Common Pipe Specification Table

Nominal Diameter (DN) Outer Diameter of Steel Pipe Seamless Steel Pipe Wall Thickness (mm)
Series A Series B
10 Φ17.2 mm Φ14 mm
15 Φ21.3 mm Φ18 mm
20 Φ26.9 mm Φ25 mm
25 Φ33.7 mm Φ32 mm
32 Φ42.4 mm Φ38 mm
40 Φ48.3 mm Φ45 mm
50 Φ60.3 mm Φ57 mm
65 Φ76.1 mm Φ76 mm
80 Φ88.9 mm Φ89 mm
100 Φ114.3 mm Φ108 mm
125 Φ139.7 mm Φ133 mm
150 Φ168.3 mm Φ159 mm
200 Φ219.1 mm Φ219 mm
250 Φ273 mm Φ273 mm
300 Φ323.9 mm Φ325 mm
350 Φ355.6 mm Φ377 mm
400 Φ406.4 mm Φ426 mm
450 Φ457 mm Φ480 mm
500 Φ508 mm Φ530 mm
600 Φ610 mm Φ630 mm

Notes:

  • For pipes with pressure ratings PN40 and below, the material is Grade 20 steel, according to standard GB/T 8163.
  • For pipes with pressure ratings PN40 and above, the material is Grade 20 steel, according to standard GB 6479.

Explanation:

  • Nominal Diameter (DN): The standardized nominal diameter of the pipe (in millimeters).
  • Outer Diameter of Steel Pipe:
    • Series A and Series B refer to different standard series for pipe outer diameters as per national standards. The values are in millimeters (mm).
    • Φ denotes the diameter symbol.
  • Seamless Steel Pipe Wall Thickness (mm):
    • The columns labeled PN16, PN25, PN40, PN63, and PN110 (Class 600) indicate the nominal pressure ratings (in bars or nominal pressure units) according to which the wall thickness is specified.
    • The numbers under each pressure rating represent the required wall thickness (in millimeters) for seamless steel pipes at that nominal diameter and pressure rating.
    • PN stands for “Pressure Nominal”, indicating the nominal pressure class the pipe is designed to withstand.

Additional Information:

  • “-” (Dash): Indicates that the specification is not available or not standardized for that particular size and pressure rating.
  • Material Grades:
    • Grade 20 Steel: A commonly used carbon steel for pipes, suitable for a range of applications.
    • Standards Reference:
      • GB/T 8163: Standard for seamless steel pipes for fluid transportation.
      • GB 6479: Standard for high-pressure seamless steel pipes for chemical fertilizer equipment.