ČSN EN ISO 13585 - Tvrdé pájení - Kvalifikační zkouška páječů a operátorů tvrdého pájení

3.15 test specimen

part or portion cut from the test piece (3.14) in order to perform specified destructive testing

[SOURCE: ISO/TR 25901-1:2016, 2.2.1.6]

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Symbols and abbreviated terms

t

material thickness

L

overlap length

D

outside pipe diameter

T

product type pipe

P

product type plate

BJ

butt joint

LJ

lap joint

TJ

T-joint

FF

face fed

PP

pre-placed

H

horizontal flow

VU

vertical up flow

VD

vertical down flow

Where the full wording is not used, the symbols listed above and brazing process reference numbers in Clause 1 shall be used when completing the qualification test certificate (see Annexes B and C).

Essential variables and range of qualification

General

The qualification of brazers, (see 5.3) and brazing operators, (see 5.4) is based on essential variables in accordance with Table 1. For each essential variable, a range of qualification is defined and brazing outside that range of qualification requires a new qualification test.

Table 1 — Essential variables for brazer and brazing operator qualification

Essential variable

Brazer

Brazing operator

Brazing process number in accordance with ISO 4063:2009

X

X

Product type: T or P

X

—

Type of joint: BJ, LJ or TJ

X

—

Parent material group(s) in accordance with Annex E

X

—

Brazing filler metal classification in accordance with ISO 17672

X

—

Brazing filler application, FF or PP

X

X

Dimensions: t, D, L

X

—

Filler metal flow direction: H, VU or VD

X

—

Type of equipment

—

X

NOTE There can be other variables that the manufacturer deems to be essential in certain applications, e.g. constraint on access for the torch, purging gas, etc., which need separate qualification (see Annex D).

The brazer or brazing operator who undertakes the brazing procedure test satisfactorily in accordance with this document is qualified provided that the relevant testing requirements of this document are met.

Brazing process

Each qualification test qualifies only one brazing process (see Clause 1). A change of brazing process requires a new qualification test.

When applicable, the furnace atmosphere is limited to the same type of atmosphere, e.g. reducing or inert, carburizing or decarburizing, and hydrogen or disassociated ammonia, as used in the test.

For brazing processes where fuel gases apply, the qualification is limited to the same type of fuel gas and flame as used in the test.

Brazer qualification

Product type

Manual brazing of one product type qualifies for other product types in accordance with Table 2.

Table 0\IF >= 1 "A." 2 — Range of qualification for product type

Dimensions in millimetres

Product type for test piece

Range of qualification

Plate

Plate and pipe

Pipe D ≤ 100

Pipe

Pipe D > 100

Pipe and plate

Type of joint

Range of qualification for type of joint is given by Table 3.

Table 0\IF >= 1 "A." 3 — Range of qualification for type of joint

Type of joint in test piece

Range of qualification

Butt joint

Butt joint

Lap joint

Lap joint

T-joint

T-joint

Parent material group(s)

In order to minimize the number of brazer qualification tests, parent materials are assigned to M-number groupings (see Annex E).

The parent material used in the brazer qualification test qualifies the brazer for brazing of all other parent materials within the same M-number grouping (see Table 4).

Parent materials that do not appear in Annex E, require separate qualification and only qualify that material.

Table 0\IF >= 1 "A." 4 — Range of qualification for parent material

Test piece material

(see Annex E)

Range of qualificationa,b

100, 110, 120, 170

100, 110, 120, 170

130, 140, 150, 160, 180

130, 140, 150, 160, 180

200, 210, 220

200, 210, 220

300, 310, 320, 330, 340, 350, 360

300, 310, 320, 330, 340, 350, 360

400, 410, 420, 430

400, 410, 420, 430

500

500

600

600

700

700

800

800

a For a test piece material used for brazer qualification, the brazer is qualified to braze all materials and all combinations of materials given in the same row.

b When test piece material from two rows are used for brazer qualification, the brazer is qualified to braze all material combinations in each row and combinations between those rows.

Filler metals and brazing filler application

The brazing filler metal type, based on its class in accordance with ISO 17672 or other standards that provide equivalent technical conditions, qualifies other filler metal types within the same class.

