ISO 5003:2016

DRAFT INTERNATIONAL STANDARD
ISO/DIS 5003
ISO/TC 17/SC 15 Secretariat: SAC
Voting begins on: Voting terminates on:
2014-10-08 2015-01-08
Vignole railway rails 43 kg/m and above
Rails Vignole et profils spéciaux pour aiguillages en acier non traité pour chemins de fer — Spécifications
techniques de livraison
ICS: 45.080
THIS DOCUMENT IS A DRAFT CIRCULATED
FOR COMMENT AND APPROVAL. IT IS
THEREFORE SUBJECT TO CHANGE AND MAY
NOT BE REFERRED TO AS AN INTERNATIONAL
STANDARD UNTIL PUBLISHED AS SUCH.
IN ADDITION TO THEIR EVALUATION AS
BEING ACCEPTABLE FOR INDUSTRIAL,
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STANDARDS MAY ON OCCASION HAVE TO
BE CONSIDERED IN THE LIGHT OF THEIR
POTENTIAL TO BECOME STANDARDS TO
WHICH REFERENCE MAY BE MADE IN
Reference number
NATIONAL REGULATIONS.
ISO/DIS 5003:2014(E)
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. ISO 2014

ISO/DIS 5003:2014(E)
Copyright notice
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ii © ISO 2014 – All rights reserved

ISO/DIS 5003
Contents Page
Foreword . v
1  Scope . 1
2  Normative references . 1
3  Terms and Definitions . 1
4  Information to be supplied by the purchaser . 2
5  Test methods . 3
5.1 Test items, testing frequency and test methods . 3
5.2  Chemical composition . 4
5.3  Hydrogen content . 4
5.4 Total oxygen content . 4
5.5 Tensile test . 4
5.6 Hardness . 5
5.7 Microstructure . 5
5.8 Decarburization . 5
5.9 Nonmetallic inclusions . 5
5.10 Macrostructure . 6
5.11 Ultrasonic test . 6
5.12 Residual stress . 6
5.13 Fracture toughness (K ) . 7
Ic
5.14  Fatigue crack growth rate . 7
5.15 Fatigue test . 8
5.16 Variation of centre line running surface hardness of heat treated rails . 8
6 Tolerances for dimension, shape, length and weight . 8
6.1 Dimension, shape and length tolerance . 8
6.2 Straightness, surface flatness and twist . 9
6.3 Length . 9
6.4 Drilling holes . 9
6.5 Weight . 9
7 Technical requirements . 14
7.1 Manufacture methods . 14
7.2  Chemical composition . 14
7.3 Mechanical properties. 16
7.4  Microstructure . 18
7.5  Decarburization . 18
7.6 Nonmetallic inclusions . 18
7.7 Macrostructure . 19
ISO/ DIS 5003
7.8 Ultrasonic test . 19
7.9 Surface quality . 19
7.10 Residual stress . 20
7.11 Fracture toughness . 20
7.12 Fatigue crack growth rate . 21
7.13 Fatigue test . 21
8  Inspection requirements . 21
8.1 Inspection and acceptance . 21
8.2 Retest and justification . 21
9  Identification . 21
9.1  Branding . 21
9.2  Hot stamping . 22
9.3  Cold stamping . 22
9.4 Other identification . 22
10  Certification . 22
11  Quality assurance system . 23
11.1  Quality system . 23
Annex A (normative) Steel grades . 36
Annex B (normative) Method for determination of tensile strength and elongation for hot rolled
rails by a correlation . 37
Annex C (normative) Microscopic examination of rail steels using standard diagrams to assess
the content of non-metallic inclusions . 39
Annex D (informative) 60E1 Rail profile . 45
Annex E (normative) Method for the determination of rail foot surface longitudinal residual
stresses . 46
Annex F (normative) Standard test method for the determination of the plane strain fracture
toughness (KIc) of rails . 49
Annex G (normative) Profile and drilling gauges . 55
Annex H (normative) Standard diagrams for the check of the macrostructure of rails in
accordance to ISO4969 . 67
Annex I (normative) Limiting sulfur prints . 76
Bibliography . 90

iv © ISO 2002 – All rights reserved

ISO/DIS 5003
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies
(ISO member bodies). The work of preparing International Standards is normally carried out through ISO
technical committees. Each member body interested in a subject for which a technical committee has been
established has the right to be represented on that committee. International organizations, governmental and
non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the
International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. Draft International Standards
adopted by the technical committees are circulated to the member bodies for voting. Publication as an
International Standard requires approval by at least 75 % of the member bodies casting a vote.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. ISO shall not be held responsible for identifying any or all such patent rights.
International Standard ISO 5003 was prepared by Technical Committee ISO/TC 17, Steel, Subcommittee
SC 15, Railway rails, rail fasteners, wheels and wheelsets.

