EN 12168:2024

SLOVENSKI STANDARD
01-december-2024
Baker in bakrove zlitine - Votle palice za prosto strojno obdelavo
Copper and copper alloys - Hollow rod for free machining purposes
Kupfer und Kupferlegierungen - Hohlstangen für die spanende Bearbeitung
Cuivre et alliages de cuivre - Barres creuses pour décolletage
Ta slovenski standard je istoveten z: EN 12168:2024
ICS:
77.150.30 Bakreni izdelki Copper products
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN 12168
EUROPEAN STANDARD
NORME EUROPÉENNE
October 2024
EUROPÄISCHE NORM
ICS 77.150.30 Supersedes EN 12168:2016
English Version
Copper and copper alloys - Hollow rod for free machining
purposes
Cuivre et alliages de cuivre - Barres creuses pour Kupfer und Kupferlegierungen - Hohlstangen für die
décolletage spanende Bearbeitung
This European Standard was approved by CEN on 30 June 2024.

CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this
European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references
concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN
member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by
translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management
Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and
United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2024 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 12168:2024 E
worldwide for CEN national Members.

Contents Page
European foreword . 4
Introduction . 6
1 Scope . 7
2 Normative references . 7
3 Terms and definitions . 7
4 Designations. 9
4.1 Material . 9
4.1.1 General . 9
4.1.2 Symbol . 9
4.1.3 Number . 9
4.2 Material condition . 9
4.3 Product . 9
5 Ordering information . 12
6 Requirements . 14
6.1 Composition . 14
6.2 Mechanical properties . 14
6.3 Resistance to dezincification . 14
6.4 Residual stress level . 14
6.5 Dimensions and tolerances . 14
6.5.1 Diameter or width across-flats . 14
6.5.2 Tolerance on wall thickness . 14
6.5.3 Eccentricity . 15
6.5.4 Shape tolerances . 15
6.5.5 Straightness . 15
6.5.6 Length . 15
6.5.7 Corner radii . 15
6.5.8 Twist of polygonal hollow rod . 16
6.6 Surface quality. 16
6.7 Internal inclusion . 17
7 Sampling . 17
7.1 General . 17
7.2 Analysis . 17
7.3 Mechanical tests . 17
7.4 Dezincification resistance and stress corrosion resistance tests . 17
8 Test methods . 18
8.1 Analysis . 18
8.2 Tensile test . 18
8.2.1 General . 18
8.2.2 Location of test pieces . 18
8.2.3 Shape and size of test pieces . 18
8.2.4 Procedure for testing . 18
8.2.5 Determination of results . 18
8.3 Hardness test . 18
8.4 Dezincification resistance test . 19
8.5 Stress corrosion resistance test . 19
8.6 Retests . 19
8.6.1 Analysis, tensile, hardness and dezincification resistance tests . 19
8.6.2 Stress corrosion resistance test . 19
8.7 Rounding of results . 19
9 Certificate of Compliance and inspection documentation . 20
9.1 Certificate of Compliance . 20
9.2 Inspection documentation . 20
10 Marking, packaging, labelling . 20
Annex ZA (informative) Relationship between this European Standard and the essential
requirements of Directive 2014/68/EU (Pressure equipment Directive) aimed to be
covered . 39
Bibliography . 40

European foreword
This document (EN 12168:2024) has been prepared by Technical Committee CEN/TC 133 “Copper and
copper alloys”, the secretariat of which is held by DIN.
This European Standard shall be given the status of a national standard, either by publication of an
identical text or by endorsement, at the latest by April 2025, and conflicting national standards shall be
withdrawn at the latest by April 2025.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
This document supersedes EN 12168:2016.
