This standard specifies the type, size, technical requirements and marks of neck socket welded steel pipe flanges marked with PN and Class with nominal pressure. This standard applies to neck socket welded steel pipe flanges with nominal pressures of PN10~PN100 and Class150~Class1500.
GB/T 9117-2010 Referenced Document
GB/T 9112 Types and parameters for steel pipe flanges
GB/T 9124 Specifications for steel pipe flanges*, 2011-10-01 Update