ISO/ DIS 5003
Vignole railway rails 43 kg/m and above
1  Scope
This standard specifies the terms and definitions, information to be supplied by the purchaser，
tolerances for dimensions, length, technical requirements, inspection rules, identification,
certification, quality assurance system for hot rolled and heat treated steel rails for railway.
This standard specifies Vignole railway rails of 43 kg/m and greater linear mass, for conventional
and high speed railway track usage.
Nineteen pearlitic steel grades are specified covering hardness range of 200 to 400 HBW and
include non heat treated carbon manganese steels, non heat treated alloy steels, and heat
treated carbon manganese and low alloy steels.
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.
ISO 404  Steel and steel products – General technical delivery requirements
ISO 1099 Metallic materials – Fatigue testing – Axial force controlled method
ISO 3887  Steels – Determination of depth of decarburization
ISO 4967  Steel – Determination of content of nonmetallic inclusions-Micrographic method using
standard diagrams
ISO 4969  Steel – Macroscopic examination by etching with strong mineral acids
ISO 6892-1 Metallic materials – Tensile testing – Part 1: Method of test at room temperature
ISO 6506-1 Metallic materials – Brinell hardness test – Part 1: Test method
ISO 4968  Steel – Macroscopic examination by sulphur print (Baumann method)
ISO 14284 Steel and iron-Sampling and preparation of samples for the determination of chemical
composition
ISO 12108 Metallic materials – Fatigue testing – Fatigue crack growth method
ASTM E45 Standard test methods for determining the inclusion content of steel
ASTM E399 Standard Test Method for Linear-Elastic Plane-Strain Fracture Toughness K of
lc
Metallic Materials
3  Terms and Definitions
3.1
heat
liquid steel melt tapped out of a converter or electric arc furnace which includes after continuous
casting a given number of blooms relating to the weight of the heat and the extension of the
mixing zone.
Note: In the case of sequence casting the blooms belonging to the mixing zone should be clearly
defined.
ISO/ DIS 5003
3.2
sequence
Any number of heats, of the same steel grade, which undergo continuous casting in tundishes.
Note: Tundishes can be used in parallel if the caster has many strands.
3.3
heat treated rail
Rail that has undergone accelerated cooling from austenitizing temperature during the
metallurgical transformation period.
3.4
off-line heat treated rail
All rolled rail that has undergone re-austenitization for heat treatment purposes.
3.5
on-line heat treated rail
Heat treated rail that has not undergone re-austenitization after rolling.
3.6
rolling process
Process between the blooms leaving the heating furnace and exiting the finishing pass.
3.7
isothermal treatment process
Process whereby blooms are held for a period of time at an elevated temperature for diminishing
the hydrogen content.
NOTE 1 For maximum efficiency this is as near to (but below) the pearlite to austenite transformation
temperature as is practically possible.
NOTE 2 This process is sometimes referred to as sub critical diffusion annealing.
3.8
rail running surface
curved surface of the rail head. Area between both gauge corners (transition points of the head
inclination and the first head radius).
4  Information to be supplied by the purchaser
The purchaser shall provide the supplier with the following information at the time of enquiry or
order:
a) the rail profile (by referring to any other standard or submitting a drawing);
b) the steel grade (see 7.2 and Annex A);
c) the profile tolerances (see Table 2)
d) the straightness class ‘A’ or ‘B’ of rail (see Table 3);
e) the nonmetallic inclusion determination method and if applicable: the class ‘1’ or ‘2’ of
rail (see Table 11);
f) the determination of the macrostructure (see 5.10);
g) the lengths of rail (see Table 2 and 6.3);
h) undrilled or drilled rail ends to take fish bolts, and location and dimensions of holes
when required (see Table 2 and 6.4);
2 © ISO 2002 – All rights reserved

