Standard of the First Machinery Industry Department of the People's Republic of China Welded Cross-type Pipe Joints JB973-77 Replaces JB973-67 This standard applies to cross-type pipe joints in oil-based pipeline systems, with a nominal pressure of 320kgf/cm2 and a working temperature of -25 to 80℃. Marking example: Outer diameter of pipe D. 18mm four-way pipe joint: Pipe joint 18JB973-77 Issued by the First Machinery Industry Ministry of the People's Republic of China First Machinery Industry Ministry Standardization Institute Implementation on May 1, 1977 Jinan Foundry and Forging Machinery Research Institute, etc. Total 2 pages Page 2 Pipe outer diameter Nominal throughwww.bzxz.net Wrench size JB973-77 Standard number Technical conditions are in accordance with the provisions of JB1003--77. 1 TB2099·77 JB981-77 M12×1.25 M36×2 M42×2 M52×2 M60×2 The material of the seamless steel pipe is 15, 20 steel, and the precision is ordinary grade. 12 GB1235-76 Rubber I-4 JB991-77 Joint body Tip: This standard content only shows part of the intercepted content of the complete standard. If you need the complete standard, please go to the top to download the complete standard document for free.