Thermal Shrink Fit Tool Holder, also referred to as Heat Shrink Tool Holder or Thermal Expansion Holder, is a high-precision and high-performance tool clamping device that operates on the principle of thermal expansion and contraction. It achieves a high-rigidity and high-concentricity connection between the tool and the holder through a scientific heat management process, making it an indispensable component in high-speed machining and precision manufacturing. Common models include BT30, BT40, BT50, and HSK types, each designed for different machine interfaces and processing scenarios.

The holder is manufactured from special stainless steel material with a significantly higher coefficient of thermal expansion than conventional steel. During the heating process, the clamping hole of the holder expands in diameter due to thermal expansion, allowing the tool to be inserted easily. After natural cooling or the application of a cooling medium, the holder gradually contracts, forming a uniform and powerful clamping force around the tool. This mechanical self-locking method not only avoids stress concentration issues common in traditional clamping mechanisms but also significantly improves system rigidity and dynamic balance performance.

Since there are no intermediate components (such as collets or nuts) involved in the clamping process, thermal shrink fit holders exhibit exceptional concentricity and dynamic balance characteristics, making them particularly suitable for high-speed machining environments exceeding 10,000 rpm. Additional advantages include excellent vibration damping, extended tool life, good interference avoidance (enabling multi-axis machining in confined spaces), and highly repeatable clamping accuracy.

These holders are widely used in demanding industries such as aerospace, precision mold manufacturing, and automotive component processing. They support a variety of machining operations including high-speed milling, precision drilling, heavy-duty cutting, reaming, and micro-machining. With the growing demand for high-speed machine tools and efficient processing, thermal shrink fit holders have become a critical core technology in modern intelligent manufacturing systems due to their significant performance advantages.