
Sandia National Laboratories
Modine Manufacturing Company
Williams Advanced Materials
General ElectricPower Generation
PraxairPyromet Group
WESGO, Incorporated
Wall Colmonoy Corporation
Daryl D. Peter and Associates
Allied Signal, Incorporated
Engelhard Corporation
Oak Ridge National Laboratories
Omni Technologies Corporation
Lucas-Milhaupt, Incorporated
Consultant
Sandia National Laboratories
Princeton Engineering Group

*R. E. Beal
S.S. Bhargava
*A. B. Cedilote

--``,``-`-`,,`,,`,`,,`---

N. C. Cole
*R. E. Cook
R. G. Fairbanks
C. E. Fuerstenau
f! K. Gupta
R. L. Hall, Jr.
M. J. Higgins
E M. Hosking
J. R. Jachna
*H. Lichtenberger
*M. Manning
C. Moyer
T. Oyama
R. L. Peaslee
*D. D. Peter
A. Rabinkin
W D. Rupert
M. L. Santella
J. L. Schuster
A. Severin
J. R. Terriff
I! Vanco
*R. W Walls
*Advisor

...

111
Copyright American Welding Society
Provided by IHS under license with AWS
No reproduction or networking permitted without license from IHS

Not for Resale

STD-AWS C3.b-ENGL 1999 II 07842b5 0511382 3b1 II

Foreword

This specification is one of a series prepared at the request of the Aerospace Industries Association and a number of
others to replace MIL-B-7883. This military specification covered all brazing processes and had become obsolete as
such processes had proliferated and the technology had become more complex.
Attempting to cover all of the diverse brazing processes in one concise, easily understood document was found to be
impossible, and therefore a series of four independent specifications on brazing were written, all in the same format.
They are AWS C3.4, Specification for Torch Brazing, AWS C3.5, Specification for Induction Brazing, and AWS C3.6,
Specification for Furnace Brazing. Torch, induction and furnace brazing of aluminum alloys are covered in AWS C3.7,
Specification for Aluminum Brazing. It was decided to subdivide the technology in this way based upon a survey of production brazing applications conducted by the AWS Committee on Brazing and Soldering. The committee is currently
working to complete a specification on resistance brazing.
The survey showed that these categories would cover the vast majority of brazing done in the United States today. An
additional document is ANSI/AWS C3.8, Ultrasonic Inspection of Brazed Joints. In the preparation of the first four
brazing specifications, it was found that no such document existed which could be referenced bythem to provide
specific criteria and requirements for the application of this important new technology to brazed joints.
Comments and suggestionsfor theimprovement of this specification are welcome.They should be sent to the
Secretary, Committee on Brazing and Soldering, AmericanWelding Society, 550 N.W. LeJeune Road, Miami, FL
33126.
Official interpretations of any of the technical requirements of the specification may be obtained by sending a request
in writing to the Managing Director, Technical Services, American Welding Society. A formal reply will be issued after
the request has been reviewed by appropriate personnel following established procedures.

iv
Copyright American Welding Society
Provided by IHS under license with AWS
No reproduction or networking permitted without license from IHS

Not for Resale

--``,``-`-`,,`,,`,`,,`---

(This Foreword is not a part of AWS C3.6:1999, Specification for Furnace Brazing, but is included for information
purposes only.)

Table of Contents
Page No.

...

Personnel ....................................................................................................................................................................
Foreword ...................................................................................................................................................................

111

iv

2. Applicable Documents
............................................................................................................................................

3. Classification of Brazed Joints ...............................................................................................................................

3.1 Method of Classification ................................................................................................................................
3.2 Class A Joints .................................................................................................................................................
3.3 Class B Joints.................................................................................................................................................
3.4 Class C Joints.................................................................................................................................................
3.5 No Class Specified .........................................................................................................................................

2
2
2
2
2
2

4. Process Requirements .............................................................................................................................................

4.1 Process Description ........................................................................................................................................
4.2 Equipment ......................................................................................................................................................
4.3 Furnace Brazing Materials .............................................................................................................................
4.4 Furnace Brazing Process Requirements .........................................................................................................
4.5 Qualification...................................................................................................................................................
4.6 Safety and Health ...........................................................................................................................................

2
2

.................................................................................................................................
5. Quality Assurance Provisions
5.1 Responsibility for Inspection .........................................................................................................................
5.2 Requirements for Compliance .......................................................................................................................
5.3 Sequence of Inspection and Manufacturing Operations ................................................................................
5.4 Required Inspections of Brazed Joints ...........................................................................................................
5.5 Acceptance Criteria........................................................................................................................................
5.6 Process Completion ........................................................................................................................................
6. Definitions ..............................................................................................................................................................

2
4
4

5
5
5
5
5
5
5
7
8
8

Annex A q u i d e l i n e s for Preparation of Technical Inquiriesfor AWS Technical Committees.................................... 9

A l . Introduction .................................................................................................................................................... 9
A2 . Procedure ....................................................................................................................................................... 9
A3 . Interpretation of Provisions of the Standard .................................................................................................. 9
A4 . Publication of Interpretations .......................................................................................................................
10
A5 . Telephone Inquiries ...................................................................................................................................... 10
A6 . The AWS Technical Committee.................................................................................................................. 10
AWS Brazing and Soldering Documents
.....................................................................................................................

