The criterions of seal design are presented that can keep the joint leak-tight as well as not damaging the seal surface.
给出了设计石油套管特殊螺纹接头时,既能保证其密封性,又不至于发生粘结损坏的条件。
2
The standard covers dimensions and gaging of plastic tapered National Pipe Threads (NPT) for leak-tight joints, and it is now referenced in all ASTM Standards for plastic piping products.