BS 1501 224 490B LT50

Pressure vessel plate manufactured and certified to BS 1501 224 490B LT50 forms a significant part of Brown McFarlane’s stock inventory.

BS 1501 - background

BS 1501:1980 Part 1, despite being officially withdrawn on 15th February 1993, remains a steel specification that is in regular use and we see daily sales and enquiries for grades that form a part of this standard particularly from our customers in the U.K.

BS 1501 224 specifies requirements for fully killed aluminium treated carbon manganese steel plates up to 150 mm thick in four grades which relate to minimum tensile strength. The plates may also be supplied having specified elevated temperature properties and low temperature impact properties. Plates are supplied in the normalised condition unless an alternative is agreed between supplier and purchaser.

BS 1501 224 490B LT50 - the specification

The grade BS 1501 224 490B LT50 shows that the steel will have a minimum tensile strength of 490 N/mm2 (490), has elevated temperature properties reported (B), and has low temperature impact properties specified at -50 deg C (LT50).

As well as BS 1501 224 490B LT50, we are also stockists of plates manufactured and certified to:

BS 1501 223 490B LT30                    BS 1501 225 490B LT50

Chemical Requirements

Chemical composition (ladle analysis, %) of steel 224

C Si  Mn  S 
0.22 max 0.10 - 0.40  0.90 - 1.60  0.030 max 0.030 max
Al (metallic) Cr* Cu* Mo*  Ni 
0.015 min 0.25 max 0.30 max 0.10 max 0.75 max
*Cr+Cu+Mo = 0.50% max

Tensile Requirements

Plate Thickness Tensile Rm Yield Re Elong. A
over 3 mm to 16 mm  490 - 610 N/mm2  325 N/mm2 min 21% min 
over 16 mm to 40 mm  490 - 610 N/mm2  315 N/mm2 min  21% min 
over 40 mm to 63 mm  490 - 610 N/mm2  305 N/mm2 min 20% min 
over 63 mm to 100 mm  490 - 610 N/mm2  * 19% min 
over 100 mm to 150 mm  490 - 610 N/mm2  19% min 

*The value of yield strength for plates over 63 mm thick shall be the values specified for plates of thickness between 40 mm and 63 mm reduced by 1% for each 5 mm or part thereof increase in thickness over 63 mm.

Charpy V-notch impact values

Impact test values, average of three at tempereature specified below

RT 0o -20o -30o -40o -50o
61 J min 55 J min  47 J min  41 J min  31 J min  27 J min 

Values apply to plates up to and including 80 mm thick

Comparable Steel Specifications

Although it is not uncommon to see this on steel company web sites, any suggestion that one steel specification and grade is an equivalent to another should be treated with caution especially because of differences in the methodology and techniques used for testing. However BS 1501 224 490B LT50 is broadly similar to the following steel specifications:

ASME SA516 Gr. 70          EN 10028:3 P355NL2

Plates certified to these standards are held in stock by Brown McFarlane.

For more information please contact our sales teams. Click here to go to the page giving contact details.


Plate Cutting

Plate Processing

  • Weld preparations
  • Grinding
  • Drilling and tapping
  • Pressing
  • Machining
  • Shotblasting and painting
  • Rolling
  • Rolled shells
  • Dished ends
  • Clad plates


Boiler and Pressure Vessel Steel Plate pdf

The largest stock in the UK with plate up to 4m wide and 20m long from 3mm to 200mm thick. 

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