DIN EN 22857-1990 ISO公制螺纹公差为4H到8H和4G至6G的粗牙与细牙的磨牙丝锥.螺纹部分的制造公差
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); german version EN 22857:1989
The standard specifies the manufacturing tolerances on the threaded portion of taps for producing the ISO metric threads of tolerances classes 4H to 8H and 4G to 6G, according to ISO 965-1 to 965-3.#,,#