SIST EN 10270-2:2012

SLOVENSKI STANDARD
oSIST prEN 10270-2:2008
01-september-2008
-HNOHQDåLFD]DY]PHWLGHO9ROMXNDOMHQDLQSRSXãþHQDMHNOHQDåLFD]DY]PHWL
Steel wire for mechanical springs - Part 2: Oil hardened and tempered spring steel wire
Stahldraht für Federn - Teil 2: Ölschlussvergüteter Federstahldraht
Fils en acier pour ressorts mécaniques - Partie 2: Fils en acier trempés à l'huile et
revenus
Ta slovenski standard je istoveten z: prEN 10270-2
ICS:
77.140.25 Vzmetna jekla Spring steels
77.140.65 Jeklene žice, jeklene vrvi in Steel wire, wire ropes and
verige link chains
oSIST prEN 10270-2:2008 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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oSIST prEN 10270-2:2008

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oSIST prEN 10270-2:2008
EUROPEAN STANDARD
DRAFT
prEN 10270-2
NORME EUROPÉENNE
EUROPÄISCHE NORM
June 2008
ICS 77.140.25 Will supersede EN 10270-2:2001
English Version
Steel wire for mechanical springs - Part 2: Oil hardened and
tempered spring steel wire
Fils en acier pour ressorts mécaniques - Partie 2: Fils en Stahldraht für Federn - Teil 2: Ölschlussvergüteter
acier trempés à l'huile et revenus Federstahldraht
This draft European Standard is submitted to CEN members for enquiry. It has been drawn up by the Technical Committee ECISS/TC 30.
If this draft becomes a European Standard, 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.
This draft European Standard was established by CEN 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 Management Centre has the
same status as the official versions.
CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland,
France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal,
Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.
Recipients of this draft are invited to submit, with their comments, notification of any relevant patent rights of which they are aware and to
provide supporting documentation.
Warning : This document is not a European Standard. It is distributed for review and comments. It is subject to change without notice and
shall not be referred to as a European Standard.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: rue de Stassart, 36  B-1050 Brussels
© 2008 CEN All rights of exploitation in any form and by any means reserved Ref. No. prEN 10270-2:2008: E
worldwide for CEN national Members.

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oSIST prEN 10270-2:2008
prEN 10270-2:2008 (E)
Contents Page
Foreword.3
1 Scope.4
2 Normative references.4
3 Terms and definitions .4
4 Classification and designation.5
4.1 Classification.5
4.2 Designation.5
5 Information to be supplied by the purchaser .6
6 Requirements.6
6.1 Form of delivery.6
6.2 Surface finish.6
6.3 Chemical composition.6
6.4 Non metallic inclusions.7
6.5 Mechanical properties.7
6.6 Technological properties.12
6.7 Surface quality.12
6.8 Dimensions and dimensional tolerances.13
7 Testing and inspection.14
7.1 Inspection and inspection documents .14
7.2 Extent of testing for specific inspection .14
7.3 Sampling.14
7.4 Test methods.15
7.5 Retests.16
8 Marking and packaging.16
Annex A (informative) Additional information.18
A.1 Modulus of elasticity and shear modulus at room temperature.18