V
Copyright American Welding Society
Provided by IHS under license with AWS
No reproduction or networking permitted without license from IHS

Not for Resale

11

--``,``-`-`,,`,,`,`,,`---

1. Scope ....................................................................................................................................................................... 1

= 07842b5

STD*AWS C3-b-ENGL L999

0533384 L34 W
AWS C3.6:1999

--``,``-`-`,,`,,`,`,,`---

Specification for Furnace Brazing

1. Scope

(4) ANSIIAWS A5.31, Specification for Fluxes for

Brazing and Braze Welding
(5) ANSIIAWS B2.2, Brazing Procedure and Performance Qualjcation
(6) ANSIIAWSC3.8, Recommended Practicesfor
Ultrasonic Inspection of Brazed Joints
(7) AWS Brazing Handbook
(8) ANSIIASQC 21.4, Sampling Procedures and
Tablesfor Inspection by Attributes
(9) ANSI 249.1, Safety in Welding, Cutting, andAllied
Processes
(10) AMS 2403, Plating, General Purpose
(11) AMS 2404, Plating, Electroless Nickel
(12) AMS 2424, Plating, Nickel, Low Stressed Deposit
(13) AMS 2750, Pyrometry
(14) ASTM E 230 Electromotive Force (EMF) Tables
for Standardized Thermocouples
(15) ASTM E1742, Standard Practice for Radiographic Examination
(16) ASTM E 1417, Standard Practice for Liquid Penetrant Examination
(17) ANSIINCSL 2540-1, General Requirements for
Calibration Laboratories and Measuring and Test
Equipment

This specification presents minimum fabrication and

quality requirementsfor furnace brazingmaterial such as
steels, stainless steels, nickel, nickel alloys, copper, copper alloys, and heat or corrosion-resistant materials and
other materials that can be adequately furnace brazed.
For the brazing of aluminum alloys refer to AWS C3.7,
Specification for Aluminum Brazing. The purpose of this
specification is to standardize furnace brazing
process requirements and controlbraze joint quality for all applications where braze joints of assured quality are required.
This document states minimum requirements for processes and products witha minimum of explanatory information so that sources of ambiguity are reduced. It
assigns responsibility for the ultimate quality of the
brazed product to a single organization and permits that
organization to modify requirements if appropriate to
the application. It requires proper documentation of any
such modifications. Units are rationalized conversions
from U.S. Customary Units to SI Units and my be used
interchangeably.

Document Sources:

2. Applicable Documents

American Welding Society (AWS), 550 N.W. LeJeune

Road, Miami, FL 33126

The following documents form a part of this specification, as referenced by this specification. Unless otherwise specified by the Organization Having Quality
Responsibility, the revision of these documents in force
at the time a contract
or purchase order isissued shall be
used.
(1) ANSIIAWS A2.4, Symbols for Welding, Brazing,
and Nondestructive Examination
(2) ANSIIAWS A3.0, StandardWeldingTermsand
Definitions
(3) ANSIIAWS A5.8, Specification for Filler Metals
for Brazing and Braze Welding

American Society for Quality (ASQ), 611 East Wisconsin Avenue, Milwaukee, W1 53201
American
Society
for Testing and Materials
(ASTM),100 Barr Harbor Dr., West Conshohocken, PA
19428-2959
National Conference of Standards Laboratories, 1800
30th Street; Suite 305B,Boulder, CO 80301
Society of Automotive Engineers (SAE), 400 Commonwealth Drive, Warrendale, PA 15096-0001

1
Copyright American Welding Society
Provided by IHS under license with AWS
No reproduction or networking permitted without license from IHS

Not for Resale

STD-AWS C 3 - b - E N G L
AWS C3.6:1999

recording devices i n good working order capable of

controlling the temperature of the furnace to the requirements of this specification. Furnaces shall have adequate
capacity to accomplish uniform heating of the workload
at the rate required to prevent both unacceptable thermal
distortion of the assemblies and liquation of the filler
metal. The furnace and associated equipment shall be
properly maintained in good working order.

3. Classification of Brazed Joints

3.1 Method of Classification. Furnace brazed joints are
classified in this specification based on two criteria: the
design requirements and the consequences of their failure.
It is the responsibility of the Organization Having Quality
Responsibility to evaluate these or other factors and assign the proper classification. This classification controls
which inspection methods and limits are required.

4.2.2 Temperature
Measurement
and Control
Instruments. In closed, batch-type furnaces, suitable
instrumentation and thermocouples (see 4.2.3) shall be
provided to measureand
control the temperature of
assemblies being brazed. In equipment where AMS2750
is not used in its entirety the provisions of this section
shall apply. The instrument shall be of the potentiometer
type capable of measuring, recording, and providing a
permanent record of the temperature through the entire
brazing thermal cycle. In furnaces with multiple heating
zones (i.e., preheat zone, braze zone, postheat zone),
such instrumentation shall be provided for each zone.
All instruments used to measure the temperature of
assemblies being brazed or to control furnace temperature, or both, shall have an indicated temperature accuracy range of not more than plus or minus 0.5 percent of
the maximum for which the furnace is qualified over the
entire operating range, including each furnace heat zone.
The indicated temperature accuracy of the instrument
shall be determined in accordance with the equipment
manufacturer's recommendations usinga known electromotive force input traceable to the National Institute of
Standards and Technology.'
All instruments shall be calibrated in accordance with
AMS 2750 and ANSI/NCSL 2540-1. Instruments shall
be calibrated on a regular schedule or whenever repairs
or modifications are made to them.

3.2 Class A Joints. Class A joints are those joints subjected to high stresses, cyclic stresses, or both, the failure
of which could result in significant risk topersons or property, or could result in a significant operational failure.
3.3 Class B Joints. Class B joints are those joints subjected to low or moderate stresses, cyclic stresses or
both, the failure of which could result in significant risk
to persons or property, or could result in a significant
operational failure.
3.4 Class C Joints. Class C joints are those joints subjected to low or moderate stresses, cyclic stresses or
both, the failure of which would have no significant, detrimental effect.

3.5 No Class Specified. When no class is specified on the

engineering drawing or other applicable document approved by the Organization Having Quality Responsibility, Class A requirements shall apply. However, because
of the confusion which can result, all engineering drawings referencing this specification should state the class
of the brazed joint in the braze joint symbol. Symbols
shall be in accordance with ANSI/AWS A2.4, Symbols
for Welding, Brazing, andNondestructive Examination.

4. Process Requirements

4.2.3 Workload Control Thermocouples. Workload

control thermocouples shall be of a type listed in ASTM
E 230. They shall be calibrated by comparison to a
known calibrated test instrument traceable to the National Institute of Standards and Technology at least
monthly and replaced as required.