ISO/DIS 5003
i) paint code requirements (see 9.4.4).
5  Test methods
5.1 Test items, testing frequency and test methods
Test items, sampling position, sampling numbers and test methods shall be as given in Tables 1a
and 1b.
Table 1a Testing frequency for acceptance testing
Relevant
Test items Hot-rolled rails Heat-treated rails
sub-clause
Chemical
One per heat One per heat 5.2
composition
One per heat
One per heat
Hydrogen 5.3
(2 tests from first heat in
( 2 tests from first heat in sequence)
sequence)
a a
Total oxygen One per sequence One per sequence 5.4
a,b, d a,c
Tensile One per heat One per heat 5.5
a,b a,c
Hardness One per heat One per heat 5.6
Not required for grades HR200,
HR220,HR235 and HR260A.
One per 100 tonnes of
Microstructure 5.7
a,c
heat treated rail
One per 1000 tonnes or part thereof for
grades HR260B,HR280,HR310A,
a, b
HR310B,HR320,HR325
a,b
One per 500 tonnes or
Decarburization One per 1000 tonnes or part thereof 5.8
a,c
part thereof
Nonmetallic b b or c
One per sequence One per sequence 5.9
inclusions
One per 500 tonnes or
a,b
Macrostructure One per 500 tonnes or part thereof 5.10
a,b or c
part thereof
Dimension Whole length Whole length 6.1
straightness Whole length Whole length 6.2
Surface quality Whole length Whole length 7.9
Ultrasonic test Whole length Whole length 5.11
a. Samples shall be taken at random but only rails from blooms outside the mixing zone
between heats when continuously cast in sequence.
b. Samples shall be cut after rolling.
c. Samples shall be cut after heat-treating for heat treated rails.
d. one calculation per heat / one testing per 2,000 tonnes if agreed between purchaser and
manufacturer
ISO/ DIS 5003
Table 1b Testing frequency for periodic tests
Test items Hot-rolled rails and Heat-treated rails Relevant sub-clause
Residual stress 5.12
Tests shall be done for all grades at least
once every 5 years or after any relevant
Fracture toughness(K) 5.13
Ic
change in the production process. The
manufacturer shall only carry out testing on
Fatigue crack growth rate 5.14
a 60 kg/m profile or the heaviest section
produced.
Fatigue test 5.15
Longitudinal hardness test Heat-treated rails 5.16

5.2  Chemical composition
The chemical composition shall be determined on the liquid.
When the solid chemical composition shall be checked on the requirement of the purchaser, this
shall be carried out at the position of the tensile test piece (see Figure 1).
5.3  Hydrogen content
The hydrogen content of the liquid steel shall be measured by determining pressure of hydrogen
in the steel using an on-line immersion probe system or the method agreed between the
purchaser and manufacturer.
At least two liquid samples shall be taken from the first heat of any sequence using a new tundish
and one from each of the remaining heats and analyzed for hydrogen content (see Table 1a).
The first sample from the first heat in a sequence shall be taken from the tundish at the time of
the maximum hydrogen concentration.
When testing of rails is required rail samples shall be taken at the hot saw at a frequency of one
per heat at random. However on the first heat in a sequence, the rail sample shall be from the
last part of a first bloom teemed on any strand. Hydrogen determination shall be carried out on
samples taken from the centre of the rail head, and determined by automatic machine.
5.4 Total oxygen content
The total oxygen content can be determined in the liquid or solid.
If the total oxygen content is determined from the solid rail head, the testing positions are shown
in Figure 2.
5.5 Tensile test
Test samples shall be taken from the rail head as shown in Figure 1.
The tensile properties shall be determined in accordance with ISO 6892-1 by using a round
tensile test piece with the dimensions as follows:
- diameter 10 mm;
- original gauge length 50 mm.
In the case of dispute, the tensile test pieces shall be maintained at a temperature of 200°C for 6
h before testing.
4 © ISO 2002 – All rights reserved

