Mapal has upgraded its HTC range of universal high torque chucks by adding temperature compensation that guards against the generation of excessive clamping forces when demanding machining operations are being performed. This makes them suitable for virtually all applications, from roughing to high precision finishing.
All HTC chucks feature a clamping system based on hydraulic expansion. In high volume milling and similarly demanding applications, the tool shank can reach temperatures of at least 170ºC. This heat is transmitted to the chuck and, with conventional HTC chucks, the resulting expansion of the oil in the clamping chambers produces excessive clamping pressure that can overload the chuck. The latest Mapal HTC chucks are designed to eliminate this problem.
All benefits of the existing HTC chucks are retained. They offer high radial run-out accuracy of 3 µm or better, and tool changing simply involves actuating the clamping screw. No special heat shrink equipment is required.
Hydraulic expansion technology with two oil chambers provides damping, which is particularly beneficial during milling operations. High holding forces, which are the hallmark of HTC chucks, and essential for high volume machining, are also unchanged. Due to the special connection technology used for the bore and tool body, and to the matched actuation elements, higher oil pressure is achieved, and this results in higher clamping pressure. This means that HTC chucks can safely transmit torques of up to 500 Nm at a diameter of 20 mm.
Mapal HTC chucks featuring temperature compensation include types with HSK-A 63, HSK-A 100, SK 40 and BT 40 connections. In addition short versions, which are occupy less space after installation, are available with HSK 63, HSK 100 and SK 50 connections. HTC chucks are suitable for clamping tools with diameters from 6 to 32 mm, but reducing sleeves can be used to extend this range without compromising holder integrity.