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oSIST prEN 10270-2:2008
prEN 10270-2:2008 (E)
Foreword
This document (prEN 10270-2:2008) has been prepared by Technical Committee ECISS/TC 30 “Steel wires”,
the secretariat of which is held by AFNOR.
This document is currently submitted to the CEN Enquiry.
This document will supersede EN 10270-2:2001.
This European Standard for steel wire for mechanical springs is composed of the following parts:
 Part 1: Patented cold drawn unalloyed spring steel wire
 Part 2: Oil hardened and tempered spring steel wire
 Part 3: Stainless spring steel wire
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oSIST prEN 10270-2:2008
prEN 10270-2:2008 (E)
1 Scope
1.1 This Part of EN 10270 applies to oil hardened and tempered spring steel wire made from unalloyed or
alloyed steels. They are primarily subject to torsional stresses such as in compression and extension springs
and in special cases also for applications where the spring wire is subject to bending stresses such as lever
springs.
As a rule unalloyed steels are used for applications at room temperature whereas alloyed steels are generally
used at a temperature above room temperature. Alloyed steels may also be chosen for above average tensile
strengths.
1.2 In addition to this part of EN 10270 the general technical delivery requirements of EN 10021 are
applicable.
2 Normative references
The following referenced documents are indispensable for the application 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 10002-1, Metallic materials — Tensile test — Part 1: Method of test at ambient temperature.
EN 10021, General technical delivery requirements for steel products.
EN 10204, Metallic products — Types of inspection documents.
EN 10218-1, Steel wire and wire products — General — Part 1: Test methods.
EN 10218-2, Steel wire and wire products — General — Part 2: Wire dimensions and tolerances.
ENV 10247, Micrographic examination of the non-metallic inclusion content of steels using standard pictures.
CR 10261, Iron and steel — Review of available methods of chemical analysis.
EN ISO 377, Steel and steel products — Location and preparation of samples and test pieces for mechanical
testing.
EN ISO 14284, Steel and iron — Sampling and preparation of samples for the determination of chemical
composition (ISO 14284:1996).
EN ISO 3887, Steels — Determination of depth of decarburization.
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
oil hardened and tempered spring steel wire
wire that is heat treated in line in the following way: it is first transformed into austenite, quenched in oil or
similar quenching medium, followed immediately by tempering by heating to the appropriate temperature
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oSIST prEN 10270-2:2008
prEN 10270-2:2008 (E)
4 Classification and designation
4.1 Classification
This standard deals with all types of hardened and tempered spring steel wire. The grade for normal
applications made from unalloyed or alloyed steel has the abbreviation FD and is intended for static
applications.
Spring steel wire for medium fatigue levels, such as required for some clutch springs from unalloyed or alloyed
steel, has the abbreviation TD.
Spring steel wire from unalloyed steel or alloyed steel intended for use under severe dynamic duty such as for
valve springs or other springs with similar requirements has the abbreviation VD.
The diameter ranges for the various wire grades are shown in Table 1.
Table 1 — Spring wire grades
Tensile strength Static Medium fatigue High fatique
Low tensile strength FDC TDC VDC
Medium tensile strength FDCrV TDCrV VDCrV
High tensile strength FDSiCr TDSiCr VDSiCr
Very high tensile strength FDSiCrV TDSiCrV VDSiCrV
Diameter range (mm) 0,50 - 17,00 0,50 - 10,00 0,50 - 10,00
Medium and high fatigue grades TD and VD are characterized by high steel cleanliness, specific chemical,
mechanical and technological parameters and a well defined surface condition in relation to the allowable
depth of surface defects and decarburization.
The static grade FD is characterized by its chemical, mechanical and technological characteristics as well as
by a specified surface condition concerning surface defects and decarburization.
4.2 Designation
For products supplied according to this standard the designation shall state the following in the following
order:
 the term: spring wire;
 the number of this European Standard: EN 10270-2;
 the abbreviation for the wire grade (see Table 1);
 the required nominal diameter selected from Table 4 or Table 5;
EXAMPLE Standard designation of an oil hardened and tempered steel spring wire according to this standard of wire
grade VDC with a nominal diameter of 2,50 mm:
Spring wire EN 10270-2 - VDC - 2,50.
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oSIST prEN 10270-2:2008
prEN 10270-2:2008 (E)
5 Information to be supplied by the purchaser
The purchaser shall clearly state in his enquiry or order the product and following information:
a) the desired quantity;
b) the number of this European Standard: EN 10270-2;
c) wire grade (see 4.1);
d) the nominal wire diameter;
e) the form of delivery and unit mass;
f) the type of inspection document;
g) any particular agreement made.
EXAMPLE 5 t spring wire EN 10270-2 - VDC - 2,50
in coils of about 300 kg
inspection document EN 10204 - 3.1.B.
6 Requirements
6.1 Form of delivery
6.1.1 Oil hardened and tempered wire shall be supplied in coils, on spools or in cut lengths. The wire in
coils or on spools shall form one continuous length. Wire in coil may also be supplied on carriers containing
one or more coils.
For "VD" and "TD" grades no welds are permitted after the heat treatments preceding the final drawing
operation; for "FD" grades no welds shall be made at finished size unless agreed otherwise between the
parties.
6.1.2 The supplied wire units shall be tightly bound to ensure that wire spiral waps do not spring out
unforeseen. The starting end shall be marked and at the coil ends the wire shall be covered with a protective
cap.
6.2 Surface finish
The wire shall be protected against corrosion and mechanical damage. Unless otherwise specified the wire
shall be delivered in slightly oiled condition.
6.3 Chemical composition
The steel is characterized by the heat analysis which shall be in accordance with the values of Table 2. The
permissible deviation of the product analysis from the limiting values of heat analysis shall be in accordance
with Table 3.
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oSIST prEN 10270-2:2008
prEN 10270-2:2008 (E)
6.4 Non metallic inclusions
The "VD" grades shall be checked for maximum size of inclusion according to ENV 10247. The allowable level
of inclusions shall be agreed between the parties at the enquiry and order.
6.5 Mechanical properties
For tensile strength R and reduction in area after fracture (Z) the wire grades shall satisfy the values listed in
m
Tables 4 and 5. Reduction of area is measured only for size 1,00 mm and above (see Tables 4, 5 and 11).
The range of the tensile strength values within a coil/reel shall not exceed 50 MPa for the grades "VD",
60 MPa for the grades "TD" and 70 MPa for the grades "FD".
Table 2 — Chemical composition, % by mass
a
Grade C Si P S Cu Cr V
Mn
  max. max. max.
b
VDC 0,60-0,75 0,15-0,30 0,50-1,00 0,020 0,020 0,06
VDCrV 0,62-0,72 0,15-0,30 0,50-0,90 0,025 0,020 0,06 0,40-0,60 0,15-0,25
VDSiCr 0,50-0,60 1,20-1,60 0,50-0,90 0,025 0,020 0,06 0,50-0,80
VDSiCrV 0,50-0,70 1,20-1,65 0,40-0,80 0,020 0,020 0,06 0,50-1,00 0,10-0,25
b
TDC 0,60-0,75 0,10-0,35 0,50-1,20 0,020 0,020 0,10
TDCrV 0,62-0,72 0,15-0,30 0,50-0,90 0,025 0,020 0,10 0,40-0,60 0,15-0,25
TDSiCr 0,50-0,60 1,20-1,60 0,50-0,90 0,025 0,020 0,10 0,50-0,80
TDSiCrV 0,50-0,70 1,20-1,65 0,40-0,80 0,020 0,020 0,10 0,50-1,00 0,10-0,25
b
FDC 0,60-0,75 0,10-0,35 0,50-1,20 0,030 0,025 0,12
FDCrV 0,62-0,72 0,15-0,30 0,50-0,90 0,030 0,025 0,12 0,40-0,60 0,15-0,25
FDSiCr 0,50-0,60 1,20-1,60 0,50-0,90 0,030 0,025 0,12 0,50-0,80
FDSiCrV 0,50-0,70 1,20-1,65 0,40-0,80 0,030 0,025 0,12 0,50-1,00 0,10-0,25

