Alloy Steel Pipe Material : ASTM A-335


This is a seamless ferritic alloy-steel pipe intended for elevated temperature service, more than 415 deg.C and upto 600 deg.C.

Pipe ordered to this specification shall be suitable for bending, flanging (vanstoning), and similar forming operations, and for fusion welding. These are seamless pipe only.

Available grades are : P1,P2,P5,P5B, P5C,P9,P11,P12,P15,P21,P22,P23,P91,P122,P911

They have higher chromium and molybdenum content than A106.

Grades P1, P11, P12 and P22 Used for Elevated Temperatures, above 427 deg. C upto 630 deg. C.

  1. P11 : Max 595 deg. C.
  2. P21 and P22 : Max 650 deg. C .
  3. P1 : 415 to 470 deg. C.
  4. P11 and P12 : 470 to 540 dg. C (P11 has higher chromial content hence more corrosion resistance than P12. Normally they are used interchangeably based on availability)
  5. P22 : 540 to 600 deg. C
  6. A312 TP 304H, 316H, 312 and 347H used above 600 deg. upto 815 deg. C