4.1 Process Description. Furnace brazing is a process in

which assembled components, with filler metal preplaced, are loaded into the furnace. The furnace then is
purged with a neutral or reducing atmosphere, or evacuated of air, and heated to a temperature (generally above
the liquidus of the filler metal) but less than the melting
point of the base metals. The brazements are then cooled
or quenched at an appropriate rate so as to minimize distortion and produce the required properties in the filler
metal and base material. This cycle is designed to produce the melting andsolidification of the filler metal required to join the components without melting or
damaging the base metals.

4.2.4 Work ZoneControlThermocouples.

Work
zone control thermocouples shall be of a type listed in
ASTM E 230. They shall be calibrated by comparison to
a known calibrated instrument traceable to the National
Institute of Standards and Technologyat least monthly,
and replaced as required.

4.2 Equipment

1 . National Institute of Standards and Technology,Office of

Standard Reference Materials, Building 202, Room 206, Gaithersburg, M D 20899.

4.2.1 GeneralFurnaceRequirements. All brazing

furnaces shall have automatic temperature control and
--``,``-`-`,,`,,`,`,,`---

Copyright American Welding Society

Provided by IHS under license with AWS
No reproduction or networking permitted without license from IHS

2
Not for Resale

078Y2h5 0511386 T07

STDaAWS C3-b-ENGL 1999

AWS C3.6:1999

of furnaces having a work zone larger than 0.28

(10 ft). No more than 40 thermocouples shall be

m3
required to determine the temperature uniformity in the
work zone of any furnace.
The thermocouples shall be symmetrically distributed
within the work zone. Qualification shall be performed at
the highest and lowest brazing temperature at which the
furnace is used, and at intermediate temperature such
that the difference between qualification temperaturesis
not greater than 315C (600F). The temperature ofall
test and furnace control thermocouples shall berecorded
at intervals of no more than 5 minutes starting immediately after heating begins. Temperature measurement and
recording shall continue at least 30 minutes after equilibrium has been reached to determine the temperature pattern of the furnace. The resultsof the test shall be posted
at the furnace, and shall include the dateof testing, due
date of next test, the size of the work zone, and the results of the tests including the location within the work
zone of the hottest and coldest location.

4.2.5 Atmosphere Controlling Instruments

4.2.5.1
Electronic
Dewpoint
Measuring
Devices. Electronic dewpoint measuring devices shall be
calibrated in accordance with the manufacturers recommendations against reference devices traceable to the
National Institute of Standards and Technology, or equivalent. Such gages shall be calibrated before initial use
and calibrated in accordance with 4.2.2.
4.2.5.2 Vacuum Measuring Devices. Thermocouple gages shall be used to measure pressure higher than
0.13 Patorr).Suitableelectronicgagesshallbe
used tomeasurepressures of 0.13 Pa
torr), or less.
These gages shallbe so mounted as to measure the pressure within the work zone of the furnace. Suitable instruments for reading and recording the pressure within the
furnace work zone also shallbe provided. These instruments and gages shall be calibrated in accordance with
the manufacturers recommendations against reference
standards traceable to the National Institute of Standards
and Technology. Such gages shall be calibrated before
initial use and calibrated in accordance with 4.2.2.

4.2.6.2 Temperature Uniformity Requirements.

Before temperature equilibrium has been reached, no
temperature reading shall exceed the temperature for
which the furnace is being qualified by more than 14C
(25F). After temperature equilibrium has been reached,
the temperature recorded by any test thermocouple shall
not vary from theselected furnace control temperature
by
more than 14C (25F).

4.2.6Furnace Qualification. In equipmentwhere

AMS 2750 is not used in its entirety the provisions of
this section shallapply. All furnaces shall be qualified for
temperature uniformity and control prior to initial use for
production brazing. Furnaces used for brazing above
1093C (2000F) shallbe requalified at least every three
months. Furnaces used only for brazing below 1093C
(2000F) shall be requalified every six months. All furnaces shall be requalified after any repairs or alterations
to the furnace which might affect furnace temperature
control or uniformity (e.g., new heating elements, new
control thermocouple(s), burner tubes, replacement of
shielding burner tubes, etc.) Requalification is not required when the repair or alteration has previously been
documented not to affect the temperature control or uniformity of the furnace.

4.2.8 Vacuum Furnace Requirements. Vacuum furnaces shall comply with the following performance requirements. A cold and previously outgassed furnace
shall leak no more than2.6 Pa (20 x
torr) perhour
when the vacuum chamber is isolated from the pumping
system after being evacuated to 0.65 Pa (5 x 10 torr).
Less than 1.3 Pa (10 x
torr) per hour is required for
more critical applications. It shall be measured over a
time period of no less than 15 minutes. Such a leak rate
test shall be performed at least once a week,or whenever
there is reason to suspect that an unacceptable leak rate
exists. The furnace should have the capability of introducing argon, hydrogen, helium,or nitrogen if required
for rapid cooling or to backfill after evacuation to maintain a partial pressure if required to prevent sublimation
of elements from the brazing fillermetal.

4.2.6.1 Furnace Qualification Procedure. Temperature uniformity tests shall be conducted with a furnace load representative of production parts, material,
racks, and using a typical production atmosphere or
vacuum level. The test shall be conducted using new or
calibrated thermocouples. The potentiometric
measuring
equipment shallmeet the requirements of 4.2.2.
Instruments usedto control the furnace during production brazing shall not be used to monitor the qualification thermocouples. Aminimum of two thermocouples
shall be used to determine the temperature uniformity of
furnaces having a work zone volume of 0.28 m3 (10 ft3),
or less. A minimum of nine thermocouples or one thermocouple per 0.71 m3 (25 ft3) of working zone, whichever is greater, shall be used to detem-he the uniformity
3
Copyright American Welding Society
Provided by IHS under license with AWS
No reproduction or networking permitted without license from IHS

Not for Resale

--``,``-`-`,,`,,`,`,,`---

4.2.7AtmosphereFurnaceRequirements.
Atmosphere controls shall be suitable for the intended purpose
and in good workingorder. The gas supplyand purification system shall be capable of supplying atmosphere
gases in accordance with the approved brazing procedure
specification (see 4.4.7).

