BT type CNC tool holder is mainly a Japanese standard and is now a commonly used standard. Universal tool holders with a taper of 7:24 generally have 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 of the NT type tool holder is DIN2080. The tool holder is tightened through a pull rod on a traditional machine tool. It is also called ST in China. The other four tool holders are tightened on the machining center through pull nails at the end of the tool holder. tension. MAS BT type (abbreviated as BT) BT type is a Japanese standard. The installation dimensions are completely different from DIN 69871, IS0 7388/1 and ANSI and cannot be interchanged.
The symmetrical structure of the BT type tool holder makes it have better high-speed stability than the other three types of tool holders. The tool shank has specifications of 30, 35, 40, 45, 50 and 60, which indicates the size of the diameter somewhere on the taper shank (the specific location is different in different standards). The specifications of the cone are usually selected by the machine tool manufacturer based on the effective power of the machine tool or the overall length of the tool used, and are also related to the country of production (DIN standard in Europe, ANSI standard in the United States, and JIS standard in Japan). Commonly used tool holder specifications are 30, 40, and 50, of which 40 is the most widely used. R collet, commonly known as spring chuck, is a drill chuck installed on the machine tool spindle. Its function is to lock the connection between the tool and the spindle.
