1. Scope
This national standard specifies pattern, dimension, and technical requirement and marking of PTFE envelope gasket for use with steel pipe flanges (PN designated).
This Standard is applicable to PTFE envelope gasket for use with steel pipe flange with raised face in nominal pressure of PN6~PN40 and in working temperature of less than or equal to 150℃ specified in HG/T 20592.
Note: the use of the asbestos-contained material shall comply with requirements of relevant laws and regulations. When the production and use are containing asbestos material gasket, protective measures shall be adopted, so as to ensure not endanger the person health.
2. Normative references
The following standards contain provisions which, through reference in this text, constitute provisions of this Standard. For dated reference, subsequent amendments (excluding content of corrigenda) to, or revisions of, any of these publications do not apply. However, Parties to agreements biased on this Code are encouraged to investigate the possibility of applying the most recent editions of the standards indicated below. For undated references, the latest edition of the normative document referred to applies.
"Compressed Asbestos Fibre Jointing" GB/T 3985
"Non-metallic PTFE Envelope Gaskets for Pipe Flanges" GB/T 13404
"Steel Pipe Flanges (PN designated)" HG/T 20592
1. Scope
2. Normative references
3. Gasket pattern and dimension
4. Technical requirement
5. Marking and packaging