One filler metal form (for example from preformed ring to paste) only qualifies for the same form.

A test with a flux classified in accordance with ISO 18496, or other standards that provide equivalent technical conditions, only qualifies for brazing within that same classification.

The brazing filler metal application qualifies for other filler metal applications in accordance with Table 5.

Table 0\IF >= 1 "A." 5 — Range of qualification for brazing filler application

Test piece brazing filler application

Range of qualification

Face fed

Face fed, Pre-placed

Pre-placed

Pre-placed

NOTE Face fed”, also known as “applied to the mouth of the joint”, can be manually or mechanically fed while brazing.

Dimensions

The brazer qualification test of brazed joints is based on the material thickness, outside pipe diameter and overlap length. The ranges of qualification are specified in Table 6.

For dissimilar material thicknesses of test pieces, the range of qualification is based on the thickness of each plate (or pipe).

It is not intended that material thicknesses or outside pipe diameters should be measured precisely, but rather the general philosophy behind the values given in Table 6 should be applied.

For test pieces of different outside pipe diameters and parent material thicknesses, the brazer is qualified to:

— the larger diameter and below (see Table 6);

— twice the larger parent material thickness and below (see Table 6).

Table 0\IF >= 1 "A." 6 — Range of qualification for dimensions

Dimensions

Test piece

Range of qualification

Material thickness, t (mm)

t

≤2t

Outside pipe diameter, D (mm)a

D

≤D

Overlap length, L (mm)a

L

≤1,25L

NOTE If material thicknesses differ (see Figure F.5), the lower limit is based on the thinnest and the upper limit is based on the thickest thickness.

a If applicable.

Filler metal flow direction

The brazing of one filler metal flow direction qualifies for other flow directions in accordance with Table 7.

For personnel qualification, an angular deviation of maximum ±15° from filler metal flow positions applies.

Table 0\IF >= 1 "A." 7 — Range of qualification for filler metal flow direction

Illustrations

Filler metal flow direction of the test piece

Range of qualification

Horizontal flow

Horizontal flow and vertical down-flow

Vertical down-flow

Vertical down-flow

Vertical up-flow

All flow directions

Brazing operator qualification

Type of equipment

If mechanized or automatic brazing is used for the test, the range of qualification is limited to the brazing process and type of equipment only (see 6.2).

Filler metals and brazing filler application

If mechanized or automatic brazing is used for the test, the range of qualification is limited to the method of brazing filler application in accordance with Table 5.

Examination and testing

Supervision

The brazing of test pieces shall be witnessed by the examiner or examining body. The testing shall be verified by the examiner or examining body.

The test pieces shall be marked with the identification of the examiner and the brazer before brazing starts.

The examiner or examining body may stop the test if the brazing conditions are not correct or if it appears that the brazer or brazing operator does not have the skill to fulfil the requirements.

Brazing conditions

The qualification test of brazers and brazing operators shall follow a pBPS or BPS prepared in accordance with ISO 17779. The brazing time for the test piece shall correspond to the working time under usual production conditions.

The brazer or brazing operator shall prepare the parts (e.g. mechanical preparation, cleaning) or accept the preparation, set up the heating means and conduct the necessary verification to carry out the test in accordance with the pBPS or BPS.

NOTE It can be of value to otherwise imitate production conditions for the qualification test as far as possible.

Test piece

The test piece may be any design of joint which is relevant to the end work. Typically, this is a basic lap or butt joint in sheet material or a sleeve joint in tube (for examples of applicable joint configurations, see Annex F).

NOTE It is possible that requirements concerning test piece design are given in the applicable product standard.

Assessment of work pieces

When assembling the test piece, the brazer or brazing operator:

— shall assess the work pieces for:

a) joint fit up;

b) joint gap;

c) degree or absence of local deformation; and

— is permitted to refuse the test piece components if the brazer or brazing operator considers that these are not in accordance with the written pBPS or BPS.

Extent of testing

Each test piece shall be tested by visual testing and one or more of the following tests:

a) ultrasonic test;

b) radiographic test;

c) peel test;

d) macroscopic examination;

e) bend test.

