This standard specifies the type, size, technical requirements and marks of the neck threaded steel pipe flanges marked with PN and Class for nominal pressure. This standard is applicable to neck threaded steel pipe flanges with nominal pressure PN6~PN100 and Class150~Class2500.
GB/T 9114-2010 Referenced Document
GB/T 12716 Pipe threads with the thread angle of 60 degrees where pressure-tight joints are made on threads *, 2011-12-30 Update
GB/T 7306.1 Pipe threads with 55 degree thread angle where pressure-tight joints are made on the threads Part 1:Parallel internal and taper external threads
GB/T 7306.2 Pipe threads with 55 degree thread angle where pressure-tight joints are made on the threads Part 2:Taper internal and external threads
GB/T 9124 Specifications for steel pipe flanges*, 2011-10-01 Update