Data sheet: A6.3
Plate to BS 1501: Part 1 1980:490 MPa Grades
Higher strength carbon manganese pressure vessel steel plate
General description
A wide range of steels may be used for pressure vessels designed and built to the British Code BS 5500.
Some of these steels are specified in BS 1501 Parts 1, 2 and 3. Part 2 refers to alloy steels and Part 3 to
stainless steel.
This data sheet addresses two higher strength steels of Part 1, ‘Specification for carbon and carbon
manganese steels’ readily available from Mittal Steel South Africa namely:


BS 1501 - 224 Grade 490: A fully killed, aluminium treated carbon manganese steel.
BS 1501 - 225 Grade 490: A fully killed, niobium and aluminium treated carbon manganese steel.
Both these grades are fully killed, fine grained steels and are calcium treated to ensure very low levels of
sulphur content and inclusions. Furthermore, by inclusion shape control, excellent through-thickness and
notch toughness properties are achieved and the risk of lamellar tearing in heavy weldments is minimised.
Both grades are available in thicknesses up to 63mm.
It should be noted that BS 1501 has been replaced by BS EN 10028. Mittal Steel South Africa will,
however, endeavour to supply steel in accordance with BS 1501 until market forces make the use of this
specification redundant.
These steels are designated by the specification number, steel type number and a grade number which
represents the minimum tensile strength, for example BS 1501 - 224 Grade 490. The suffix A or B is added
to the grade number, A being used if tensile properties are required at room temperature and B when
characteristic elevated temperature properties need also be guaranteed. The further suffix LT is added if
impact tests are to be carried out at temperatures below 0oC, e.g. LT 30 for -30°C. A full designation
will, for example, be: BS 1501 - 224 Grade 490A LT 30.
These steels are all readily weldable by the usual metal arc welding processes. When welding thick
plates, reference should be made to BS 5135: 1984, ‘Specification for arc welding of carbon and carbon
manganese steels’ to establish possible preheat requirements, especially at low heat inputs. Values of
the carbon equivalent (CE) should be calculated from the values for chemical composition on the test
certificates for the plates concerned.
All plates will be supplied normalised, unless agreed to be supplied as rolled, in which case only the test
pieces will be normalised. Such plates are to be normalised by the fabricator.
Chemical composition
Table 1 shows the chemical composition as specified by BS 1501: Part 1: 1980. The limits are set rather
wide to give the steel producer maximum scope to apply his manufacturing techniques. In order to assist
For further information, contact:
Mittal Steel South Africa Limited, PO Box 2, Vanderbijlpark 1900. Toll free number 0800 005043, Fax (016) 889-0070
e-mail address: datasheets@mittalsa.com
Care has been taken to ensure that the information in this data sheet is accurate. Mittal Steel South Africa Limited does not, however,
assume responsibility for any inaccuracies or misinterpretations of this data. We are continuously engaged in product development and
revised data sheets will be issued from time to time. Please ensure that you have the most recent issue. Effective date: October 2005
Page 1 of 4
File reference: A6.3
Price List reference 110
customers in determining fabrication parameters, the typical analyses of the steels as made by Mittal
Steel South Africa are given in Table 2. It must be stressed that these values are given as an indication
only and are in no way binding on Mittal Steel South Africa as manufacturer. Only the specification is
binding. It should also be noted that, because thicker plates cool at a slower rate during and after rolling
or normalising, they will emerge at lower strength levels if the chemical composition is not enriched to
counteract this effect (even though the specification does allow for some strength reduction with
thickness).
Table 1. Chemical composition (ladle analysis, percent) as specified in BS 1501: Part 1: 1980,
Tables 23, 26 and 29
Type
C
max
Mn
Si
P
max
S
max
Altot
min
Nb
Cr1
max
Cu1)2
max
Mo1
max
Ni3
max
224
Grade
490
0,22
0,90 1,60
0,10 0,40
0,030
0,030
0,018
-
0,25
0,30
0,10
0,75
225
Grade
490
0,20
0,90 1,60
0,10 0,50
0,030
0,030
0,018
0,010 0,060
0,25
0,30
0,10
0,75
Notes:
1. (Chromium + copper + molybdenum) = 0,50% max.