Visual testing

All joints shall be visually examined [see Annex A, item j)] in accordance with EN 12799 or technically equivalent standards. It can be necessary to cut open the brazed assembly to offer an internal examination. Therefore, the test may be destructive.

Non-destructive testing

Any non-destructive testing performed shall be carried out in accordance with EN 12799 or technically equivalent standards.

Destructive testing

Any destructive testing performed shall be carried out in accordance with EN 12797 or technically equivalent standards. The details of testing procedure and test specimen shall be established before any testing is undertaken.

Additional examination and testing

Additional testing may be carried out as appropriate or as agreed:

— non-destructive test methods, for example:

a) penetrant testing;

b) leak testing;

c) proof testing;

d) acoustic emission testing;

e) thermography; or

— destructive test methods, for example:

a) shear tests;

b) tensile tests;

c) metallographic examination;

d) hardness testing.

NOTE Additional testing can be required in the product standard or by contract.

Acceptance requirements for test pieces

Unless otherwise specified, the acceptance requirements for imperfections found by test methods specified in this document shall be assessed in accordance with ISO 18279:2003.

A brazer or brazing operator is qualified if the imperfections are within quality level B of ISO 18279:2003 except for excess braze metal (6BAAA) where quality level C applies and no imperfections pass through the joint length.

Re-tests

If any test fails to comply with the requirements of this document, the brazer or brazing operator shall be given the opportunity to repeat the qualification test once without further training.

If it is established that failure is due to metallurgical or other extraneous causes that cannot be directly attributed to the lack of skill of the brazer or brazing operator, an additional test is required in order to assess the quality and integrity of the new test material and/or new test conditions.

Period of validity

Initial qualification

The period of validity of the brazer or brazing operator qualification starts at the date of brazing, or the date of prolongation (see 9.2). However, the brazer qualification is not valid until all required tests are completed and accepted.

The period of validity of the brazer or brazing operator qualification is 5 years. This is providing that all the following conditions are fulfilled and documented under the control of the manufacturer.

a) The brazer or brazing operator shall be engaged with reasonable continuity in brazing work within the range of qualification. An interruption for a period of no longer than 6 months is permitted.

b) The work of the brazer or brazing operator shall be in accordance with the technical conditions under which the qualification test is carried out.

c) There shall be no specific reason to question the skill and knowledge of the brazer or brazing operator.

If any of these conditions is not fulfilled, the qualification shall be cancelled.

The qualifications of a brazer or brazer operator shall be confirmed every six months by the person responsible for brazing activities or examiner/examining body. This confirms that the brazer or brazer operator has worked within the range of qualification and extends the validity of the qualification for a further six-month period.

Prolongation

The validity of the qualification on the certificate may be prolonged for further periods of 5 years provided that each of the following conditions, in addition to those specified in 9.1, are fulfilled.

a) The production brazed joints made by the brazer or brazing operator are continuously of the required quality.

b) Records of tests, e.g. documentation of volumetric non-destructive or destructive tests, from brazing within the original range of qualification during the 6-month period immediately previous shall be filed together with the qualification certificate of the brazer. Acceptance criteria for the production test piece are in accordance with Clause 7.

The examiner or examining body shall verify compliance with conditions a) and b), and sign or issue the prolongation of the qualification test certificate for the brazer.

Certificate

A certificate shall be issued to detail that the brazer or brazing operator has passed the performance qualification test. The relevant test conditions shall be recorded on the certificate.

If the brazer or brazing operator fails any of the prescribed tests, no certificate shall be issued.

The certificate shall be issued under the sole responsibility of the examiner or examining body.

The brazer or brazing operator qualification certificate shall contain the essential variables given in Table 1. Examples of recommended formats are given in Annex B and Annex C.

The pBPS or BPS of the manufacturer shall give information about materials, brazing processes, range of qualification, etc., in accordance with this document.

Designation

The designation of a brazer or brazing operator qualification test shall comprise the following items in the order given (the system is arranged so that it can be used for computerization):

a) a reference to this document (i.e. ISO 13585:2021);

b) the essential variables in accordance with Table 1.