STD.AWS C3.b-ENGL
AWS C3.6:1999

4.2.9Fixtures. When required, furnace brazing fixtures shall be made of suitable materials which will not
contaminate the furnace or workload either upon contact
or by vaporization. Fixtures shall be designed, built, and
maintained to provide adequate support of assemblies,
maintain proper braze joint clearance, accommodate
thermal expansion, and not adversely affect mass load
and uniformity. Appropriate conditioning of the fixtures
is required to prevent or minimize brazing of the fixtures.
--``,``-`-`,,`,,`,`,,`---

removed, as required, prior to final cleaning to permit

proper assembly and filler metal flow.

4.4.2 Nickel Plate. Nickel plating is recommended on

the brazed jointareas of stainless, corrosion, or heatresistant steels having equal or greater percentage by
weight of the following alloying elements:
(1) Titanium--0.40%
(2) Aluminum4.40%
(3) Titanium plus aluminum--0.70%
Nickel plate 0.01 to 0.02 mm (0.0004 to 0.0008 in.)
thick shall be applied in accordance with AMS 2424 or
AMS 2403. When the braze temperature is below 815C
(1500F) AMS 2404 for electroless nickel plate may be
used. It shall extend 2.5 mm (0.10 in.) minimum beyond
the brazed joint area indicated by the brazing symbol on
the engineering drawing unless part configuration does
not permit this allowance. l n addition, nickel plate may
be specified by the Organization Having Quality Responsibility to cover any area, or the entire surface, of details
or assemblies at its discretion. When the drawing or purchase documents do not specify localized plating, the
parts may be completely plated.

4.3 Furnace Brazing Materials

4.3.1 Filler Metal. Filler metal shall be specified by
the engineering drawing or accompanying documents
and shall meet the requirements of ANSI/AWS A5.8, unless otherwise specified by the engineering drawing or
accompanying document. There are filler metal/base
metal combinations that can cause severe service problems in certain circumstances, e.g., nickel-base alloys
brazed with silver-bearing filler metals, and iron-base alloys brazed with copper-base filler metals containing
phosphorous. Care, therefore, should be used to assure
that the filler metal selected ismetallurgically compatible
with the base metal.

4.4.3 Joint Clearance. Joint clearance between mating surfaces of joints to be furnace brazed, if not otherwise specified by the engineering drawing, shall be
controlled by the assembly procedures so that proper
joint clearance is provided at the brazing temperature.
When one of the mating surfaces is straight-line knurled
in the direction of filler metal flow into the joint, a lineto-line fit is permitted. The depth of such knurling shall
not exceed 0.13 mm (0.005 in.) below the original surface. Suggested joint clearances for typical materials
may be found in the AWS Brazing Handbook, Table 2.1.

4.3.2 Fluxes. Fluxes may be used in combination with

controlled atmospheres, other than in vacuum, only when
specified on the qualified brazing procedure specification
(see 4.4.7). Fluxes shall conform to the requirements of
ANSI/AWS A5.31, Specification for Fluxes for Brazing
und Braze Welding.
4.3.3CleaningMaterials. Cleaning materials shall
leave no residues which interfere with the wetting or
flow of the filler metal, e.g., aluminum oxide,zirconia, or
silica sand shallnot be used on components to be brazed.
Chemical cleaning solutions which are detrimental to the
base metal shall not be used.

4.4.4 Tack Welding. When tack welding is required

to maintain proper positioning of components, tack weld
size, location, and filler metal shall be specified on the
engineering drawing, or in writing by the Organization
Having Quality Responsibility. Tack welds shall be applied with adequate inert gas shielding per the approved
welding procedure to assure that oxide contamination of
the braze joint surfaces doesnot occur.

43.4 FurnaceAtmosphereGases.
Furnace atmosphere gases shall be compatible with the filler and base
metals and suitablefor the particular application.
4.3.5 Braze Stopoff. Braze stopoff, if used, shall be
suitable forthe intended purpose and compatible with the
base metal(s), filler metal, and furnace atmosphere. In
certain specialized applications, residues from stopoff
materials can produce unacceptable contamination of the
product. If any doubt exists, permission of the Organizution Having Quality Responsibility should be obtained
prior to use.

4.4.5Application of Filler Metal. The filler metal

specified by the engineering drawingmay be applied as a
paste mixture, slurry, wire, foil, cladding (braze sheet)or
preformed shapes, as specified in the approved brazing
procedure specification. Filler metal shall be applied to
one side of the joint only, so that it flows through the
joint by capillary action in order to facilitate visual inspection. Filler metal placement between the joint surfaces of Class A and Class B joints shall be permitted
only when permitted by the engineering drawing or with
the prior written approval of the Organization Having

4.4 Furnace Brazing Process Requirements

4.4.1Cleaning. Components to be furnace brazed
shall be free of oil, grease, paint, oxides, dirt, scale, or
other foreign substances that can interfere with the brazing process or contaminate the braze joint. Burrs shall be
4
Copyright American Welding Society
Provided by IHS under license with AWS
No reproduction or networking permitted without license from IHS

Not for Resale

STD-AWS C3.b-ENGL

07842b5 05LL388 88T

L999

II
AWS C3.6:1999

5. Quality Assurance Provisions

Quality Responsibility, or if ultrasonic inspection or another approved inspection procedure per 5.4.1.4 is performed to assure proper metallurgical bonding between
the filler and base metals. After filler metal application,
assemblies shall be protected from contamination by
suitable means.