a
Manganese may be ordered with restricted range, but with a minimum range of 0,20 %.

b
For heavy wire diameter (above 8,5 mm) chromium may be added up to 0,30 % for proper through hardening.
Table 3 — Permissible deviation of the product analysis from the limiting values for the heat analysis
Chemical element Wire grade Permissible deviation
 % by mass
C All
± 0,03
Si SiCr, SiCrV ± 0,05
other grades
± 0,03
Mn All ± 0,04
P All + 0,005
S All + 0,005
Cu All + 0,02
Cr All
± 0,05
V All ± 0,02

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oSIST prEN 10270-2:2008
prEN 10270-2:2008 (E)
Table 4 — Mechanical and technological properties and quality requirements for wire grades FDC, FDCrV, FDSiCr and FDSiCrV
1 2 3 4 5 6 7 8 9 10 11 12 13 14
a
Tensile strength R Minimum reduction in area after fracture Z for wire grades Minimum number of torsions for wire grades
Nominal wire Permissible m
b b b b
diameter deviations
FDC FDCrV FDSiCr FDSiCrV FDC FDCrV FDSiCr FDSiCrV FDC FDCrV FDSiCr FDSiCrV
mm mm MPa MPa MPa MPa % % % %
d = 0,50
1900 to 2000 to 2100 to   _ _ _ _
2100 2200 2300
0,50 < d ≤ ± 0,010 1900 to 2000 to 2100 to _ _ _ _ _
0,60 2100 2200 2300
0,60 < d ≤ 1900 to 2000 to 2100 to
0,80 2100 2200 2300
0,80 < d ≤ ± 0,015 1860 to 1960 to 2100 to
1,00 2060 2160 2300
1,00 < d ≤ 1810 to 1900 to 2070 to 2150 to
1,30 2010 2100 2260 2290
1,30 < d ± 0,020 1790 to 1870 to 2060 to 2140 to
≤ 1,40 1970 2070 2250 2280
1,40 < d 1760 to 1840 to 2040 to 2130 to
≤ 1,60 1940 2030 2220 2270
1,60 < d ≤ 1720 to 1790 to 2000 to 2130 to   To be agreed To be To be To be
2,00 1890 1970 2180 2270 agreed agreed agreed
2,00 < d ≤ ± 0,025 1670 to 1750 to 1970 to 2090 to 45 45 45 45 upon upon upon upon
2,50 1820 1900 2140 2230
2,50 < d 1640 to 1720 to 1950 to 2090 to
≤ 2,70 1790 1870 2120 2230
2,70 < d 1620 to 1700 to 1930 to 2090 to
≤ 3,00 1770 1850 2100 2230
3,00 < d ≤ ± 0,030 1600 to 1680 to 1910 to 2080 to
3,20 1750 1830 2080 2220
3,20 < d ≤ 1580 to 1660 to 1900 to 2060 to 42 42 42 42
3,50 1730 1810 2060 2200
3,50 < d ≤ 1550 to 1620 to 1870 to 2060 to
4,00 1700 1770 2030 2200
"to be concluded"
...