2. Copper + 10.Tin  0,40%. Tin is reported.
3. The purchaser may specify a maximum nickel content of 0,30%. In this case the total chromium +
copper + molybdenum + nickel = 0,70% max
Table 2: Typical chemical composition (ladle analysis, percent) as produced by Mittal Steel South Africa
Type
Thickness t
(mm)
C
Mn
Si
Al
Nb
S
P
224 Grade 490
6t8
0,16
1,35
0,28
0,04
-
0,008
0,015
8 < t  63
0,19
1,45
0,32
0,04
-
0,008
0,015
6 < t < 63
0,16
1,45
0,42
0,04
0,025
0,008
0,015
225 Grade 490
Mechanical properties
1. Room temperature tensile properties
Table 3: Mechanical properties at room temperature as specified in BS 1501: Part 1: 1980 tables 24, 27
and 30
Type
Nominal plate
Tensile strength
Minimum yield
Minimum
thickness t
(MPa)
strength
elongation1
(mm)
(MPa)
%
224 Grade 490
4,5 < t  16
16 < t  40
40 < t  63
490-610
490-610
490-610
325
315
305
21
21
20
225 Grade 490
4,5 < t  16
16 < t  40
40 < t  63
490-610
490-610
490-610
355
345
340
21
21
20
Note:
1. Gauge length = 5,65 S o . Refer to paragraph 20.1 in the specification.
For further information, contact:
Mittal Steel South Africa Limited, PO Box 2, Vanderbijlpark 1900. Toll free number 0800 005043, Fax (016) 889-0070
e-mail address: datasheets@mittalsa.com
Care has been taken to ensure that the information in this data sheet is accurate. Mittal Steel South Africa Limited does not, however,
assume responsibility for any inaccuracies or misinterpretations of this data. We are continuously engaged in product development and
revised data sheets will be issued from time to time. Please ensure that you have the most recent issue. Effective date: October 2005
Page 2 of 4
File reference: A6.3
Price List reference 110
2. Impact toughness
Table 4. Charpy v-notch impact energy as specified in BS 1501: Part 2: 1980 Tables 25, 28 and 31
Type
Impact energy (J) at temperature (°C)
RT1
0
-20
-30
-40
-50
224 Grade 4902
61
55
47
41
31
27
225 Grade 4902
-
-
61
47
-
27
Notes:
1. Room temperature
2. Values for plate up to and including 63mm thick
3. Elevated temperature yield strength or proof stress
In Appendix E of BS 1501: Part 1: 1980 (for steel type 225) and Appendix F (for type 224) the specification
shows the yield strength or proof stress at elevated temperatures for the respective types. These values
may be used for design purposes, but if a user requires verification of the strength at any particular
temperature, a tensile test at that temperature must be stipulated on the order.
Table 5: Minimum yield strength or 0,2% proof stress at elevated temperatures
Type
Nominal
Minimum yield strength or proof stress (MPa)
plate
at temperature
thickness t
(mm)
150°C
200°C
250°C
300°C
350°C
400°C
224 Gr 490
225 Gr 490
6 < t  16
16 < t  40
40 < t  63
6 < t  16
16 < t  40
40 < t  63
450°C
265
260
256
240
237
234
213
213
213
192
192
192
182
182
182
173
173
173
-
284
284
284
258
258
258
240
240
240
220
220
220
206
206
206
195
195
195
187
187
187
Dimensions
The available dimensions of plate supplied both in the as rolled and normalised conditions are shown on
the data sheet: Plate Mill Products: Available Dimensions (Domestic Market) (file reference A1.3).
Dimensional tolerances
Plates to BS 1501: Part 1 are supplied to the dimensional tolerances specified in BS EN 10 029, unless
otherwise agreed at the time of the enquiry and order.
Ultrasonic tests
All plates thicker than 20mm are ultrasonically tested to BS 5996: B1 as an integral part of Mittal Steel
South Africa’s quality assurance system. Ultrasonic testing to stricter criteria is available on enquiry.
Surface inspection
Plates are inspected and defects repaired in accordance with specification BS EN10 1063: Part 2, Class B,
Subclass 2, unless otherwise agreed at the time of the enquiry and order.
For further information, contact:
Mittal Steel South Africa Limited, PO Box 2, Vanderbijlpark 1900. Toll free number 0800 005043, Fax (016) 889-0070
e-mail address: datasheets@mittalsa.com
Care has been taken to ensure that the information in this data sheet is accurate. Mittal Steel South Africa Limited does not, however,
assume responsibility for any inaccuracies or misinterpretations of this data. We are continuously engaged in product development and
revised data sheets will be issued from time to time. Please ensure that you have the most recent issue. Effective date: October 2005
Page 3 of 4
File reference: A6.3
Price List reference 110
Certification
All material described in this data sheet is supplied with test and analysis certificates.
Supply conditions
BS 1501 plate is supplied in terms of Price List 110 and Mittal Steel South Africa's General Conditions of
Sale.
For further information, contact:
Mittal Steel South Africa Limited, PO Box 2, Vanderbijlpark 1900. Toll free number 0800 005043, Fax (016) 889-0070
e-mail address: datasheets@mittalsa.com
Care has been taken to ensure that the information in this data sheet is accurate. Mittal Steel South Africa Limited does not, however,
assume responsibility for any inaccuracies or misinterpretations of this data. We are continuously engaged in product development and
revised data sheets will be issued from time to time. Please ensure that you have the most recent issue. Effective date: October 2005
Page 4 of 4
File reference: A6.3
Price List reference 110