Characteristics and Application of BT and HSK Tool Holders

July 23, 2019

HSK handle is a high-speed handle, especially the E series keyless groove is the highest dynamic balance standard main handle SK series speed can not be too high, generally about 10,000 to the limit (limited and pull nail tension mode), but HSK due to the complexity of manufacturing, belongs to the type of over-positioned internal rising price is relatively high, and Kenna specially made for Mazak similar. HSK handles are mostly used in turning and milling centers. Look at the data for yourself.

SK series (7:24 taper)

A: BT series, Japanese standard
B: JT Series (DIN 69871) German Standard
C: CAT Series
DIN 2080 series,

There are five main categories of A, B, C, D and E for manual switching to HSK series.

At present, there are 7/24 and 1/10 taper shank shanks in the main market, of which 7/24 have CNC and general use, CNC has international standards, Germany, Japan, the United States. Common use is distinguished between metric system and British system.
In the Chinese market, the BT model is most used in Japan, and the German DIN69871 (SK or NC), 1/10 taper shank, because of its cost and manufacturing technology problems, few domestic enterprises have been able to do it, its model with HSK machine spindle requirements are relatively high, domestic manufacturers have not yet been widely used.
In the manufacturing company of tool handle, BBT of BIG company in Japan can replace hsk, because HSK is hollow handle and has some structural strength problems, but BBT is different. The positioning accuracy of tool handle has self-positioning (such as BT) and over-positioning (such as HSK and BIG). Static accuracy is good, the main difference is dynamic accuracy. It is said that HSK can still be used at high speed. Maintaining the tightness of contact with the spindle and having good dynamic accuracy, it is widely used in high speed machining.

BT and HSK are used to transfer torque through keys, and some shanks transfer torque through their own shapes (such as Capto interface). Generally, the shanks that transfer torque through their own shapes are known to be larger and more stable, especially at high speed.
Machining center spindle taper holes are usually divided into two categories, namely, the universal system with taper of 7:24 And the HSK vacuum system with taper of 1:10. The universal tool holder with taper of 7:24 usually has five standards and specifications, namely NT (traditional type), DIN 69871 (German standard), IS0 7388/1 (international standard), MAS BT (Japanese standard) and ANSI/ASME (American standard). The German standard of NT type tool holder is DIN 2080, which is to tighten the tool holder by pulling rod on traditional machine tools, also known as ST in China; the other four kinds of tool holders are tightened by pulling nails at the end of the tool holder on the processing center. At present, DIN 69871 (JT) and MASBT are the two most widely used tool holders in China. The tool holder of DIN 69871 can be installed on the machine tools of DIN 69871 and ANSI/ASME spindle taper holes. The tool holder of IS0 7388/1 can be installed on the machine tools of DIN 69871, IS0 7388/1 and ANSI/ASME spindle taper holes. So the tool holder of IS0 7388/1 is the best for generality.

There are three key parameters of the pull nail: theta angle, length L and thread G.

There are several cases about the angle of theta of knife handle pull nail as follows:
1. MAS BT (Japanese Standard) holder pull nail angle is 45 degrees, 60 degrees and 90 degrees, commonly used is 45 degrees and 60 degrees;
2. The angle of theta of DIN 69871 knife handle pull nail (usually called DIN 69872-40/50) is only 75 degrees.
3. The angle of theta of IS0 7388/1 knife handle pull nail (commonly called IS0 7388/2-40/50) can be divided into 45 degrees and 75 degrees.
4. ANSI/ASME (American Standard) tool holder pull nail angle is 45 degrees, 60 degrees and 90 degrees.

With regard to thread G of tool holder screw, except for ANSI/ASME (American Standard) tool holder screw which has British thread standard, the other three kinds of tool holder screw all use metric thread, 40# tool holder screw usually uses M16 thread, 50# tool holder screw usually uses M24 thread.

DIN 2080 (NT or ST for short)
DIN 69871 (JT, DIN, DAT or DV) ISO 7388/1 (IV or IT)
MAS BT (BT) ANSI B5.50 (CAT)

The German standard of 1:10 HSK vacuum tool holder is DIN69873. There are six kinds of standards and specifications, namely HSK-A, HSK-B, HSK-C, HSK-D, HSK-E and HSK-F. There are three kinds 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).

Bizimle iletişime geçin

Author:

Mr. jiames.wang

E-posta:

info@qfmh.com

Phone/WhatsApp:

8613705473076