5.1 Responsibility for Inspection. Unless otherwise

specified in the contract or purchase order,the organization performing a brazing operation is responsible for all
inspection of the brazed joints. This requirement includes a system of quality control and documentation
which assures and can attest that all required operations
and procedures were performed. Suppliersmay use their
own facilities or any other facility acceptable to the Organization Having Quality Responsibility for the inspection of the final product. However, the Organization
Having Quality Responsibility shall retain the right to
perform or witness the required tests or to perform any
other tests necessary to assure that the brazed assemblies
conform to the requirements of this specification and the
engineering drawing.

4.4.6 Application of Stopoff.Braze stopoff materials

shall be applied in quantities and locations, as specified
in the approved brazing procedure specification, to control filler metal flow in order to meet the engineering
drawing requirements. It shall not be applied in such a
manner that the braze joint surfaces
or the filler metal are
contaminated.
4.4.7ProcessCompletion. Rebraze cycles shall be
permitted only to a brazing procedure specification
meeting the requirements of 4.5 and as specified in 5.6.

5.2 Responsibility for Compliance. All products shall

meet all requirements of this specification except where
deviation is specifically approved, in writing, by the Organization Having Quality Responsibility, or is part of
the engineering drawing. The braze inspections required
shall become a part of the contractors overall inspection
system or quality program. The absence of any inspection requirements in this specification shall not relieve a
contractor of the responsibility of assuring that all products or supplieswhich the contractor produces under this
specification meet all contractual obligations. The use of
inspection sampling systems (see5.4.2) does not authorize the shipment of known defective material nor does it
obligate any person or organization to accept defective
material.

4.4.8 Postbrazing Operations. Assemblies shall be

cooled after brazingin such amanner that cracking of the
filler or base metals does not occur and residual stresses
are minimized. Postbraze heat treatments, or combined
brazing and heat treating cycles, if required, shall be performed per the engineering drawing. If required, flux or
stopoff residues shallbe removed by suitable means.
4.5 Qualification. Brazing and related procedures and
equipment shall be qualified in accordance with AWS
B2.2, or as required by the Organization Having Quality
Responsibility. All qualifications shall be documented
and approved in writing by the Organization Having
Quality Responsibility prior to their use. If multiple
braze cycles are required for product fabrication, all cycles shall be so qualified, documented, and approved.
Prior to use, any modification of the approved procedure(s) shall be approved in writing by the Organization
Having Quality Responsibility.

5.3 Sequence of Inspection and ManufacturingOperations. Furnace brazed joints may be inspected at the assembly or subassembly level, provided the entire joint is
accessible for inspection. Parts requiring postbraze heat
treatment shallbe inspected after heat treatment has been
completed, unless otherwise specifiedon the engineering
drawing. When brazed joints are inspected in process
prior to machining of joint edges, reinspection shall be
required after machining to assure that the brazed joint
has not been damaged in the machining operations. Inspection shouldbe done after postbraze cleaning.

4.6 Safety and Health. Torch brazing fluxes and filler

materials, particularly those containing cadmium, give
off hazardous fumes during the brazing cycle.It is mandatory that torch brazing operations be properly and adequately ventilated or that operators be provided with
adequate breathing apparatus, or both, as required to assure that all relevant federal, state, and local government
safety and health requirements are met. In addition, there
are other hazardsinvolved in torch brazing, suchas those
relating to the use of corrosive fluxes, potentially explosive gases, and hot surfaces. Refer to ANSI 249.1, Safety
in Welding, Cutting, and Allied Processes, for information on these and other safety and health problems which
must be controlled during torch brazing. Information on
hazards associated with materials used in the brazing
process may be found in the Material Safety Data Sheets
(MSDS), available from the manufacturer.
--``,``-`-`,,`,,`,`,,`---

Copyright American Welding Society

Provided by IHS under license with AWS
No reproduction or networking permitted without license from IHS

5.4 Required Inspections of Brazed Joints. All brazed

joints shall meet the acceptance criteriagiven in 5.5.
5.4.1 Class A and Class B Brazed Joints. Class A
and Class B brazed joints, except as specified in 5.4.1.3
and 5.4.1.4, shall be either radiographically or ultrasonically inspected to determine the area of the joint surfaces
actually brazed and to detect internal discontinuities.
Choice of process is optional, except for the criteria
given in 5.4.1.1 and 5.4.1.2. Acceptance criteria shall be
5
Not for Resale

AWS C3.6:1999

as specified in 5.5, unless otherwise specified on the engineering drawing.

(1) Class A joints shall be pressure tested at an internal pressure and by procedures specified in writing by
the Organization Having Quality Responsibility. No
measurable leakage shallbe allowed. They shall then be
helium leak tested in accordance with a procedure outlined by the Organization Having Quality Responsibility,
and leakage ofnot more than 3.0 x
cchecond shall
be detected with a suitable detectorin good working condition calibrated as specifiedby its manufacturer.
(2) Class B joints shall be pressure tested at an internal pressure and by procedures specified in writing by
the Organization Having Quality Responsibility. No visually detected leaks shall be allowed.
Internal pressure test fixtures and devices shall be suitable for the intended purpose and shall be adequately
shielded to prevent injury to persons in case of catastrophic failure duringpressure testing.

5.4.1.1RadiographicInspection.
Radiographic
inspection shall be performed in accordance with ASTM
E 1742, Standard Practice for Radiographic Examination. Brazed jointsshall be radiographically inspected
only when specified in the engineeringdrawing, or when
the following configurationand process requirementsare
met
(1) The clearance between the joint surfaces at assembly should be two percent or more of the total thickness of the base metals at the joint. In cases where the
joint clearance is less than 2 percent of the thickness of
the base metals, the radiographic technique shallbe demonstrated to have adequate sensitivityand be approved by
the Organization Having Quality Responsibility.
(2) The configuration of the assembly must permit
proper film placement.
(3) Filler metal shall have entered the joint proper by
capillary action during the braze cycle, i.e., no filler
metal was preplaced between the joint faces priorto the
brazing heat cycle. This does not preclude the preplacement of filler metal adjacent to the joint faces or in slots
machined within the joint area.
Ultrasonic inspection shallbe required if one or more
of these requirements are not met, except as specified in
5.4.1.4.

