Special steel grades for gas cylinders and gas vessels

Usage

These steel grades are characterized by a minimum yield strength of 245 - 355 MPa and by good weldability. The user of these steel grades must make sure that his calculation, design and processing methods are appropriate for the material. The steel grades of this series are used for manufacturing gas cylinders by welding cold-formed parts together and normalizing the finished cylinder.

Standards

Europe Material no. DE FR IT GB JP FK1)
EN 10120 DIN 17155 2) NFA 36-211 UNI 7355 BS 5045 JIS G 3116
P245NB 1.0111 H I  BS 1 Fe E 24 KR Type A SG 255 A
P265NB 1.0423 H II BS 2 Fe E 27 KR Type B SG 295 A
P310NB 1.0437 17 Mn 4 BS 3 Fe E 31 KR Type C SG 325 B
P355NB 1.0557 19 Mn 6 BS 4 Fe E 35 KR Type E SG 365 B
  1. FK = Tensile strength class
  2. invalid standard

Chemical composition in percent by weight [%] (Heat analysis)

Grade C Si Mn P S N2) Altotal1) Ti Nb
max.  max. min. max. max. max. min. max. max.
P245NB 0.16 0.25 0.30 0.025 0.015 0.009 0.020 0.03 0.050
P265NB 0.19 0.25 0.40 0.025 0.015 0.009 0.020 0.03 0.050
P310NB 0.20 0.50 0.70 0.025 0.015 0.009 0.020 0.03 0.050
P355NB 0.20 0.50 0.70 0.025 0.015 0.009 0.020 0.03 0.050
  1. The aluminum content may in part be replaced by ≤ 0.050 % Nb and /or ≤ 0.03 % Ti.
  2. With a ratio of Altotal / N ≥ 2.2 or if Nb or Ti are added, the nitrogen content may be ≤ 0.012 %.

Mechanical properties1)

Grade Min. yield strength Tensile strength Min. total elongation2) [%]
[MPa] [MPa] L0= 80 mm  L0 = 5,65 √S0
e < 3 3 ≤ e ≤ 53)
P245NB 245 360 - 450 26 34
P265NB 265 410 - 500 24 32
P310NB 310 460 - 550 21 28
P355NB 355 510 - 620 19 24
  1. Transverse samples
  2. e = Nominal thickness in mm
  3. Mechanical values for greater thicknesses on request.

Welding

The steel grades of the P245NB - P355NB series may be welded using the usual welding techniques.

Condition of delivery, scope of testing and certificate

The provisions of EN 10120 shall apply for delivery and inspection.

Certificates according to DIN EN 10204 can be supplied as follows: IT, DUN, FAX, e-mail, paper.