Faster changeover than standard collets and more flexible than master collets and pads, the Hardinge HQC quick-change collet systems offer long life, can accommodate bar stock variation, and provide the opportunity for increased spindle speeds. The flexible collet offers true parallel gripping with the collet segments running parallel to the stock even when there are variations in the stock size. The collet head has a working range of [+ or- ] 1/64". Parallel clamping minimizes stock "push back" and requires less draw bar force than conventional collets. Higher feedrates and spindle speeds are possible. The design of the Hardinge HQC quick-change collet system exerts more gripping force and achieves greater concentricity control than standard collets, master collets and pads, or three-jaw chucks.
Hardinge HQC quick-change collet systems can be changed from one size collet to another size in less than 20sec. This is accomplished by using a manual or hydraulic changing wrench. The wrench compresses the collet, allowing for quick and easy removal, and quick installation of a different size collet head.
Thinking in terms of multi-spindle automatics, the fast collet changeover can be multiplied by six or eight spindles. Because the system requires less draw bar force to adequately grip the bar, it reduces the breakage of closing fingers and pins common when the bar varies beyond the...