5.4.1.4 Alternate Inspection Techniques Certain

specialized brazed components maynotbe inspectable
by radiographic or ultrasonictechniques andmay be
unsuitable for leak or pressure testing in accordance with
5.4.1.3.
In such cases, alternate inspection techniques and acceptance limits shall be as specified in writing by the
Organization Having Quality Responsibility. That organization is responsible for the suitability for service of
the final product and of the selected inspection techniques to verify the suitability of the brazed joints. If no
such special inspection techniques and acceptance limits
have been specified in writing, all requirements of this
specification shallbe met.

5.4.1.2 Ultrasonic Inspection. Ultrasonic inspection shall be performed in accordance with ANSI/AWS
C3.8, Recommended Practice for Ultrasonic Inspection
of BrazedJoints. Ultrasonic inspection shall only be performed when all of the following configuration and processcriteriaare met. Radiographic inspection shall be
required when one or more of these criteria are not met,
except as specifiedin 5.4.1.4.
(1) The surface through which the sonic pulse enters
the material shall be parallel to the joint surfaces, and the
part must be processed so that filler metal runover onto
this surface is removed prior to ultrasonic inspection.
(2) A suitable ultrasonic reference standard shall be
available. It shall be identical to the assemblies it represents as to the joint configuration,base metal(s), joint
clearance, and filler material. It shall have defects of
known size and location suitable for calibratingthe ultrasonic apparatus.
(3) Ultrasonic facsimiles may be requiredat the discretion of the Organization Having Quality Responsibility.

5.4.2 Sample Inspection Plans

5.4.2.1 Class C joints may be inspected using sample plans in accordance with ANSI/ASQC 21.4, Sampling Procedure and Tablesfor Inspection by Attributes,
Inspection Level 11, AQL 2.5, using single sample plan
for normal inspection.
5.4.2.2 Class B joints maybe inspected using a
sample plan in accordance with ANSVASQC 21.4, as in
5.4.2.1, only with the written permission of the Organization Having Quality Responsibility and if both of the
following criteriaare met:
(1) Sampling techniques are based upon the assumption that all of the products in a given batch or lot are
identical. Proof must therefore be provided that the entire
process, including the preprocessing of the components
from which the assemblies were made, was controlled
and that all assemblies within one lot are from one identically processed population. Such proof shall be presented in writing to the Organization Having Quality
Responsibility as a precondition to the granting of permission for sampletesting; otherwise the use of sampling

5.4.13 Leak and Pressure Testingof Class A and

Class B Joints. If specified on the engineering drawing or
approved in writing by the Organization Having Quality
Responsibility, pressure and leak testing to the following
requirements may be substituted for radiographic and
ultrasonic inspection of Class A and Class B joints:
--``,``-`-`,,`,,`,`,,`---

6
Copyright American Welding Society
Provided by IHS under license with AWS
No reproduction or networking permitted without license from IHS

Not for Resale

AWS C3.6:1999

(1) Class A-Maximum size 2.3 mm (0.090 in.) with

a total accumulated length less than 10 percent of fillet
length.
(2) Class &Maximum size 2.3 mm (0.090 in.) with
a total accumulated length less than 25 percent of fillet
length.
(3) Class C-Maximum size 3.1 mm (0.120 in.) with
a total accumulated length less than 50 percent of fillet
length.

techniques shall not be approved, and 100 percent inspection is required.

(2) No operation critical to the quality of the brazed
joint shall be directly dependentupon the skill or care of
an operator, except when a written recordof the actual
process variables controlled by the operator is automatically produced.

5.4.23 Class A Joints. Class A Joints require inspection of every unit. No sample plans shall be used.

5.5.1.2 Cracks. Cracks areunacceptable.

5.4.2.4 Lot Size and Sampling. When applicable

(see 5.4.2.1 and 5.4.2.2), a random sample shall be
selected from each inspection lot in accordance with
ANSVASQC Z1.4, Sampling Proceduresand Tablesfor
Inspection by Attributes, AQL 2.5, and inspected in accordance with this specification. Lot sizes for purposes
of sampling shall consistof all brazed parts of the same
design or kind, manufactured by the same process from
similar details, prepared by the same procedures during
one continuous period and submitted for acceptance at
the sametime.

5.5.1.3 Erosion. Any evidence of braze filler erosion of the exposed base metal surfaces is unacceptable,
if the erosion of either member exceeds5 percent of the
thickness for Class Aand 1.5 percent for Class B or Class
C of the thinnest component of the brazed joint.
5.5.1.4 Failure to Melt. Failure of the filler metal
to melt completely is unacceptable.
5.5.1.5EdgeVoids. Voids which are continuous
across the joint between any two opposite joint edges
are
unacceptable for Class A and Class B. Through voids are
acceptable for Class C.

5.4.3 Additional Nondestructive Tests

5.4.3.1 Fluorescent ordye penetrant inspection
techniques in accordance with ASTM E 1417, Standard
Practice for Liquid Penetrant Examination, should only
be used on assemblies where the brazed joint has been
subjected to machining stresses to assure that the joint
has not been damaged in machining. These inspection
techniques arenot suitable for the inspection of braze fillets because they routinely give false results,

5.5.1.6BrazeFillerPenetration.
If the edge of
the joint opposite that to which the filler metal is applied
is visible after brazing, filler metal shall be present at that
edge of the joint. This requirement shall not apply in
cases where the edge of the joint opposite the edge to
which filler material is applied is not accessible for inspection, dueto the configuration of the assembly.
5.5.1.7 Flux or Flux Residue. Evidence of flux or
flux residue is unacceptable.

5.4.3.2AdditionalTests. Additional nondestructive examination may be specified by the Organization

Having QualityResponsibility.