In comparison with EN 12168:2016, the following significant technical changes were made:
a) Modification of the note in Clause 1;
b) Introduction of eddy current test parameters in 6.6;
c) Introduction of 6.7 Internal inclusion;
d) Modification of the definition of diameter or width across-flats in 6.5.4.1;
e) Addition of a new Figure for straightness at 6.5.5 and modification of values in Table 13;
f) Introduction in the chemical composition Tables of a footnote to explain the meaning of elements for
which no upper and lower limits are specified;
g) Deletion of alloys groups in Table 3;
h) Modification of the chemical composition of CuZn39Pb3 (CW614N), CuZn40Pb2 (CW617N),
CuZn35Pb1,5AlAs (CW625N) and CuZn33Pb1,5AlAs (CW626N) in Table 3;
i) Addition of a new alloy CuZn40Pb1 (CW627N) in Table 3 and Table 7;
j) Modification of the chemical composition of CuZn33Pb1AlSiAs (CW725R) in Table 4;
k) Addition of a new alloy CuZn36Si1P (CW726R) in Table 4 and Table 8;
l) Modification of the range of dimensions in Table 9 and in Table 11;
m) Addition of Table 18 and Table 19;
n) Addition of Annex ZA.
This document is one of a series of European Standards for the copper and copper alloy products rod,
wire, profile and forgings. Other products are specified as follows:
— EN 12163, Copper and copper alloys — Rod for general purposes;
— EN 12164, Copper and copper alloys — Rod for free machining purposes;
— EN 12165, Copper and copper alloys — Wrought and unwrought forging stock;
— EN 12166, Copper and copper alloys — Wire for general purposes;
— EN 12167, Copper and copper alloys — Profiles and bars for general purposes;
— EN 13601, Copper and copper alloys — Copper rod, bar and wire for general electrical purposes;
— EN 13602, Copper and copper alloys — Drawn, round copper wire for the manufacture of electrical
conductors;
— EN 13605, Copper and copper alloys — Copper profiles and profiled wire for electrical purposes.
This document has been prepared under a standardization request addressed to CEN by the European
Commission. The Standing Committee of the EFTA States subsequently approves these requests for its
Member States.
For the relationship with EU Legislation, see informative Annex ZA, which is an integral part of this
document.
Any feedback and questions on this document should be directed to the users’ national standards body.
A complete listing of these bodies can be found on the CEN website.
According to the CEN-CENELEC Internal Regulations, the national standards organisations of the
following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia,
Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland,
Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Republic of North
Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and the United
Kingdom.
Introduction
The European Committee for Standardization (CEN) draws attention to the fact that it is claimed that
compliance with this document may involve the use of a patent concerning the alloy
CuZn36Si1P (CW726R) given in 6.1.
CEN takes no position concerning the evidence, validity and scope of this patent right.
The holder of this patent right has ensured the CEN that he is willing to negotiate licenses under
reasonable and non-discriminatory terms and conditions with applicants throughout the world. In this
respect, the statement of the holder of this patent right is registered with CEN.
— For CuZn36Si1P (CW726R) information may be obtained from:
Luvata Oy
Kuparitie 5
28330 Pori
FINLAND
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights other than those identified above. CEN shall not be held responsible for identifying any or
all such patent rights.
CEN and CENELEC maintain online lists of patents relevant to their standards. Users are encouraged to
consult the lists for the most up to date information concerning patents
(https://www.cencenelec.eu/european-standardization/ipr-and-patents/patents/).
Due to developing legislation, the composition of a material may be restricted to the composition
specified in this European Standard with respect to individual uses (e.g. for the use in contact with
drinking water in some Member States of the European Union). These individual restrictions are not part
of this European Standard. Nevertheless, for materials for which traditional and major uses are affected,
these restrictions are indicated. The absence of an indication, however, does not imply that the material
can be used in any application without any legal restriction.
1 Scope
This document specifies the composition, property requirements and dimensional tolerances for copper
alloy hollow rod, finally produced by drawing or extruding, specifically intended for free machining
purposes.
NOTE Hollow products having an outside diameter greater than 80 mm and/or a wall thickness less than 2 mm
are most frequently specified in EN 12449.