ISO/DIS 5003
For hot rolled rails, the tensile strength and elongation may be determined as agreed between
purchaser and manufacturer by a correlation to the chemical composition based on the statistic
data analysis. The method to be applied is shown in Annex B.
5.6 Hardness
5.6.1 General requirements
Brinell hardness tests (HBW) shall be carried out in accordance with ISO 6506-1. The method
used is on the discretion of the manufacturer.
In case of dispute, test shall be done using HBW 2.5/187.5.
5.6.2 Surface hardness
The surface hardness shall be tested for position RS as shown in Figure 3.
The surface hardness shall be tested on the centre line of the rail head crown. 0.5 mm shall be
ground from the running surface before a hardness impression is made.
5.6.3 Internal hardness
For heat treated rails the internal hardness shall be tested in accordance with ISO 6506-1 at the
testing positions shown in Figure 3.
The internal hardness of heat-treated rails of any steel grade shall be determined on a transverse
specimen cut from the end of the rail. The specimen shall be ground or milled so that the
transverse surfaces are parallel.
5.7 Microstructure
The microstructure testing position in the rail head shall be as shown in Figure 1, and shall be
determined at a magnification of ×500.
5.8 Decarburization
Decarburisation depth shall be assessed by means of a hardness test using HBW 2.5/187.5
indentation. The test shall be performed at three points in the centre of the rail crown after
minimal preparation of the rail head surface (less than 0.2mm material removed). None of the
hardness test results shall be more than 7 points lower than the minimum hardness of the
specified grade (e.g. 253HBW for 260 grade rail).
As an alternative or in the case of dispute decarburisation depth shall be measure
metallographically.The testing position in the surface of rail head shall be as shown in Figure 4.
The test shall be made to measure the depth of closed ferrite network in accordance with ISO
3887.Photomicrographs showing examples how to determine the depth of decarburization are
shown in Figure 5.
5.9 Nonmetallic inclusions
5.9.1 General requirements
Samples shall be taken from one of the last blooms of the last heat of the sequence. From each
sample 2 specimens shall be tested.
The nonmetallic inclusions testing position in the rail head is shown in Figure 6.
5.9.2 Testing methods
ISO/ DIS 5003
The test shall comply with the method shown in Annex C.
As agreed between purchaser and manufacturer (see 4e), alternative methods may be used:
- Method A in standard ISO 4967,
- Method A in standard ASTM E45.
5.10 Macrostructure
Macrostructure of transverse rail sections shall be tested in accordance with ISO 4969 or ISO
4968, as agreed between purchaser and manufacturer (information given by the purchaser in 4f).
5.11 Ultrasonic test
5.11.1 Testing area
The minimum cross-sectional area examined by the ultrasonic technique shall be:
at least 70 % of the head;
at least 60 % of the web;
and the area of the foot to be tested shall be as shown in Figure 7.
By convention these areas are based on projecting the nominal crystal size of the probe. The
head shall be tested from both sides and from the running surface.
5.11.2 Sensitivity requirements
The sensitivity levels of the automated equipment used shall be a minimum of 4 dB greater than
the level required to detect the reference reflectors described in 5.11.3. A rail giving an echo
referring to a possible defect shall be separated by means of an automatic trigger/alarm level
combined with a marking and/or sorting system. For possible retesting, the test sensitivity shall
be increased to 6 dB instead of 4 dB.
The system shall incorporate continuous monitoring of interface signals and, if present, backwall
echo signals.
5.11.3 Calibration rails
There shall be a calibration rail for each profile to be tested ultrasonically. The positions of the
artificial defects are given for the rail head, web and foot of the 60E1 profile (see Annex D) in
Figures 8, 9 and 10 respectively. Calibration rails for other profiles with calibration defects similar
to those in accordance with Figures 8, 9 and 10 for 60E1 shall be available.
Other methods of calibration may be used but these methods shall be equivalent to that
described above.
5.12 Residual stress
5.12.1 Test sample rail
The manufacturer shall only carry out testing on a 60 kg/m profile or the heaviest section
produced. For residual stress tests there shall be 6 sample rails, which be taken from finished
6 © ISO 2002 – All rights reserved

