NORMAL STRENGTH CARBON & CARBON MANGANESE PRESSURE VESSEL
STEEL PLATE
B.S.1501: 430 MPa Grades
DESCRIPTION
B.S.1501-161-430A/B is a British Standard Specified steel which has now been superseded by
the Euro Norm Specification EN 10028.
As reference is still being made to this material by prospective clients, we have included
details of B.S.1501-161-430A/B on this reference
for information purposes.
The steel is used in the fabrication of welded pressure vessels and boilers.
There are two types of BS1501-161-430 available which are as follows:
Type A:
Denotes specified min. room temperature tensile properties
Type B: As per Type A but with elevated temperature properties.
A wide range of steel plate specifications may be used for Pressure Vessels designed and
built to the British construction code PB 5500.
These steels are specified in BS 1501: Parts 1,2 and 3.
Part 1 refers to carbon and carbon manganese steels, Part 2 to alloy steels and Part 3 to
stainless Steel.
This data sheet deals with one steel in Part 1,’Specification for carbon and carbon
manganese steels’, namely:
BS 1501-161 grade 430, a fully killed carbon steel available in thicknesses up to and
including 100mm.
These steels are designated by the specification number, steel type number and a grade
number which represents the minimum
tensile strength e.g. BS 1501-161 grade 430.
In addition, the suffix A or B is added to the grade number, ‘A’ being used if tensile
properties are guaranteed at room temperature only
and ‘B’ being used when characteristic elevated temperature properties are guaranteed in
addition to the room temperature properties.
The suffix RT is applicable when impact tests are to be performed at room temperature.
The suffix LT is added if sub-zero impact tests are to be carried out, the temperature being
included, e.g. LT30 for impact testing at -30°C.
Hence a full designation will be as follows: BS 1501-161 grade 430B, LT30.
Steel Making
Steel is normally supplied from a basic oxygen furnace but could also be supplied from
electric arc furnaces using clean internal scrap and direct reduced iron.
All steel is desulphurised to maintain a high degree of cleanliness and is made fully killed
and fine-grained from continuously cast slabs.
Full shrouding techniques and automatic mould level control are applied to ensure superior
internal and surface quality.
Chemical composition
Table 1 shows the chemical composition as specified by BS 1501: Part 1: 1980.
Table 1. Chemical composition (ladle analysis, percent) as specified in BS 1501: Part 1: 1980
Type
161
Grade
430
C
max
0.25
Mn
Si
0,601,40
0,100,35
P
max
0,030
S
max
0,030
Al
min
-
Cr
max
0,25
Cu
max
0,30
Mo
max
0,10
Ni
max
0,30
N
max
0,012
CE
max
0,41
Heat treatment condition
Plates up to and including 40mm are supplied as rolled unless normalizing is
requested by the purchaser.
Where cold forming of plate thicknesses thinner than or equal to 40mm is intended,
normalizing is a prerequisite.
Plates over 40mm thick are supplied normalized unless supply in the as rolled
condition is required, in which case the test pieces
will be normalized.
Plates up to and including 40mm are supplied as rolled unless normalizing is
requested by the purchaser.
Where cold forming of plate thicknesses thinner than or equal to 40mm is intended,
normalizing is a prerequisite.
Plates over 40mm thick are supplied normalized unless supply in the as rolled
condition is required in which case the test pieces will be
normalized
Mechanical Properties
Room temperature tensile properties
Table 2. Mechanical properties at room temperature as specified in BS 1501: Part 1: 1980
Type
161 grade 430
Nominal
thickness t
(mm)
t ≤ 16
16 < t ≤ 40
40 < t ≤ 63
63 < t ≤ 80
Tensile
Strength
(MPa)
430 – 550
430 – 550
430 – 550
430 - 550
Minimum yield
Strength
(MPa)
250
240
230
220
Note:
1. Gauge length 5,65√S₀. Refer to paragraph 20.1 in the specification.
Minimum
Elongation
(%)
23
23
22
21
Impact resistance
Note:
1. The specification has no impact test requirements for steel type 161.
Elevated temperature yield strength or proof stress
In appendix D (for steel types 151 and 161) and appendix F (for steel type 224). The
specification shows the yield strength or proof stress values
of the respective grades at elevated temperature.
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 this temperature must be stipulated on the order. The high temperature yield strength
values for these steels are summarized in the
table below.
Table 3. Minimum yield strength or 0,2% proof stress at elevated temperature
Type
151
and
161
Nominal
Thickness t
(mm)
t ≤
16
16 < t ≤ 40
40 < t ≤ 63
63 < t ≤ 80
Minimum yield strength or proof stress (MPa) at temperature
150°C
200°C
250°C
300°C
350°C
400°C
222
210
200
186
215
202
192
181
192
181
178
172
161
161
161
161
153
153
153
153
148
148
148
148
Dimensions
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.
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.
Certification
All material described in this data sheet is supplied with test and analysis certificates.
Weldability
The normal strength pressure vessel steels to BS 1501 are all readily weldable by the usual
metal arc welding processes.
When welding plates thicker than 20mm, reference should be made to BS 5135: ‘Metal arc
welding of carbon and carbon manganese steels’,
to establish possible preheat requirements, especially at low heat inputs.
Values of the carbon equivalent used to generate welding procedures should be calculated
from the values for chemical composition on the
test certificates for the plates concerned, not from the tables on this data sheet.
Attention is drawn to paragraph 7.4.4 of the specification, regarding maximum carbon
equivalent requirements in the event that post weld
heat treatment is specified.
Note: This data sheet merely gives some important commonly used parameters.
It is strongly recommended that users of steel to BS 1501: Part 1: 1980 should study the
specification in full.