The sampling procedures, the methods of test for verification of conformity to the requirements of this
document, are also specified.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
EN 764-5:2014, Pressure equipment — Part 5: Inspection documentation of metallic materials and
compliance with the material specification
EN 10204:2004, Metallic products — Types of inspection documents
EN 14977:2006, Copper and copper alloys — Detection of tensile stress — 5 % ammonia test
EN 17263:2019, Copper and copper alloys — Eddy current testing on the outer surface of rods, bars, hollow
rods and wires for the detection of defects by encircling test coil
EN ISO 6506-1:2014, Metallic materials — Brinell hardness test — Part 1: Test method (ISO 6506-1:2014)
EN ISO 6507-1:2018, Metallic materials — Vickers hardness test — Part 1: Test method (ISO 6507-1:2018)
EN ISO 6509-1:2014, Corrosion of metals and alloys — Determination of dezincification resistance of
copper alloys with zinc — Part 1: Test method (ISO 6509-1:2014)
EN ISO 6892-1:2019, Metallic materials — Tensile testing — Part 1: Method of test at room temperature
(ISO 6892-1:2019)
ISO 6957:1988, Copper alloys — Ammonia test for stress corrosion resistance
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— IEC Electropedia: available at https://www.electropedia.org/
— ISO Online browsing platform: available at https://www.iso.org/obp
3.1
hollow rod
straight product, of uniform cross-section along its whole length with an enclosed void for which the
longitudinal axes of its external contour and its internal contour, which is the boundary with the enclosed
void, are coincidental
Note 1 to entry: The external and internal contours of the rod, at any cross-section, can be that of a circle, square,
rectangle, hexagon, or octagon, or with slight modification of those basic shapes by inclusion of detail(s) of relatively
small size to the remainder of the cross-section. Examples of hollow rod cross-sections are shown in Figure 1.

Figure 1 — Examples of hollow rod cross-sections
3.2
deviation from circular form
difference between the maximum and the minimum outside diameters measured at any one cross-section
of the product
3.3
eccentricity
difference between the maximum and the minimum wall thickness, measured in the same cross-section
perpendicular to the axis of the hollow rod, expressed as a percentage of the sum of the maximum and
minimum wall thicknesses (s and s ):
max. min.
ss−
max. min.
e × 100
s + s
max. min.
Note 1 to entry: For polygons, wall thickness is measured perpendicular to the mid-points of the flat outside
surfaces.
=
4 Designations
4.1 Material
4.1.1 General
The material is designated either by symbol or by number (see Tables 1 to 4).
4.1.2 Symbol
The material symbol designation is based on the designation system given in ISO 1190-1:1982.
NOTE Although material symbol designations used in this standard might be the same as those in other
standards using the designation system given in ISO 1190-1:1982, the detailed composition requirements are not
necessarily the same.
4.1.3 Number
The material number designation is in accordance with the system given in EN 1412:2016.
4.2 Material condition
For the purposes of this document, the following designations, which are in accordance with the system
given in EN 1173:2008, apply for the material condition:
M material condition for the product as manufactured without specified mechanical
properties;
R. material condition designated by the minimum value of tensile strength requirement for
the product with mandatory tensile property requirements;
H. material condition designated by the minimum value of hardness requirement for the
product with mandatory hardness requirements;
S (suffix) material condition for a product which is stress relieved.
Products in the M or H. material condition may be specially processed (i.e. mechanically or thermally
stress relieved) in order to lower the residual stress level to improve the resistance to stress corrosion
and the dimensional stability on machining [see Clause 5 list entry l), list entry m) and 8.5].
Exact conversion between material conditions designated R. and H. is not possible.
Except when the suffix S is used, material condition is designated by only one of the above designations.
4.3 Product
The product designation provides a standardized pattern of designation from which a rapid and
unequivocal description of a product can be conveyed in communication. It provides mutual
comprehension at the international level with regard to products which meet the requirements of the
relevant document.
The product designation is no substitute for the full content of the document.
The product designation for products to this document shall consist of:
a) denomination (hollow rod);
b) number of this European Standard (EN 12168);
c) material designation, either symbol or number (see Tables 1 to 4);
d) DW for compliance in the chemical composition according to the 4 MS Common Composition List.
This information is mandatory in the case in which the product is used for drinking water
applications according to the 4 MS Common Composition List and not to be given in other cases (see
Bibliography [11]);
e) material condition designation (see Tables 5 to 8);
f) external and/or internal cross-sectional shape (the following designations shall be used as
appropriate: RND for round, SQR for square, RCT for rectangular, HEX for hexagonal, OCT for
octagonal, PFL for profile);
g) nominal cross-sectional dimensions (see Clause 5, list entry g)) or, for profiles, the number of the
profile or a fully dimensioned and toleranced drawing, and:
1) tolerance class A, B or C added to the external dimension (see Table 9); and/or
2) tolerance class A or B added to the bore diameter (see Table 11);
h) wall thickness (the following designation shall be used for wall thickness: WT) (see Table 10);
i) for square, hexagonal or octagonal external shape, the corner shape (the following designations shall
be used as appropriate: SH for sharp, RD for rounded) (see Table 15).
