EXPANDING COLLETS OFFER SOLUTIONS TO DIFFICULT MACHINING PROBLEMS

Expanding collets and between-center arbors grip the internal diameter of a part for turning, milling, grinding, assembly, inspection and automation applications. When the OD (outside diameter) of the part is hard to grip, or cannot be gripped, internal gripping may be your answer, if there is an internal diameter in the 1/8-in. to 4-in. range.

During chucking operations, parts can be located against the face of the arbor or against a machineable workstop. This provides exact length control, as well as improved consistency. The expanding collet draws the par t fir mly against the stop, producing an extremely stable location. Longer parts can be easily machined due to this added stability. The results are heavier cuts, better surface finishes and closer tolerances when using a workstop. Workstops may not be necessary if you are only machining the OD of the part.

Hardinge manufactures Sure- Grip Expanding Collet Systems with interchangeable collet heads that have an under-over capacity of -0.0001 in. to +0.015 in. from its specified size to accommodate a range of part diameters. A double-angle design assures true parallel gripping with maximum grip force. Parallel gripping means that the collet expands equally over the entire length of the collet, rather than just at one end of the collet, for maximum bearing contact against the part. This results in greater stability and better part accuracy. Parts are instantly centered and located without adjustment. Higher rpm and greater federates deliver more parts per hour, and a built-in safety stop will prevent the collet from over-expanding. Machines with ANSI type-A spindles and machines with collet-ready spindles or collet adapters can use the Hardinge Sure-Grip Expanding Collet Systems.

Hardinge A2-5 5C Sure-Grip Expanding Collet Systems.

The 5C, 16C and 3J collet-style expanding collet systems mount directly into the collet angle of the spindle or in fixtures such as collet blocks with instant centering. The one-piece spindle arbor construction and the closing mechanism hold the workpiece extremely rigid for superior surface finishes and concentricity. A2-5, A2-6 and A2-8 expanding collet systems mount directly on to the spindle. Hardinge precision manufacturing processes guarantee the Total Indicator Reading (TIR) of the arbor will be within 0.0002 in. With the expanding collet mounted on the arbor, the TIR of the collet and arbor will not exceed 0.0005 in., without the need for adjusting screw and indicating.