Faster changeover than standard collets and more flexible than master collets and pads, the HQC Quick-Change Collet Systems by Hardinge offer long life, can accommodate bar stock variation and provide the opportunity for increased spindle speeds.

The flexible collet head 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 ±1/64:. Parallel clamping minimizes stock push back and requires less draw-bar force. Higher feed rates and spindle speeds are possible. According to Hardinge, with its unique design, the HQC Quick-Change Collet System exerts more gripping force and achieves greater concentricity control than standard collets, master collets and pads, or 3-jaw chucks.

20-Second Changeover

Hardinge HQC Quick-Change Collet Systems can be changed from one size collet to another size in less than 20 seconds. 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 range of a standard solid collet or master collet with pads. HQC collets are available for multi-spindle automatic screw machines, Hardinge collet-ready CNC lathes and chuck-style lathes.

The HQC collet heads are designed with special replaceable inserts that form a seal while holding the collet segments together. The seals protect the spindle, collet body and draw tube from chips and coolant. The HQC patented slot-seal system eliminates the need to return the collet to the manufacturer to have the seals changed or re-vulcanized. The seal (inserts) can be replaced in the shop, by the machine operator, further reducing operating costs.

HQC Quick-Change Collet Systems can be used on chuck-style lathes to replace 3-jaw chucks. The reduction in weight and the unique, efficient design of the HQC System allow you to increase the spindle rpm without any concern for centrifugal forces. Hi-tech cutting tools, along with faster speeds and feeds, can boost your productivity. According to Hardinge, chucking forces are higher than jaw chucks and even higher than solid standard and master collets; the interferences associated with jaw chucks are nonexistent with the clean contours of the Hardinge system.

The HQC system is shorter than standard collet adapters, gaining more working area. Machining closer to the spindle results in better total indicator reading (TIR) on finished parts.

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