The principle of heat shrink tool holder is to use the difference in thermal expansion coefficient between the tool holder (special tool steel) and the tool (carbide or high-speed steel) to clamp the tool with high force and precision. The precision of heat shrink tool holder is <3μm, which is no less than that of hydraulic tool holder. Heat shrink tool holder generally needs to be used with heat shrink machine when installing tool. The commonly used heat shrink machine is electromagnetic induction heat shrink machine.
When using an electromagnetic induction heat shrink machine to heat the heat shrink handle, the installation can be easily achieved according to the specifications of the stop disk corresponding to the clamping. The main purpose of the stop disk is to determine the heating position of the handle according to the clamping diameter.
When heating, the temperature of the handle facing the induction coil area is the highest, and heat is conducted to the upper and lower parts of the handle at the same time. When the handle expands (the expansion amount is usually about 3‰-5‰ of the clamping diameter), the tool is installed. During the installation process, it can be used together with the handle overhang length adjustment device, and then cooled to complete the installation.
It should be noted that although the heat shrink machine is equipped with a manual heating mode, it is recommended that if the temperature is not very well controlled, try to use the automatic heating program of the heat shrink machine (heating parameters of different handle suppliers are fine-tuned and stored). When using manual heating, due to the heat conduction time difference between the handle end face and the induction position (0.5-1s), when the handle end face reaches the temperature and expands, the induction coil handle area is actually overheated. Frequent temperature exceeding 500° will affect the service life of the heat shrink handle.
If you are worried about the wrong parameter selection during hot installation, or the overheating of the tool handle caused by misoperation, it is recommended to use Diebold Daibo automatic intelligent temperature control heat shrink machine US1100 for heat shrinking. Diebold US1100 heat shrink machine uses intelligent temperature control induction coil, which can detect the temperature of the tool handle at any time. When the temperature reaches the hot installation temperature, it automatically stops heating and the tool handle will not overheat.
If it is a small diameter heat shrink tool handle, such as φ3-φ5, it is recommended not to use high-speed steel tools, because the thermal expansion coefficient of high-speed steel tools and tool handles is relatively similar, and it is easy to make it difficult to install small diameter tool handles during hot installation.