OLICNC TAKING ABOUT Basic knowledge of tool holder (3) Shrinking tool holder and hydraulic tool holder OLICNC

In the first two lectures, (1) the connection between the tool holder and the spindle, the application scope of different spindles, and their respective advantages and disadvantages; (2) the difference between the 6 different interfaces of the HSK tool holder. Today we will talk about the contact part between the tool holder and the tool. Generally speaking, it can be divided into face milling tool holder, ER. spring tool holder (including TG chuck, MEGA clip, SK clip), CAP. strong clip Holder holders, side mount holders (2 degrees EM. and WN. bevel), DC. drill chuck holders, Morse taper holders, threaded connection holders, SRK. Shrink holders and MHC. Hydraulic holders Wait.

At present, it should be ER. spring tool holder, thermal expansion tool holder and hydraulic tool holder, which are used the most.

(3) Talk: The difference between the thermal expansion tool holder and the hydraulic tool holder is compared and analyzed from the principle, clamping accuracy and application range:

Ⅰ. Principle

The principle of thermal expansion tool holder is to use the difference between the thermal expansion coefficient of the tool holder and the tool to strongly clamp the tool. The system uses an intelligent heating machine for heating and clamping, and the tool loading and unloading is simple and convenient. The tool mounting section does not have the nuts and parts required for collet chucks. Simple and efficient, the shape of the slender shank head can set the protruding length of the tool more practically, and it can better reflect the advantages of the heat shrinkable shank in the process of deep cavity machining, stable clamping during high-speed machining, high concentricity to maintain higher machining accuracy.

The principle of the hydraulic tool handle is to insert a hexagonal wrench, tighten the bolt ①, and the piston pushes the hydraulic medium ② to squeeze into the oil cavity, so that the expansion wall of the tool handle expands, and the tool ③ is held tightly to achieve clamping. Since the medium in the oil chamber is liquid, the pressure is uniform, so the tool is used to ensure that the tool is in the center of the tool handle during the entire clamping process, which ensures a good clamping accuracy. The result – absolutely precise clamping accuracy and repeatability, strong clamping force and good running stability.

Shrink shank

hydraulic tool holder

advantage:

Large clamping force, high rigidity, strong and stable cutting, no chattering, high-quality machined surface, high precision during runout, effectively extending tool life, no fastening parts (nuts, collets, etc.), and skilled Regardless of the degree, it can be installed accurately and with high precision, the price is relatively affordable, and the application range is wide.

advantage:

Good clamping stability, easy to operate, can clamp tools of different diameters through the reducer sleeve, no other auxiliary installation tools are required.

shortcoming:

A special heating instrument is required to install the tool holder. The price of the hot-swelling tool holder is about half lower than the price of the hydraulic tool holder. In dry cutting, the precision and clamping force of the tool will decrease after heating, so it is necessary to use air cooling or water cooling in use. better.

shortcoming:

The price of the hydraulic tool holder is higher than that of the thermal expansion tool holder, and there is a limit to the clamping length of the tool. The depth of the tool must meet the depth of the expansion wall of the tool holder, otherwise the oil cavity will be broken. Not suitable for ultra-high-speed finishing

A damaged handle is basically irreparable.

Damaged hilts can be repaired unless the oil cavity bursts.

Ⅱ. Clamping accuracy

Compared with other tool holders, the thermal expansion shank material has a high thermal expansion coefficient, which can realize low temperature hot clamping and hot extraction. No matter how many times of hot-clamping and hot-removing operations are performed, the material will not change and the accuracy of the tool holder will not deteriorate. The high-rigidity tool has a short protrusion, and the shrink-fit tool holder does not require a nut and a collet for clamping the tool. It is an integral type composed of only the body. The half angle is 3°, and the wall thickness is 1.5mm. It is very light and slender. shape, try to avoid interference with the workpiece.

High rigidity, strong and stable cutting, no chattering, high-quality machined surface, high precision during runout, effectively extending tool life, no fastening parts (nuts, collets, etc.), regardless of proficiency, can be Accurate and high-precision installation: Because there is no need to adjust the clamping degree, the tool can be installed with high precision, and the high-precision clamping can prolong the tool life. There is no change in accuracy during hot loading and unloading, and the stability is stable and reliable.

The hydraulic tool holder has high speed and good rotation accuracy, and the rotation accuracy and repeated clamping accuracy are both less than 0.003mm. The overall structure is compact, and the effective clamping force is strong. The overall precision of the tool holder is high, which increases the tool life by 4 times. Good running stability. There are a variety of interface forms, which can be adapted to a variety of machine tools, and can process products with high precision and high surface quality.

Good damping and vibration reduction performance, in the process of processing, the damping characteristics of the hydraulic oil chamber reduce the generation of vibration. There is no vibration, so that the performance of the tool is well played. It increases the life of the tool and the tool holder, and significantly improves the surface quality of the processed product. It is convenient and simple to install the knife, no other auxiliary equipment is required, just a hexagonal wrench, tighten the pressure bolt, and the knife is installed. No other auxiliary equipment and maintenance are required. Quick tool change, which can be completed in seconds, reducing downtime and improving production efficiency. It can be adapted to most production occasions, and tools of different diameters can be clamped through the reducer sleeve, which saves costs.

Ⅲ. Scope of application

Due to the relatively thin wall thickness of the thermal expansion tool holder, it can prevent interference with the processing of certain parts, which is almost the same as the tool diameter. In machining, hydraulic tool holders are used more often. However, with the different changes and updates of materials, aviation aluminum and aluminum-magnesium alloys are used more and more, lightweight design of the body, and new automobile production lines have begun to use more and more thermal expansion tool holders.