What is GB9123.2-2000 concave and convex steel pipe flange cover

1 Scope This standard specifies the types and dimensions of concave and convex steel pipe flange covers with nominal pressures PN of 1.6, 2.5, 4.0, 6.3, 10.0, 16.0MPa and nominal pressures PN of 5.0, 11.0, 15.0, 26.0MPa. This standard is applicable to steel pipe flange covers with concave and convex surfaces with nominal pressures PN1.6~PN26.0MPa. ​

2 Referenced standards The provisions contained in the following standards constitute provisions of this standard through reference in this standard. At the time of publication, the editions indicated were valid. All standards are subject to revision and parties using this standard should explore the possibility of using the latest version of the standard listed below. GB/T 9112—2000 Steel Pipe Flange Types and Parameters GB/T 9124—2000 Steel Pipe Flange

Technical conditions

3 Types and dimensions of flange covers 3.1 The types and dimensions of PN1.6, PN2.5, PN4.0, PN6.3, PN10.0 and PN16.0MPa concave and convex surface steel pipe flange covers should comply with the requirements of Figure 1. It should comply with the provisions of Table 1 to Table 6.

3.2 The type of PN5.0, PN11.0, PN15.0 and PN26.0MPa concave and convex steel pipe flange covers shall comply with the requirements in Figure 2, and the dimensions shall comply with the requirements in Tables 7 to 10.

4 Technical requirements for flange covers

4.1 The technical requirements of the flange cover should comply with the provisions of GB/T 9124.

4.2 The maximum non-impact working pressure of the flange cover at different temperatures should comply with the provisions of GB/T 9124-2000 Appendix A (standard appendix).

5 marks

5.1 The flange cover should be marked according to the nominal diameter, nominal pressure, sealing surface type code and standard number.

5.2 The type code of the flange cover sealing surface should comply with the regulations of GB/T 9112.

5.3 Marking example: nominal diameter 80mm, nominal pressure

5.0MPa (50bar) convex stainless steel pipe flange cover: Flange cover DN80-PN50 M GB/T 9123.2-2000 Concave steel pipe with nominal diameter 80mm and nominal pressure 2.5MPa (25bar)

Flange cover: Flange cover DN80-PN25 F GB/T 9123.2—2000