NPTPTGZGBSPPBSPTNPTRPRCR各种英标美标螺纹的区别及标准
For personal use only in study and research; not for commercial use关於英制管螺纹1/4"bspp的具体意义如下:螺纹代号为G1/4,
NPTPTGZGBSPPBSPTNPTRPRCR各种英标美标螺纹的区别及标准