Application knowledge of tool holder in CNC tool

Application knowledge of tool holder in CNC tool

The spindle taper hole of machining center is usually divided into two categories: the general system with taper of 7:24 And the HSK vacuum system with taper of 1:10.

1. The general tool holders with taper of 7:24

There are usually five standards and specifications for general tool holders with a taper of 7:24, namely NT (traditional), DIN69871 (German standard), IS07388/1 (International Standard), MAS BT (Japanese standard) and ANSI/ASME (American Standard).

The German standard of NT type tool holder is DIN 2080, which tightens the tool holder through the pull rod on the traditional machine tool, also known as st in China; The other four kinds of tool holders are tightened on the machining center through the pull stud at the tail of the tool holder.

At present, DIN 69871 (i.e. JT) and MAS BT tool holders are the most used in China.

The tool holder of DIN69871 type can be installed on the machine tool of DIN69871 type and ANSI/ASME spindle taper hole, and the tool holder of IS07388/1 type can be installed on the machine tool of DIN69871 type, IS07388/1 type and ANSI/ASME spindle taper hole. Therefore, in terms of universality, the tool handle of IS07388/1 type is the best.

(1) DIN2080 type (NT or ST for short)

DIN2080 is a German standard, i.e. international standard ISO2583. It is what we usually call NT type tool handle. The tool can not be loaded by the manipulator of the machine tool, but by hand.

(2) Din 69871 (JT, DIN, dat or DV for short)

There are two types of DIN69871, namely DIN69871 A/AD and DIN69871B, the former is central internal cooling, the latter is flange internal cooling, and other dimensions are the same.

(3) ISO7388/1 (IV or it for short)

The mounting dimension of the tool holder is no different from that of DIN69871. However, since the D4 value of ISO7388/1 tool holder is less than that of DIN69871 tool holder, it is no problem to install ISO7388/1 tool holder on the machine tool with DIN69871 taper hole, but there may be interference when installing DIN 69871 tool holder on ISO7388/1 machine tool.

(4) MAS BT type (BT for short)

BT type is a Japanese standard. The installation dimensions are completely different from DIN69871, IS07388/1 and ANSI, and cannot be replaced. The symmetrical structure of BT tool handle makes it better than the other three tool handles in high-speed stability.

(5) ANSI B5. Type 50 (CAT for short)

ANSI B5. Type 50 is an American Standard, and the installation dimension is similar to DIN69871 and IS07388/1, but ANSI B5 is adopted due to the lack of a wedge notch Type 50 tool handles cannot be installed on din69871 and IS07388/1 machine tools, but DIN69871 and IS07388/1 tool handles can be installed on ANSI B5 Type 50 machine tool.

2. 1:10 HSK vacuum tool holder

The German standard for HSK vacuum tool holder is DIN69873. There are six standards and specifications, namely HSK-A, HSK-B, HSK-C, HSK-D, HSK-E and HSK-F. There are three commonly used: HSK-A (automatic tool change with internal cooling), HSK-C (manual tool change with internal cooling) and HSK-E (automatic tool change with internal cooling, high-speed type).

7: 24 general tool holder is connected by the contact and positioning of the 7:24 conical surface of the tool handle and the 7:24 conical surface of the spindle hole of the machine tool. It has limitations in three aspects: high-speed machining, connection rigidity and coincidence accuracy. HSK vacuum tool handle not only contacts the 1:10 conical surface of the tool handle with the 1:10 conical surface of the spindle hole of the machine tool, but also makes the flange surface of the tool handle in close contact with the spindle surface. This double-sided contact system is better than 7:24 in high-speed machining, connection rigidity and coincidence accuracy.