BT type CNC tool holder is mainly a Japanese standard, and it is also a commonly used standard. 7:24 taper universal tool holder Taper 7:24 universal tool holder usually has five standards and specifications, namely NT (traditional type), DIN69871 (German standard), IS07388/1 (international standard), MASBT (Japanese standard) ) and ANSI/ASME (American Standard).

The German standard for the NT type tool holder is DIN2080. The tool holder is tightened by a pull rod on a traditional machine tool. It is also called ST in China; the other four tool holders are all used on the machining center. tension. MASBT type (abbreviated as BT) BT type is a Japanese standard, and its installation dimensions are completely different from DIN69871, IS07388/1 and ANSI, and cannot be replaced.

The symmetrical structure of the BT-type tool holder makes it more stable at high speed than the other three tool holders. The shank and the shank are selected from Tihao. The shank has 30, 35, 40, 45, 50 and 60 gauges, which indicate the diameter of the taper shank somewhere (the specific position is different in different standards). The size of the cone is usually selected by the machine tool manufacturer according to the effective power of the machine tool or the overall length of the tool used, and is also related to the country of origin (DIN standard in Europe, ANSI standard in the United States, and JIS standard in Japan). The commonly used tool holder specifications are 30, 40, and 50, of which 40 is the most widely used.