A typical product designation is shown in the following examples.
EXAMPLE 1 Hollow rod for free machining purposes conforming to this document, in material designated either
CuZn40Pb2 or CW617N, for standard applications, in material condition H090, round external shape and bore,
nominal outside diameter 40 mm, tolerance Class B, and nominal wall thickness 10 mm will be designated as
follows:
EXAMPLE 2 Hollow rod for free machining purposes conforming to this document, in material designated either
CuZn40Pb2 or CW617N, for drinking water applications according to the 4 MS Common Composition List, in
material condition H090, round external shape and bore, nominal outside diameter 40 mm, tolerance Class B, and
nominal wall thickness 10 mm will be designated as follows:
EXAMPLE 3 Hollow rod for free machining purposes conforming to this document, in material designated either
CuZn40Pb2 or CW617N, for standard applications, in material condition H090, hexagonal external shape, 60 mm
nominal width across-flats dimension, tolerance Class A, round bore of nominal diameter 20 mm, tolerance Class B
sharp corners, will be designated as follows:

EXAMPLE 4 Hollow rod for free machining purposes conforming to this document, in material designated either
CuZn40Pb2 or CW617N, for drinking water applications according to the 4 MS Common Composition List, in
material condition H090, hexagonal external shape, 60 mm nominal width across-flats dimension, tolerance Class A,
round bore of nominal diameter 20 mm, tolerance Class B sharp corners, will be designated as follows:
5 Ordering information
In order to facilitate the enquiry, order and confirmation of order procedures the following information
shall be specified:
a) mass of product required;
b) denomination (hollow rod);
c) number of this European Standard (EN 12168);
d) material designation (see Tables 1 to 4);
e) material condition designation (see 4.2 and Tables 5 to 8) if it is other than M;
f) DW for compliance in the chemical composition according to the 4 MS Common Composition List.
This information is mandatory in the case in which the product is used for drinking water
applications according to the 4 MS Common Composition List and not to be given in other cases;
g) nominal cross-sectional dimensions or, in the case of hollow profiles, by a fully dimensioned and
toleranced drawing:
To define the nominal cross-sectional dimensions of a hollow rod, it should state one of the following:
1) the external dimensions and the wall thickness (tolerances given in Tables 9 and 10); or
2) the internal dimensions and the wall thickness (tolerances given in Tables 11 and 10); or
3) the external and internal dimensions (tolerances given in Tables 9 and 11) and the maximum
eccentricity (tolerances given in Table 12); or
h) whether:
1) class A, B or C tolerances shall apply to external dimensions (see Table 9); and/or
2) class A or B tolerances shall apply to internal dimensions (see Table 11); unless the choice of
these tolerance classes is left to the discretion of the supplier;
i) for hollow rod having a square, hexagonal or octagonal external shape, whether “sharp” or “rounded”
corners are required unless the corner radii of the rod are left to the discretion of the supplier
(see 6.5.7 and Table 13);
j) length of product required. Normally hollow rod is supplied to “nominal length” tolerances (see 6.5.6
and Table 14);
It is recommended that the product designation, as described in 4.3, is used for items b) to j).
In addition, it shall also state on the enquiry and order any of the following, if required:
k) whether the products according to 6.3, are required to pass a dezincification resistance test (see 8.4);
l) whether the products are required to pass a stress corrosion resistance test. If so which test method
shall be used (see 8.5), if the choice is not left to the discretion of the supplier.
m) whether the products shall be supplied in a thermally stress relieved material condition;
n) whether special surface quality is required (see 6.6);
o) whether surface quality test is required (see 6.6) and the class;
p) whether a Certificate of Compliance is required (see 9.1);
q) whether an inspection document is required, and if so, which type (see 9.2);
r) whether there are any special requirements for marking, packaging or labelling (see Clause 10).