ISO/DIS 5003
roller straightened rails, and test pieces shall be taken from the full roller straightened part of the
rail.
5.12.2 Test pieces
Each of the 6 test pieces from the rail section shall be 1000 mm in length.
5.12.3 Test method
The residual stresses in the rail foot shall be determined in accordance with Annex E.
5.13  Fracture toughness (K )
Ic
5.13.1 Test sample
The rails used for this test shall be of the same profile as used for 5.12.
Three rail test pieces shall be taken from the full roller straightened part of rails from three
different heats and different strands.
From each of the three rail test pieces, a minimum of 5 samples shall be produced.
These samples shall not be subject to any further mechanical or thermal treatment.
5.13.2 Test pieces test method
Fracture toughness test shall be performed in accordance with Annex F.
5.14  Fatigue crack growth rate
5.14.1 Test sample rail
The rails used for this test shall be of the same profile as used for 5.12.
Three rail test pieces shall be taken from the full roller straightened part of rails from three
different heats and different strands.
From each of the three rail test pieces, a minimum of 3 samples shall be produced.
These samples shall not be subject to any further mechanical or thermal treatment.
5.14.2 Test pieces
A three point bend, single edge notch test piece, of the dimensions and location within the rail
shown in Figure 11 shall be used.
5.14.3 Test method
Tests shall be carried out in accordance with the general requirements of ISO 12108.
5.14.4 Number of tests and test conditions
A minimum of 3 tests from each sample rail shall be performed under the following conditions:
— test temperature shall be within the range +15℃ to +25℃;
— R = 0.5 (R = minimum cyclic load/maximum cyclic load);
ISO/ DIS 5003
— 3 point bend test piece loading span shall be 4 W (see Figure 11);
— cyclic loading frequency shall be within the range 15 Hz to 40 Hz;
— environment: laboratory air.
5.15 Fatigue test
5.15.1 Test sample rail
The rails used for this test shall be of the same profile as used for 5.12.
Three rail test pieces shall be taken from the full roller straightened part of rails from three
different heats and different strands.
From each of the three rail test pieces, a minimum of 3 samples shall be produced.
These samples shall not be subject to any further mechanical or thermal treatment.
5.15.2 Test pieces
The test pieces shall be machined from the sample rail as shown in Figure 12.
5.15.3 Test method
Constant amplitude fatigue tests shall be carried out in accordance with ISO 1099.
5.15.4 Number of tests and test conditions
A minimum of 3 test pieces shall be tested from each sample rail under the following conditions:
— test temperature shall be within the range + 15°C to + 25°C;
— control variable shall be axial strain amplitude;
— strain cycle shall be symmetrical about the initial, zero load.
5.16 Variation of centre line running surface hardness of heat treated rails
This clause only applies to heat treated rails.
For the longest length of rail produced by the manufacturer, a one metre length of rail shall be
taken from each end and at 20 m intervals from one end of the rail. These shall be hardness
tested (HBW) in accordance with ISO 6506-1 along their length at 25 mm intervals on the
centreline of the running surface after 0.5 mm has been ground away. The hardness results shall
be no more than ± 15 HBW from the mean result obtained.
6 Tolerances for dimension, shape, length and weight
6.1 Dimension, shape and length tolerance
The reference points of the profile and the gauges shall be as given in Table 2a. The profile
tolerances shall be given by purchaser (4c).
Note: The figures show in table 2a are informative for 60E1 rail profile.
8 © ISO 2002 – All rights reserved

ISO/DIS 5003
6.2 Straightness, surface flatness and twist
Flatness testing of the body shall be performed automatically.
Tolerances for straightness, surface flatness and twist shall meet the requirements given in Table
3. Unless otherwise agreed, rails < 54 kg/m are delivered with class B tolerances.
If the rail shows evidence of twist, this shall be checked in accordance with Figure 13 by inserting
feeler gauges between the base of the rail and the rail skid nearest the rail end with the rail being
laid head up on an inspection bed. If the gap exceeds 2.5 mm the rail shall be rejected.
Rotational twist in the end meter of the rail as measured by the gauge illustrated in Figure 14,
shall not exceed 0.2
Rejected rails may be subject to only one roller re-straightening.
In cases of dispute on the results of the automatic technique, rail flatness shall be verified using a
straight edge as shown in Table 3.
6.3 Length
The cut length and shorten length of rails shall be agreed by purchaser and manufacture (see 4g).
6.4 Drilling holes
The tolerances for hole dimension and position shall be as given in Table 2b.
The chamfer angle of drilled holes shall be 45° and 0.8 to 2.0 mm in depth.
6.5 Weight
Rails shall be delivered in theoretical weight. The density of 7.85g/cm shall be applied to
calculate the rail theoretical weight.

ISO/ DIS 5003
Table 2a Tolerances for profile dimension
* Profile class
Reference points
60E1 rail profile (Annex D)
Gauge, figure
(see Figure D.1)
(dimensions in mm,informative)
number
(see Annex G)
Location/property Symbol X Y
Height of rail *H ±0.6 ±0.8 G.3
Width of rail head *WH ±0.5 ±0.5 G.4

Crown profile
+0.6 +0.6
– Class A straightness
*C G.5
-0.3 -0.3
– Class B straightness
±0.6 ±0.6
Rail asymmetry *AS ±1.2 ±1.5 G.6 and G.7