5.5.1.8Quality
of Workmanship. Quality of
workmanship shall be such that the assemblies are suitable for the intended purpose and that surfaces are freeof
excess braze filler material which could interfere with
later operations orthe function of the product.

5.4.3.3 Destructive Test of Assemblies or Samples. Destructive test of assemblies or samples shall be
performed as required for process qualification or corrective action. Destructive testing of samples or sample
parts shall not be substituted for any nondestructive examination required by this specification except as part of
an inspection procedure complyingwith 5.4.1.4.

5.5.2 Internal Discontinuities

5.5.2.1 Class A Joints. Radiographic film or ultrasonic facsimiles of Class A joints shall show the total
measured void, or unbonded area, of the joint does not
exceed 15 percent of the total joint area. The size of the
largest void or unbonded area as measuredparallel to the
joint width shall not exceed 60 percent of the total joint
width. Any such area which is wider than 40 percent of
the width of the joint, shall extend no closer to either
edgL of the joint than 20 percent of the joint width.

5.5 Acceptance Criteria. Unless otherwise specified by

the engineering drawingor document referenced by it,
the following arethe minimum acceptance criteria for inspection of brazed joints. Any assembly failing to meet
these minimum requirements shallbe rejected.
5.5.1 External Discontinuities
5.5.1.1PinholesandVoids.
Pinholes, voids, or
filler metal skips are allowed provided they shall not
exceed the following limits. Imperfections of less than
0.38 mm (0.015 in.) are uninterpretable and are not considered as defects.
--``,``-`-`,,`,,`,`,,`---

Copyright American Welding Society

Provided by IHS under license with AWS
No reproduction or networking permitted without license from IHS

5.5.2.2 Class B Joints.Radiographic film or ultrasonic fxsimilesof Class B joints shall showthat the total
measured void, or unbonded area, of the joint does not
exceed 25 percent of the total joint area. Thewidth of the
7
Not for Resale

S T D = A W S C3.h-fNGL

L999

9 07842b5 0511391 374 9

AWS C3.6:1999

brazing procedure specification (BPS). A document

specifying the required brazing variables for a specific
application.

largest void, as measured parallel to the joint width shall

not exceed 70 percent of the total joint width. Any such
area which is wider than 60 percent of the width of the
joint, shall extend no closer to either joint edge than 15
percent of the joint width.

defect. A discontinuity or discontinuities that by nature

or accumulated effect (for example total crack length)
render a part or product unable to meet minimum applicable acceptance standards or specifications. The
term designates rejectability. See also discontinuity
and flaw.

5.5.2.3 Class C Joints. No internal inspection

requirements.
5.6 Process Completion.Brazed joints may be reworked
by brazing to the original, qualified brazing procedure
specification without the specific, written
approval of the
Organization Having Quality Responsibility, unless otherwise specified by that organization. Additional brazing
filler metal, of the same type used in the original procedure, may be used. If, after having been rebrazed twice,
the assembly still is not acceptable, or if a brazing process or filler metal other than that approved by the qualified procedure is to be used, or if disassembly of the
brazed assembly is required, prior written approval of the
procedures to be used shall be obtained from the Organization Having QualityResponsibility. If it is necessary to
change the brazing process or filler metal to accomplish
the rework, the new procedure shall be qualified as specified in 4.5.

discontinuity. An interruption of the typical structure of

a material, such as a lack of homogeneity in its mechanical, metallurgical, or physical characteristics. A
discontinuity is not necessarily a defect. See also defect and flaw.
flaw. An undesirable discontinuity. Seealso defect.
joint dimensions. The joint length is the greater of the
two dimensions of the joint parallel to the joint surfaces. The jointwidth is the lesser of these two dimensions of the joint. Clearance between the joint faces is
the third dimension to be considered.
lack of bond or unbond. A condition in a brazed joint
where although filler metal is present between the
joint faces, the filler metal does not adhere or form a
metallurgical bond with the base metal. It most commonly occurs when filler metal is preplaced between
contaminated joint faces. In many cases, it is only
nondestructively detectable by ultrasonic inspection.

6. Definitions
Terminology related to this specification is included
i n this section. Additional terms may be found in
ANSIIAWS A3.0, Standard Welding Terms and Definitions, Including Terms for Brazing, Soldering, Thermal
Spraying, and Thermal Cutting.

Organization Having Quality Responsibility. The organization responsible to the ultimate user of the
product for the quality of the product and its suitability for the intended use. This will usually be the
manufacturer and marketer of the final product in
commercial business and the prime contractor in government procurement. Although such organizations
may subcontract brazing and related operations to
others, they cannot delegate the ultimate responsibility for the service suitabilityof the product to those or
any other operations.

braze joint. The total area,as defined by the engineering

drawing, of the faying surfacesto be joined by brazing
and the fillets which form at the edges of that area.
braze joint proper. The total area, as defined by the engineering drawing, of the faying surfacesto be joined
by brazing, excluding any fillets which form at the
edges of that area.
braze symbol.The symbol on the engineering drawing
designating the location, class, and configuration of
the brazed joint. Such symbols shallbe in accordance
with the latest edition of ANSI/AWS A2.4, Standard
Symbols for Welding, Brazing, and Nondestructive
Examination.

surface porosity. A roughened or spongy appearance or

open pores on the surface of the braze fillet. Such
pores are not sharply linear or crack-like in shape. It is
confined to the fillet and does not progress into the
braze joint proper.

braze wetting. Filler metal should be smooth, adherent,

and exhibiting no evidence of repulsion of the filler
metal by the base metal surface.

void. Any area of the braze joint proper which is not

completely filled with filler material.

8
Copyright American Welding Society
Provided by IHS under license with AWS
No reproduction or networking permitted without license from IHS

--``,``-`-`,,`,,`,`,,`---

Not for Resale

STD-AWS C3.b-ENGL

0784265 05IIII392 200

L997

Annex A
Guidelines for Preparationof Technical Inquiries for
AWS Technical Committees
(This Annex isnot a part of AWS C3.6:1999, Specificationfor Furnace Brazing, but is included for informationpurposes only.)