The type of equipment for mechanized or automatic brazing shall not be incorporated in the designation, but shall be included in the brazing operator’s qualification test certificate (see Annex C).

EXAMPLE 1 

Qualification test for flame brazing (912) of pipe (T), lap joint (LJ), copper material group 310 (Annex E), face fed CuP281 filler metal (FF), 1,5 mm material thickness (t), 20 mm outside pipe diameter (D), 5 mm overlap length (L), horizontal flow direction (H):

ISO 13585:2021 - 912 T LJ 310 CuP281 FF t1,5 D20 L5 H

EXAMPLE 2 

Qualification test for brazing operator, furnace brazing (921) with pre-placed brazing filler (PP):

ISO 13585:2021 – 921 PP

(informative) Quality requirements for brazing

The following information and requirements should be agreed and documented prior to the contract, when applicable:

a) the application standards to be used, if any, together with any supplementary requirements;

b) the BPS, including the brazing process and the brazing variables;

c) the joint design for the test pieces together with relevant tolerances and the number of test pieces required;

d) the specifications of the parent materials;

e) the specifications of the brazing consumables;

f) the handling of parent materials and brazing consumables;

g) the design and method of preparation of the test specimens and, where appropriate, the number to be taken from any test piece;

h) the acceptance criteria;

i) the principle of and procedure for retesting of a series of test pieces, including any additional requirements with regard to the number of test pieces/test specimens and any retraining and time delay conditions prior to reassessment;

j) the extent of visual testing and additional testing requirements for the non-destructive and/or destructive tests;

k) records and documentation.

(informative) Brazer qualification test certificate

Designation(s):

Manufacturer (name and address):

Photograph (if required)

pBPS/BPS – Reference No.:

Brazer's name:

Identification:

Method of identification:

Employer:

Testing standard:

Job knowledge: Acceptable/Not tested (delete as necessary)

Variables

Test piece

Range of qualification

Brazing process

 

 

Material thickness (mm)

 

 

Outside pipe diameter (mm)

 

 

Overlap length (mm)

 

 

Parent material(s)

 

 

Brazing filler type, work temperature

 

 

Brazing filler application

 

 

Product type

 

 

Filler metal flow direction

 

 

Other

 

 

Further information is stated in the attached document or in the specification for brazing procedure No.:

Type of testing

Performed and accepted

Not tested

Name of examiner or examining body:

Place, date and signature of examiner or examining body:

Date of issue:

Qualification valid until:

Visual

 

 

Radiographic

 

 

Ultrasonic

 

 

Peel

 

 

Other

 

 

 

 

 

 

 

Confirmation of qualification by employer or other responsible person (every six months), required for the validity of the certificate.

Prolongation of qualification by examiner or examining body (every five years).

Date

Signature

Position or title

Date

Signature

Position or title

 

 

 

 

 

 

(informative) Brazing operator qualification test certificate

Designation(s):

Manufacturer (name and address):

Photograph (if required)

Certificate reference No.:

pBPS/BPS – Reference No.:

Brazer's name:

Identification:

Method of identification:

Employer:

Testing standard:

Job knowledge: Acceptable/Not tested (delete as necessary)

Variables

Test piece

Range of qualification

Brazing process

 

 

Type pf brazing equipment

 

 

Further information is stated in the attached document or in the specification for brazing procedure No.:

Type of testing

Performed and accepted

Not tested

Name of examiner or examining body:

Place, date and signature of examiner or examining body:

Date of issue:

Qualification valid until:

Visual

 

 

Radiographic

 

 

Ultrasonic

 

 

Peel

 

 

Other

 

 

 

 

 

 

 

Confirmation of qualification by employer or other responsible person (every six months), required for the validity of the certificate.

Prolongation of qualification by examiner or examining body (every three years).

Date

Signature

Position or title

Date

Signature

Position or title

 

 

 

 

 

 

(informative) Other non-essential variables

Fuel/gases

Fuel/gases shall be selected to be relevant to the heating requirement. Typical examples include:

a) natural gas/air;

b) natural gas/oxygen;

c) propane/air;

d) propane/oxygen;

e) acetylene/air;

f) acetylene/oxygen.