EXAMPLE Ordering details for 1 000 kg of hollow rod for free machining purposes conforming to EN 12168,
in material designated either CuZn40Pb2 or CW617N, for drinking water application according to the 4 MS Common
Composition List, in material condition H090, round external shape, nominal outside diameter 40 mm, tolerance
class B, and nominal wall thickness 10 mm, tolerance class A, nominal length 3 000 mm:
1 000 kg Hollow rod — CuZn40Pb2 — DW — H090 — RND40B × WT10A
EN 12168
— nominal length 3 000 mm
or
1 000 kg Hollow rod — CW617N — DW — H090 — RND40B × WT10A
EN 12168
— nominal length 3 000 mm
6 Requirements
6.1 Composition
The composition shall conform to the requirements for the appropriate material given in Tables 1 to 4.
Due to developing legislation, specific applications (see 4.3) may require restrictions in the chemical
composition. In this case the limitations shall be specified in the ordering information (see Clause 5 f)).
6.2 Mechanical properties
The properties shall conform to the appropriate requirements given in Tables 5 to 8. The tests shall be
carried out in accordance with 8.2 or 8.3.
6.3 Resistance to dezincification
This requirement only applies to materials that are declared resistant to dezincification.
The maximum depth of dezincification, in any direction, of CuZn38As (CW511L), CuZn36Pb2As
(CW602N), CuZn32Pb2AsFeSi (CW709R), CuZn21Si3P (CW724R) and CuZn33Pb1AlSiAs (CW725R)
products shall not exceed 100 µm. For the alloys CuZn35Pb1,5AlAs (CW625N), CuZn33Pb1,5AlAs
(CW626N) the maximum depth of dezincification, in any direction, shall not exceed 200 µm.
The test shall be carried out in accordance with 8.4.
NOTE Shape and distribution of beta phase aggregates can influence the dezincification resistance of products.
Special requirements relating to shape and distribution of ß phase aggregates are subject to agreement between the
involved parties
Products in alloys other than CuZn21Si3P (CW724R) shall be subjected to heat treatment approximately
in the range 500 °C to 550 °C.
Should the user need to heat the material out of the range before specified (i.e. soldering, brazing or
welding operations) then advice should be sought from the supplier.
6.4 Residual stress level
Products ordered and supplied in the stress relieved condition (see 4.2, 2nd paragraph) shall show no
evidence of cracking if tested. The tests shall be carried out in accordance with 8.5.
6.5 Dimensions and tolerances
6.5.1 Diameter or width across-flats
When specified at the time of the order (see Clause 5 list entry g)), external diameter or width across-
flats at any point shall conform to the tolerances given in Table 9.
When specified at the time of the order (see Clause 5 list entry g)), internal diameter of the bore at any
point shall conform to the tolerances given in Table 11.
For internal shape other than circle the tolerances are subject to agreement between the involved parties.
6.5.2 Tolerance on wall thickness
When specified at the time of the order (see Clause 5 list entry g)), the wall thickness shall conform to the
tolerances given in Table 10. For hollow rod having a polygonal external shape, the wall thickness shall
be measured at the centre of each flat.
6.5.3 Eccentricity
When specified at the time of the order (see Clause 5 list entry g)), the percentage eccentricity of hollow
rod having a circular or polygonal external cross-section shall conform to Table 12.
6.5.4 Shape tolerances
6.5.4.1 Circular cross-sections
For hollow rod having a circular external cross-section and for circular bores, the deviation from
circularity of their diameters (see 3.2) shall not exceed half the appropriate range of the tolerance on
diameter given in Tables 9 and 11 respectively.
6.5.4.2 Polygonal external cross-sections
For hollow rod having a polygonal external cross-section, the width across-flats at any one cross-section,
measured at the centre of each pair of opposite faces, shall not differ by more than half the range of the
tolerance given in Table 9.
6.5.5 Straightness
For hollow rod of length 1 000 mm or over, the deviation from straightness, defined as the curvature
(depth of arc) against a datum line when the product is lying flat in a horizontal plane (see Figure 2), shall
conform to the tolerances given in Table 13.
NOTE Outside this range, the deviation from straightness is subject to agreement between the involved parties.
Dimensions in millimetres
Key
h depth of arc in any length l of 1000
1 1
h depth of arc in any length l of 400
2 2
Figure 2 — Measurement of straightness
6.5.6 Length
Hollow rod shall be supplied as “nominal lengths”, generally in the preferred lengths given in Table 14,
and shall conform to the tolerances in the table.
