Home / Standards / GB/T 7307-2001 GB/T 7307-2001 Active Pipe threads with 55 degree thread angle where pressure-tight joints are not made on the threads 55°非密封管螺纹 Standard Type GBT ICS 21.040.30 CCS J04 Status 现行 Issue Date 2001-02-26 Implementation 2001-09-01 Responsible Dept 国家标准委 Drafting Unit 国家标准委