Height of fishing
G.8
±0.5 ±0.5
– Class A straightness
*HF
– Class B straightness ±0.6 ±0.6
+1.0 +1.0
Web thickness *WT G.9
-0.5 -0.5
+1.5
Width of rail foot *WF ±1.0 G.10
-1.0
+0.75 +0.75
Foot toe thickness *TF G.11
-0.5 -0.5
Foot base concavity ≤0.3 ≤0.3

10 © ISO 2002 – All rights reserved

ISO/DIS 5003
Table 2b Tolerances for cutting, drilling and length
Profile class
Gauge, figure
60E1 rail profile (Annex D)
(dimensions in mm,informative) number
(see Annex G)
X Y
0.8 mm in any
0.6 mm in any direction
direction
Squareness of ends
Diameter ±0.7 ±0.8 G.12
Position
The horizontal position of the holes is checked using
Centring and
a gauge as shown in Figure G.12 which has a stop
positioning of the holes
designed to come into contact with the end of the rail
vertically and
and pins designed to enter the holes.
horizontally
The diameter of the pins for horizontal and vertical
clearances is smaller than the diameter of the holes
by:
- 1,0 mm for holes less than or equal to 30 mm in
diameter;
Bolts
- 1,4 mm for holes greater than 30 mm in diameter.  G.12, G.13
The distances between the centre lines of the pins
and the stop are equal to the nominal distances from
the centre line of the holes to the
end of the rail.
The gauge pins shall be able to enter the holes at the
same time while the stop is touching the end of the
rail.
The vertical centring of the holes can be checked
using a gauge as shown in Figure G.13.
The side of the hole, left or right, is determined by
proceeding from the side with the relief markings.
rails drilled on both
±6 ±6
ends ≤25m
a
rails undrilled ≤25m ±10 ±10
Length
rails undrilled or
±1mm/1m ±1mm/1m
drilled one end >25m
a
The given rail lengths apply for + 20°C. Measurements made at other temperatures are to be
corrected to take into account expansion or contraction of the rail.
ISO/ DIS 5003
Table 3  Straightness, surface flatness and twist tolerances
Class B
Class A
Location/Dimensional properties
d L
d L
d
End “E” 2m 1.5m
≤0.4mm 2m ≤0.5mm 1.5m
b
Vertical straightness-up（V ） and
f
≤0.3mm 1m
and
Vertical straightness-down
a,c and
Ends
e≤0.2mm
（V） e≤0.2mm
d
≤0.6mm 2m ≤0.7mm 1.5m
and
b
Horizontal straightness（H ）
f
≤0.4mm 1m
d
Length of overlap 2m 1.5m
e e
Vertical flatness（V）
≤0.3mm 2m ≤0.4mm 1.5m
a,c
Overlap
e e
Horizontal flatness（H） ≤0.6mm 2m ≤0.6mm 1.5m

e e d
≤0.3mm 3m ≤0.4mm 3m
Vertical flatness（V） and and
a,c
e e
Body
≤0.2mm 1m ≤0.3mm 1m
e
e
≤0.6mm 1.5m
Horizontal flatness（H） ≤0.45mm 1.5m

