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Shrink Fit System

Shrinking Technology Measuring Adaptor The tool length is pre-set before the shrinkprocess by means of the measuring adaptor (B). This is inserted into the chuck (A) together with the tool (C) and then withdrawn a distance l

C

2 to enable the subsequent overalltool length to be calculated. The axial stop screw is then screwed in or out by turning the adjusting element, thereby pre-setting the tool length. The adjusting element is then removed and the chuck can be contracted to clamp the tool.The retention torques in the shrink chucks arehigher than with any other known clamping system. Although this type of clamping represents a releasable connection, the retention force is so great and the tool assembly vibration so low that it behaves almost like a solid tool.The runout of the adaptors with the clampedtools is also equivalent to that of a solid tool. Inadvertent release of the tool, particularly when milling on high-speed machining centres – a known problem with other clamping systems – is a thing of the past with this system.KENNAMETAL HERTELshrink chucks aresuitable for both HSS and carbide tools. The short chuck heating-up phase means that the tool does not have time to heat up, even if its expansion coefficient is the same as that of the chuck. The use of a particularly heat- resistant tool steel and proprietary tempering processes means that the chuck retains its runout and elasticity even after a large number of shrinking cycles (>5000).The maximum temperatures that occur duringclamping of the tool by shrinking, around 300 to 340°C, are well below the temperature that could provoke a structural change in this material.

B

l 2

A

Die and Mould - 7354 C

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