This standard specifies the nominal pressure and nominal dimension of steel pipe flanges and blank flanges and the outside diameter of steel pipe, flange types and codes, sealing face types and code as well as the application scope of various types of flanges.
This standard is applicable to the steel pipe flanges and blank flanges specified in GB/T 9113~9123.
2 Normative References
The following standards contain provisions which, through reference in this standard, constitute provisions of this standard. For dated reference, subsequent amendments to (excluding correction to), or revisions of, any of these publications do not apply. However, the parties to agreements based on this standard are encouraged to investigate the possibility of applying the most recent editions of the standards. For undated references, the latest edition of the normative document referred to applies
GB/T 9113 Integral Steel Pipe Flanges
GB/T 9114 Hubbed Screwed Steel Pipe Flanges
GB/T 9115 Steel Pipe Welding Neck Flanges
GB/T 9116 Hubbed Slip-on-welding Steel Pipe Flanges
GB/T 9117 Hubbed Socket Welding Steel Pipe Flanges
GB/T 9118 Loose Hubbed Steel Pipe Flanges with Welding Neck Collar
GB/T 9119 Slip-on-welding Steel Pipe Flanges
GB/T 9120 Loose Hubbed Steel Pipe Flanges with Weld-neck Collar and with Weld Ring Neck
GB/T 9121 Loose Plate Steel Pipe Flanges with Weld-on Collar
GB/T 9122 Loose Plate Steel Pipe Flanges with Lapped Pipe End and Pressed Collar with Long Neck
GB/T 9123 Steel Pipe Blank Flanges
3 Nominal Pressure
This standard specifies 12 nominal pressure classes of the PN-designated nominal pressure and 6 pressure classes of Class-designated nominal pressure. The nominal pressure designations of these two series are as follows:
PN series Class series