Sweep
g g
Upsweep and downsweep 10mm 10mm
(whole rail)
ISO/DIS 5003
Table 3  (continued)
e
Location/Dimensional properties Class A Class B
See 6.2 and Figure 13
Whole rail Max. gap of 2.5mm
Twist
Max. rotational twist of 0.2° and max. relative See 6.2 and Figure 14
End (1m)
twist of 0.0035×c
a. b.
c. Automatic measurement equipment shall measure as much of the rail as possible but, at least the body. If the whole rail satisfies the body
specifications, then measurement of end and overlap is not mandatory.
d. Automatic measurement techniques are complex and are therefore difficult to define but the finished rail flatness shall be capable of being verified
by straight edge as shown in the above drawings.
e. 95 % of delivered rails shall be within limits specified, with 5 % of rails allowed outside the tolerances by 0.1 mm.
f. Reference L sliding over end E.
g. The ends of the rails shall not be up more than 10 mm when the rail is on its foot or on its head when standing on an inspection bed.
ISO/ DIS 5003
7 Technical requirements
7.1 Manufacture methods
7.1.1 Blooms made from basic oxygen steel or electric arc furnace steel that has been
secondary ladle arc refined, vacuum degassed and continuously cast, shall be used for the
manufacture of rails.
7.1.2 The manufacturer shall operate a procedure for the effective removal of scale during the
rolling process.
7.1.3 The cross-sectional area of the rail shall not exceed one ninth that of the bloom from
which the rail is rolled.
7.1.4 Rail straightening shall be by a two stage roller straightening process which straightens
the rail about its XX and YY axes as defined in the rail profiles. End deviations or a localized
deviation on the rail may be corrected using pressing.
7.2  Chemical composition
7.2.1 General
The liquid chemical composition shall fulfil the requirements of Tables 4 and 5, and liquid
residual elements shall fulfil the requirements of Table 6.
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The content of Nitrogen shall not exceed 90×10 % in the liquid for all steel grades.
Table 4 Chemical composition of hot-rolled (HR) rails (in mass %)
P S Al
t
Steel grade C Si Mn Cr V
Max. Max. Max.
HR200 0.40-0.600.15-0.58 0.70-1.20 0.035 0.025 ≤0.15 0.004 ≤0.030
HR220 0.50-0.600.20-0.60 1.00-1.25 0.025 0.025 ≤0.15 0.004 ≤0.030
HR235 0.63-0.750.15-0.30 0.70-1.10 0.030 0.025 ≤0.15 0.004 ≤0.030
HR260A 0.62-0.80 0.15-0.58 0.70-1.20 0.025 0.025 ≤0.15 0.004 ≤0.030
HR260B 0.55-0.75 0.15-0.60 1.30-1.70 0.025 0.025 ≤0.15 0.004 ≤0.030
0.04-
HR280 0.71-0.800.50-0.80 0.70-1.05 0.025 0.025 ≤0.15 0.004
0.12
HR310A 0.74-0.86 0.10-0.60 0.75-1.25 0.020 0.020 ≤0.30 0.004 ≤0.030
HR310B 0.72-0.82 0.10-0.50 0.80-1.10 0.020 0.020 0.25-0.40 0.004
≤0.030
HR320 0.60-0.800.50-1.10 0.80-1.20 0.020 0.025 0.80-1.20 0.004 ≤0.18
HR325 0.72-0.820.10-1.00 0.70-1.25 0.020 0.020 0.40-0.70 0.004 ≤0.030

ISO/DIS 5003
Table 5 Chemical composition of heat-treated (HT) rails (in mass %)
P S Al
t
Steel grade C Si Mn Cr V
max. max. max.
HT320 0.72-0.82 0.10-0.55 0.70-1.10 0.030 0.020 ≤0.20 0.004 ≤0.030
HT330 0.72-0.82 0.10-0.65 0.80-1.20 0.030 0.020 ≤0.25 0.004 ≤0.030
HT340 0.71-0.80 0.50-0.80 0.70-1.05 0.025 0.020 0.004 0.04-0.12
≤0.15
HT350A 0.72-0.80 0.15-0.58 0.70-1.20 0.020 0.025 ≤0.15 0.004 ≤0.030
HT350B 0.72-0.80 0.15-0.58 0.70-1.20 0.020 0.025 ≤0.30 0.004 ≤0.030
HT370A 0.74-0.86 0.10-0.60 0.75-1.25 0.020 0.020 ≤0.30 0.004 ≤0.030
HT370B 0.72-0.82 0.10-1.00 0.70-1.25 0.020 0.020 0.40-0.70 0.004 ≤0.030
HT370C 0.70-0.82 0.40-1.00 0.70-1.10 0.020 0.020 0.40-0.60 0.004 ≤0.030
HT400 0.90-1.05 0.20-0.60 1.00-1.30 0.020 0.020 ≤0.30 0.004 ≤0.030

Table 6 Maximum residual elements (%)
Steel grade Nb Mo Cu Ni Sn Sb Ti Cu+10Sn others
HR200,HR220
0.01 0.02 0.15 0.10 0.030 0.020 0.025 0.35 0.35(Cr+Mo+Ni+Cu+V )
HR235,HR260A,HR260B
HR280 0.01 0.02 0.15 0.10 0.030 0.020 0.025 0.35 0.35(Cr+Mo+Ni+Cu)
HR310A 0.01 0.02 0.15 0.10 0.030 0.020 0.025 0.35 0.20(Mo+Ni+Cu+V)
HR310B,HR325 0.01 0.02 0.40 0.15 0.030 0.020 0.025- -
HR320 0.01 0.02 0.15 0.10 0.030 0.020 0.025 0.35 0.16(Ni+Cu)
HT320,HT330,HT350B 0.04 0.02 0.15 0.10 0.030 0.020 0.025 0.35 0.20(Mo+Ni+Cu+V)
HT370A,HT370C,HT400
HT340 0.04 0.02 0.15 0.10 0.030 0.020 0.025 0.35 0.35(Cr+Mo+Ni+Cu)
HT350A 0.04 0.02 0.15 0.10 0.030 0.020 0.025 0.35 0.25(Cr+Mo+Ni+Cu+V )
HT370B 0.04 0.02 0.40 0.15 0.030 0.020 0.025- -
7.2.2 The solid chemical composition tolerances shall conform to the requirements of Table 7.

