About EN 10028:3 Pressure Vessel Steel Plate
Plates to EN 10028:3 are widely specified in the manufacturing of pressure vessels throughout Europe. The standard is regularly seen in other parts of the world where equipment has been originally designed by a European company. For these reasons, and in terms of enquiries received by Brown McFarlane Group companies, it is probably the most popular pressure specification after the American standard ASME / ASTM SA/A516.
The specification EN 10028:3 covers a range of weldable fine grain steels supplied in the normalised condition and intended for pressure purposes. It has three steel grades (P275, P355, and P460) which indicate each grade’s minimum yield strength (in MPa) for plates 16 mm thick and below. These are further subdivided on the basis of impact testing (transverse) temperature: N and NH indicate impact testing at -20 deg C or above, NL1 at -40 deg C or above, and NL2 at -50 deg C or above.
The designation EN 10028:3 P355NL1 shows that this is steel for pressure purposes (P) with minimum yield strength of 355 MPa (355) which is impact tested in the transverse direction at -40 deg C (NL1). EN 10028:3 P355NL2 follows the same pattern but is impact tested at -50 deg C.
• What are the Differences between P355NL1 and P355NL2?
The differences between P355NL1 and P355NL2 can be seen in the tables below but are summarised as follows:
P355NL2 has a more tightly controlled Phosphorus and Sulphur content
P355NL2 has higher required impact values at all specified temperatures and in both longitudinal and transverse directions. It also specifies requirements for transverse impact testing at -50 deg C
- Dished ends
- Heat exchangers
- Pressure vessels
- Storage tanks
- Flanges & fittings
(cast analysis, % by mass, maximum permitted unless indicated otherwise)
|P355NL1||0.18||0.50||1.10 – 1.70||0.025||0.008||0.020 min||0.012||0.3||0.3||0.08||0.05||0.50||0.03||0.10||0.12|
|P355NL2||0.18||0.50||1.10 – 1.70||0.020||0.005||0.020 min||0.012||0.30||0.30||0.08||0.05||0.50||0.03||0.10||0.12|
|Product thickness||Yield strength (min) MPA||Tensile strength MPA||Elongation A%|
|up to 16mm||355||490 – 630||22 min|
|16mm to 40mm||345||490 – 630||22 min|
|over 40mm to 60mm||335||490 – 630||22 min|
|over 60mm to 100mm||315||470 – 610||21 min|
|over 100mm to 150m||305||460 – 600||22 min|
|over 150mm to 250mm||295||450 – 590||22 min|
|P355NL1||Tranverse||–||27 J min||35 J min||50 J min||60 J min|
|P355NL2||Transverse||27 J min||30 J min||40 J min||60 J min||70 J min|
|P355NL1||Lonigitudinal||30 J min||40 J min||50 J min||70 J min||80 J min|
|P355NL2||Lonigitudinal||42 J min||45 J min||55 J min||75 J min||85 J min|