Al. Introduction

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.

The AWS Board of Directors has adopted a policy

whereby all official interpretations of AWS standards
will be handled in a formal manner. Under that policy, all
interpretations are made by the committee that is responsible for the standard. Official communication concerning an interpretation is through the AWS staff member
who works with that committee. The policy requires that
all requests for an interpretation be submitted in writing.
Such requests will be handled as expeditiously as possible but due to the complexityof the work and the procedures that must be followed, some interpretations may
require considerabletime.

A2.2 Purpose of the Inquiry. The purposeof the inquiry

must be stated in this portion of the inquiry. The purpose
can be either to obtain an interpretation of a Standard requirement, or to request the revision of a particular provision in the Standard.

A2.3 Content of the Inquiry. The inquiry should be

concise, yet complete, to enable the committeeto quickly
and fully understand the point of the inquiry. Sketches
should be used when appropriate and all paragraphs, figures, and tables (or the Annex), which bear on the inquiry must be cited. If the point of the inquiry is to obtain
a revision of the Standard, the inquiry must provide technical justification forthat revision.

A2.Procedure
All inquiries must be directed to:

A2.4 Proposed Reply. The inquirer should, as a pro-

Managing Director, Technical Services

American Welding Society
550 N.W. LeJeune Road
Miami, FL 33126

posed reply, state an interpretation of the provision that is

the point of the inquiry, or the wording for a proposed
revision, if that is what inquirer seeks.

All inquiries must contain the name, address, and affiliation of the inquirer, andthey must provide enough information for the committee to fully understand the point
of concern in the inquiry. Where that point is not clearly
defined, the inquiry willbe returned for clarification.For
efficient handling, all inquiries should
be typewritten and
should also be in the format used here.

A3. Interpretation of Provisions of the

Standard
Interpretations of provisions of the Standard aremade
by the relevant AWS Technical Committee. The secretary of the committee refers all inquiriesto the chairman
of the particular subcommittee that has jurisdiction over
the portion of the Standard addressedby the inquiry. The
subcommittee reviews the inquiry and the proposed reply

A2.1 Scope. Each inquiry must address one single provision of the Standard, unless the point of the inquiry
9
Copyright American Welding Society
Provided by IHS under license with AWS
No reproduction or networking permitted without license from IHS

Not for Resale

--``,``-`-`,,`,,`,`,,`---

AWS C3.6:1999

STD-AWS C3.h-ENGL

L999

I07842b5 0511393 L47 D

AWS C3.6:1999

to determine what the response to the inquiry should be.

Following the subcommittees development of the response, the inquiry and the response are presented to the
entire committee forreview and approval. Upon approval
by the committee, the interpretation will be an oficial interpretation of the Society,and the secretary will transmit
the response to the inquirer and to the Welding Journal
for publication.

an official interpretation of any AWS Standard with the

information that such an interpretation can be obtained
only through a written request. The Headquarters Staff
can not provide consulting services. The staff can, however, refer a caller to any of those consultants whose
names are on file at AWS Headquarters.

A6. The AWS Technical Committee

A4. Publication of Interpretations

The activitiesof AWS Technical Committees in regard

to interpretations, are limited strictly to the Interpretation
of provisions of Standards prepared by the Committee or
to consideration of revisions to existing provisionson the
basis of new data or technology. Neither the committee
nor the Staff is in a position to offer interpretive or consulting serviceson: (1) specific engineering problems,or
(2) requirements of Standards applied to fabrications outside the scope of the document or points not specifically
covered by the Standard. In such cases, the inquirer
should seek assistance from a competent engineer experienced in the particular field of interest.

All oficial interpretations will appear in the Welding

Journal.

A5. Telephone Inquiries

Telephone inquiriesto AWS Headquarters concerning
AWS Standards should be limited to questions of a general nature or to matters directly related to the use of the
Standard. The Board of Directors Policy requires that all
AWS Staff members respond to a telephone request for

--``,``-`-`,,`,,`,`,,`---

10
Copyright American Welding Society
Provided by IHS under license with AWS
No reproduction or networking permitted without license from IHS

Not for Resale

STD-AWS C3-b-ENGL 1779

0784265 0531374 083

AWS C3.6:1999

AWS Brazing and Soldering Documents

AWS Designation
ANSI/AWS A2.4 Standard Symbols

for Welding, Brazing, and Nondestructive Examination

ANSI/AWS A3.0

Standard Welding Terms and Definitions, Including Terms for Brazing, Soldering, Thermal Spraying,
and Thermal Cutting

ANSI/AWS A5.8

Specification for Filler Metals for Brazing and Braze Welding

ANSI/AWS A5.31 Specification for Fluxes for Brazing and Braze Welding
BRH

Brazing Handbook, 4th Edition

SH

Soldering Handbook

ANSI/AWS B2.2 Specification

of Brazing Procedure and Performance Qualification

ANSVAWS C3.2 Standard

Method for Evaluating the Strength of Brazed Joints in Shear, Butt Tension, and 4-Point
Bending (Short Time Shearand Tensile, Creep Strength,and Stress Rupture)
ANSI/AWS C3.3

Recommended Practices for the Design, Manufacture, and Inspection of Critical Brazed Components

AWS C3.4
Specification
for
AWS C3.5
Specification
Induction
for

Torch Brazing
Brazing

AWS C3.6
Specification
for

Furnace Brazing

AWS C3.7
Specification
for

Aluminum Brazing

ANSI/AWS C3.8

Recommended Practices for Ultrasonic Inspection of Brazed Joints

For ordering information, contact the AWS Order Department, American Welding Society, 550 N.W. LeJeune Road,
Miami, FL 33126. Telephones: (800) 334-9353, (305)443-9353, ext. 280; FAX (305) 443-7559.

--``,``-`-`,,`,,`,`,,`---

Copyright American Welding Society

Provided by IHS under license with AWS
No reproduction or networking permitted without license from IHS

11
Not for Resale