ISO/ DIS 5003
Table 7 Solid chemical composition tolerance on the upper and lower limits (%)
Elements Under (Minimum)
Over （Maximum）
C 0.02 0.02
Si 0.02 0.02
Mn 0.05 0.05
P . 0.005
S . 0.005
N . 0.001
a
Cr 0.03 0.03
b
V 0.02 0.02
a. This is suitable only for HR310B,HR320,HR325, HT370B and HT370C.
b. This is suitable only when V content in liquid steel is greater than or equal to 0.04%.
Note: Tolerance beyond limits of specified chemical composition.
7.2.3 For all grades other than HT370C and HT400, the hydrogen contents of the liquid steel
-4 -4
shall not exceed 2.5×10 %, or the hydrogen contents of solid rails shall not exceed 2.0×10 %.
For the grades of HT370C and HT400, the hydrogen contents of the liquid steel or solid rails
-4
shall not exceed 1.7×10 %.
If the hydrogen contents of the first samples of a first heat or the heat sample of a second or
further heat do not comply with these requirements then the blooms made before those
samples are taken shall be slowly cooled or isothermally treated. This applies also to all blooms
made before the hydrogen content eventually complies with these requirements; in these cases,
all heats shall be tested in the rail form. In case of dispute, the hydrogen content shall be tested
in the rail form.
If any test result after corrective treatment fails to meet these requirements the heat shall be
rejected.
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7.2.4 Total oxygen content of liquid steel or product rail shall not exceed 20×10 %.
For orders greater than 5 000 tonnes at least 95 % of heats shall have a total oxygen content of
-4
less than 20×10 %. No more than 5 % of heats shall have a total oxygen content of up to
-4 -4
30×10 %. Heats with a total oxygen content greater than 30×10 % shall be rejected.
-4
For orders less than 5 000 tonnes, only one sample with total oxygen greater than 20×10 %,
-4 -4
but less than 30×10 %, is allowed. Heats with total oxygen greater than 30×10 % shall be
-4
rejected. Any heats with total oxygen above 20×10 % shall require that all subsequent heats
-4
be tested until values below 20×10 % are achieved.
7.3 Mechanical properties
The tensile strength, elongation and surface hardness of hot-rolled and heat-treated rail shall
meet the requirements as shown in Tables 8 and 9. The surface hardness shall not vary by
more than 30 HBW on any individual rail.
The internal hardness of heat-treated rails shall meet the requirements as shown in Table 10.
16 © ISO 2002 – All rights reserved

ISO/DIS 5003
Table 8 Tensile strength, elongation and surface hardness of hot-rolled(HR) rails
Elongation
Tensile strength Surface hardness
Steel grade
Rm(MPa) A(％) (HBW)
HR200 ≥680 ≥14 200-240
HR220 ≥770 ≥12 220-260
HR235 ≥800 ≥10 235-275
HR260A,HR260B ≥880 ≥10 260-300
HR280 ≥980 ≥10 280-320
HR310A,HR310B ≥980 ≥9 310-350
HR320 ≥1080 ≥9 320-360
HR325 ≥1080 ≥8 325-365
Table 9 Tensile strength, elongation and surface hardness of heat-treated(HT) rails
Tensile
Elongation Surface hardness
Steel grade strength
A(%) (HBW)
Rm(MPa)
HT320 ≥1080 ≥10 320-375
a
HT330 ≥1130 ≥10 330-390
b
HT340 ≥1175 ≥10 340-400
a
HT350A,HT350B ≥1175 ≥9 350-390
c
HT370A,HT370B ≥1175 ≥9 370-410
c
HT370C ≥1280 ≥9 370-410
d
HT400 ≥1280 ≥8 400-440
a. If the hardness exceeds 390 HBW, the rail is acceptable provided the microstructure is confirmed to
be pearlitic, and the hardness does
...