HG/T 20631-2009 in English

1. Scope
This standard specifies the type, dimension, technical requirements and marking of spiral-wound gasket for use with steel pipe flanges (Class designated).
This standard is applicable to the spiral wound gaskets for use with steel pipe flanges whose nominal pressures are from C1assl50 (PN20)-C1ass600 (PN110) which are specified in HG/T 20615 and HG/T 20623.
2. Normative references
The following provisions contained in the following standards are turned into the provisions of this national standard by being referred in this national standard. For date reference, the subsequent amendments to (excluding amending error in the text) or revisions of, any of these publications do not apply. And parties to agreements based on this standard are encouraged to investigate the possibility of applying the most recent editions of the standards indicated below. For undated references, its latest edition referred to applies.
GB/T 912 "Hot-rolled Quality Carbon Structural Steel Sheets and Strips"
GB/T 3280 "Cold Rolled Stainless Steel Plate Sheet and Strip"
GB/T 4237 "Hot Rolled Stainless Steel Plate Sheet and Strip"
GB/T11253 "Cold-rolled Quality Carbon Structural Steel Sheets and Strips"
HG/T 20615 "Steel Pipe Flange (Class Designated)"
HG/T 20623 "Major Diameter Steel Pipe Flange (Class Designated)"
HG/T 20635 "Specification for Selection of Steel Pipe Flange, Gaskets and Bolting (Class designated)"
JB/T 7758.2 "Specifications of Flexible Graphite Sheets"
JC/T 69 "Compressed Asbestos Sheet"
QB/T 3628 "PTFE Raw Material Strip for use with Screw Thread Sealing"
3. General provisions
3.0.1 The type, code name, sectional form and proper type of flange sealing surface of the gasket shall meet the requirements of Table 3.0.1.

1. Scope
2. Normative references
3. General provisions
4. Dimension
5. Technical requirements
6. Inspection
7. Marking and labeling
7.1 Marking and illustration
7.2 Labeling
Appendix A (Informative) the Applied Minimum Pipe Wall Thickness of the Inside Diameter of Internal Ring for this Standard