美利体育登录入口官网:CSN EN 22 857-1993
公差为4H-8H和4G-6G的粗牙与细牙ISO公制螺纹磨牙螺纹丝锥.螺纹部分的制造公差(ISO 2857-1973 包括修订1:1984和修订2:1986).
Ground thread taps for ISO metric threads of tolerances 4H to 8H and 4G to 6G coarse and fine pitches; Manufacturing tolerances on the threaded portion (ISO 2857:1973 incl. Amd 1: 1984 and Amd 2: 1986)