Subject to agreement between the involved parties, an agreed proportion of underlength hollow rod may
be included in a consignment of “nominal lengths” hollow rod.
6.5.7 Corner radii
The corner radii of hollow rod having a square, hexagonal or octagonal external shape, shall conform to
Table 15 [see Clause 5 list entry i)].
Except in cases of dispute, the corners should be measured directly, either by use of a gauge or an optical
projector. In cases of dispute, the method by optical projector should be used.
6.5.8 Twist of polygonal hollow rod
The maximum permitted twist V (see Figure 3) of hollow rod having a square, hexagonal or octagonal
external shape, as measured between two cross-sections along the rod, shall conform to Table 16.

Key
1 reference plane
V twist
W width across-flats
Figure 3 — Measurement of twist of polygonal hollow rod
6.6 Surface quality
The surfaces shall be clean and smooth. The hollow rods may have a superficial film of drawing lubricant
or, if annealed or thermally stress relieved, a superficial, dull, iridescent oxide film, securely adherent on
the surfaces.
Discontinuous irregularities on the surfaces of the hollow rods are permitted if they are within the
dimensional tolerances.
Since surface discontinuities (cracks, overlapping, scale, isolated pores, pits, grooves, etc.) cannot be
completely avoided during manufacturing (hot and cold formation, heat treatments, handling and
storage) and since they are retained when drawing, agreements shall be made regarding surface quality.
If eddy current test is requested, the test method given in EN 17263:2019 shall be applied using reference
standard according to Table 18 for hollow round rod. For polygonal hollow rod the reference standard
shall be agreed between the involved parties.
The sensitivity is to be set in such a way that the smallest signal of the borehole(s) just exceeds the
response threshold (acceptance level).
The surface quality of the products shall be one of the classes according to Table 19 where:
K = ratio of the signal for the lower detection threshold to the signal for the normal detection
threshold (normal acceptance level)
d = a maximum density of defects referred to a pre-set length of 300 mm (L )
0 0
% of sensitivity = percentage of acceptance level
If single hollow rods are tested unexamined ends exist.
Other surface control methods can be used by agreement between the involved parties.
Special requirements (e.g. pickling, degreasing, etc.) relating to the surface quality shall be agreed
between the involved parties [see Clause 5, list entry n)].
6.7 Internal inclusion
Freedom of internal inclusions cannot be ensured in any copper alloys.
7 Sampling
7.1 General
When required or for use in cases of dispute, an inspection lot shall be sampled in accordance with 7.2 to
7.4.
7.2 Analysis
The sampling rate shall be in accordance with Table 17. A test sample, depending on the analytical
technique to be employed, shall be prepared from each sampling unit and used for the determination of
the composition.
When preparing the test sample, care should be taken to avoid contaminating or overheating the test
sample. Carbide tipped tools are recommended; steel tools, if used, should be made of magnetic material
to assist in the subsequent removal of extraneous iron. If the test samples are in finely divided form (e.g.
drillings, millings), they should be treated carefully with a strong magnet to remove any particles of iron
introduced during preparation.
In cases of dispute concerning the results of analysis, the full procedure given in ISO 1811-2 should be
followed.
Results may be used from analyses carried out at an earlier stage of manufacturing the product, e.g. at the
casting stage, if the material identity is maintained and if the manufacturer can ensure the traceability of
the product.
7.3 Mechanical tests
The sampling rate shall be in accordance with Table 17. Sampling units shall be selected from the finished
products. The test samples shall be cut from the sampling units. Test samples, and test pieces prepared
from them, shall not be subjected to any further treatment, other than any machining operations
necessary in the preparation of the test pieces.
7.4 Dezincification resistance and stress corrosion resistance tests
The sampling rate which shall be applied to finished products shall be:
— for products that have been heat treated: one sampling unit per heat treatment batch;
— for products that have not been heat treated: in accordance with Table 17.
The test samples shall be cut from the sampling units. Test samples and test pieces prepared from them
shall not be subjected to any further treatment, other than any machining operations necessary in the
preparation of the test pieces.