Brazing torch

A torch similar to that used in production shall be used.

Joint location

On-site brazing can require a brazer to make joints in close proximity to walls, etc. Joints may be horizontal or vertical. Similar constraints on access for torches can also be encountered in mass production. Qualification tests shall be designed to reproduce these conditions.

Jigs and fixtures

If necessary, jigs and fixtures shall be used to position the components of a test piece.

Test location

The qualification test shall take place in a workshop but simulate the on-site limitations. It enables the ability of the brazer to perform on-site and workshop brazing operations in the selected jointing technique to be judged.

(normative) Material grouping system

Material grouping numbers

Parent metals have been grouped by metal number (M No.) so that the required number of qualifications can be reduced. Substitution of one parent material for another, for any purpose other than for qualification, even when within the allowable rules, should be made only after an evaluation of all the factors involved, for example:

— consideration of the compatibility from the standpoint of metallurgical properties;

— post-weld heat treatment;

— design;

— mechanical properties;

— service requirements.

Basis for classification of parent materials for brazing qualification

General

The required tensile strength when performing tension tests shall be the annealed strength of the parent material. Where the tensile strength is given in a specification, the strength shall be that of the thickest parent material up to 25 mm.

Where classification is dependent on the amount of a given element, the controlling value is the maximum content given in the parent material specification.

The parent metal (M) numbers for ferrous alloys are listed below.

Ferrous alloys

100

Steels containing ≤1 % (by mass) chromium

110

Steels containing >1 % (by mass) chromium

 

NOTE Steels with ≥12 % (by mass) chromium are included in stainless steels.

120

Steels containing aluminium or titanium

130

Stainless steels, austenitic

140

Stainless steels, austenitic containing titanium <0,3 % (by mass)

150

Stainless steels, martensitic, and ferritic

160

Stainless steels, martensitic, and ferritic containing <0,3 % (by mass) combined aluminium and titanium

170

Cast iron

180

Cast iron, austenitic

Aluminium and aluminium alloys

200

Aluminium and aluminium alloys containing no magnesium

210

Aluminium alloys containing <1 % (by mass) magnesium

220

Aluminium alloys containing ≥1 % (by mass) magnesium

Copper and copper alloys

300

Copper and copper alloys

310

Copper alloys containing 0,5 % to 1 % (by mass) lead

320

Copper alloys containing >1 % (by mass) and ≤7 % (by mass) lead

330

Copper alloys containing >1 % (by mass) silicon

340

Copper alloys containing 0,5 % to 1 % (by mass) aluminium or beryllium

350

Copper alloys containing >1 % and ≤5 % (by mass) aluminium or beryllium

360

Copper alloys containing ≤5 % (by mass) aluminium or beryllium

Nickel and nickel alloys

400

Nickel and nickel-copper alloys

410

Nickel-molybdenum alloys

420

Nickel-chromium-iron and nickel-chromium-molybdenum alloys

430

Nickel-chromium-iron and nickel-chromium-molybdenum alloys containing <1,5 % (by mass) combined aluminium and titanium

Titanium and titanium alloys

500

Zirconium and zirconium alloys

600

Magnesium alloys

700

Cobalt alloys

800

(informative) Examples of test pieces

Examples of test pieces are shown in Figures F.1 to F.5.

Key

b

width

l

total length

t

thickness

lo

overlap length

Figure 0\IF >= 1 "C." F.1 — Test piece — Lap joint

Key

b

width

l

total length

t

thickness

Figure 0\IF >= 1 "C." F.2 — Test piece — Butt joint

Key

lo

overlap

Figure F.0\IF >= 1 "C." 3 — Test piece — Simple lap joint (socket joint)

Figure F.0\IF >= 1 "C." 4 — Test piece — Multiple lap joints (socket joints)

Key

t1

thickness of first component

t2

thickness of second component

Figure F.0\IF >= 1 "C." 5 — Test piece — T-joint

Bibliography

[1] ISO 11745, Brazing for aerospace applications — Qualification test for brazers and brazing operators — Brazing of metallic components

[2] ISO 18496, Brazing — Fluxes for brazing — Classification and technical delivery conditions