8 Test methods
8.1 Analysis
Analysis shall be carried out on the test pieces, or test portions, prepared from the test samples obtained
in accordance with 7.2. Except in cases of dispute, the analytical methods used shall be at the discretion
of the supplier. In case of dispute the methods of analysis to be used shall be agreed between the disputing
parties. For expression of results, the rounding rules given in 8.7 shall be used.
8.2 Tensile test
8.2.1 General
Tensile test pieces shall be prepared in accordance with 8.2.2 and 8.2.3 and the test shall be carried out
in accordance with 8.2.4.
8.2.2 Location of test pieces
Test pieces shall be machined from one of the following locations in the test sample obtained in
accordance with 7.3:
a) for test samples from products up to and including 25 mm diameter, or width across-flats or
equivalent cross-sectional area, the test piece shall be coaxial with the product;
b) for test samples from products over 25 mm diameter, or width across-flats or equivalent cross-
sectional area, the test piece shall be tested in full section or extracted from the wall of the hollow
rod with the longitudinal axis parallel to that of the product. For thickness lower than 11 mm the test
piece shall be a circumferential portion of the wall of the original hollow rod (longitudinal strip). For
thickness greater than 11 mm a cylindrical test piece shall be obtained by machining the wall of the
original hollow rod; the longitudinal axis of the test piece shall be mid-way between the internal and
external surface.
8.2.3 Shape and size of test pieces
Test pieces shall be in accordance with EN ISO 6892-1:2019.
Elongation requirements for hollow rod of thickness are based on original gauge lengths of 5,65 S mm
o
(A), where S is the original cross-sectional area of the test piece in square millimetres.
o
8.2.4 Procedure for testing
The tensile test shall be carried out in accordance with the method given in EN ISO 6892-1:2019.
8.2.5 Determination of results
The tensile strength and the elongation shall be determined from the tensile test results obtained in
accordance with 8.2.4. For expression of results the rounding rules given in 8.7 shall be used.
8.3 Hardness test
Hardness shall be determined on test pieces cut from the test sample obtained in accordance with 7.3.
The test shall be carried out in accordance with EN ISO 6506-1:2014 or EN ISO 6507-1:2018 and the
impression/ indentation made on the cross-section of the product mid-way between the external and
internal surfaces.
8.4 Dezincification resistance test
The test method given in EN ISO 6509-1:2014 shall be used on the test samples obtained in accordance
with 7.4 [see Clause 5 list entry k)]. A test piece shall be taken from each test sample, so as to expose a
prepared cross-sectional surface to the test solution.
At the completion of the test the maximum depth of dezincification in a longitudinal direction shall be
measured.
8.5 Stress corrosion resistance test
The test method given in either ISO 6957:1988 (using pH 10,0) or EN 14977:2006 shall be used on the
test pieces prepared from the test samples obtained in accordance with 7.4. The choice of which of these
tests is used shall be at the discretion of the supplier, unless a preference is agreed at the time of the order
[see Clause 5 list entry k)].
8.6 Retests
8.6.1 Analysis, tensile, hardness and dezincification resistance tests
If there is a failure of one, or more than one, of the tests in 8.1, 8.2, 8.3 or 8.4, two test samples from the
same inspection lot shall be permitted to be selected for retesting the failed property (properties). One
of these test samples shall be taken from the same sampling unit as that from which the original failed
test piece was taken, unless that sampling unit is no longer available, or has been withdrawn by the
supplier.
If the test pieces from both test samples pass the appropriate test(s), then the inspection lot represented
shall be deemed to conform to the particular requirement(s) of this standard. If a test piece fails a test,
the inspection lot represented shall be deemed not to conform to this document.
NOTE If an inspection lot of dezincification resistant alloys fails the dezincification resistance test when tested
or retested, the supplier has the option to heat treat, or to further heat treat, the inspection lot and resubmit it for
all the tests called for on the order, except for analysis.
8.6.2 Stress corrosion resistance test
If a test piece fails the test, the inspection lot represented by the failed test piece shall be permitted to be
subjected to a stress relieving treatment. A further test sample shall then be selected in accordance with
7.4.
If a test piece from the further test sample passes the test, the stress relieved products shall be deemed
to conform to the requirements of this standard for residual stress level and shall
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