Group of three 5C failsafe collet blocks manufactured by Hardinge. Three different gripping methods are shown including a collet, a Sure-Grip expanding collet and a step chuck that will accommodate larger part diameters.
"Parts remain clamped if loss of air occurs when using the Hardinge failsafe collet block (closer)," said a company spokesperson. "Air is required during setup to receive the part, whether using a single collet block or a sub-plate of multiple blocks. After set-up, a unique spring design holds the workpiece with 1,760 pounds of optimum 5C drawbar force. The spring-to-close design provides the opportunity to use pallet shuttles without the need for air or hydraulic lines. If loss of air should occur during the machining process, parts will remain clamped and concentricity will be maintained without downtime, waste or injury.
"Modular units can be used vertically, horizontally or in any position for machining or assembly operations. These units will line up on a trunnion plate for fourth-axis, multiple-part machining with a rotary table."
Each unit has a 5" square footprint with four mounting holes 4" on-center. A 1/8-27 NPT port is located on the back of the unit for connection to shop air. Maximum operating pressure is 75 PSI. Multiple units will connect to a single pneumatic connection, but can have separate valves for controlled workpiece placement during set-up. Custom sub-plates, modular set-ups, valve assemblies and special collets can be provided by Hardinge to meet individual requirements.
The Hardinge thru-hole base design allows coolant and chips to be flushed through rather than building up. This can eliminate the time-consuming process of tearing down and cleaning out the unit, as would be the case with other closed-base designs, the company said.
Unlike other collet block manufacturers, Hardinge also produces the collets and step chucks for use in the collet block, said Hardinge. Standard Hardinge off-the-shelf 5C collets will hold up to 1-1/16" round parts, up to 29/32" hex parts or up to 3/4" square parts. Step chucks can be used to hold parts up to 6" in diameter. Hardinge Sure-Grip expanding collets will grip the part internally for up to 3-1/64" ID part sizes. Dead-length collets offer exact part length control when machining shoulders and faces. The part locates against the face of the collet, the back face of a stepped hole or the face of the work stop to ensure no longitudinal end movement. Manual chucks will also thread onto the spindle nose. Much of this spindle tooling can be shared with other CNC lathes.
"The Hardinge 5C collet block offers peace-of-mind because of the fail-safe design that is built in," said the spokesperson. "This design eliminates the risk of scrapping parts, the danger of parts flying off if loss of air should occur and eliminates downtime associated with chip buildup. Hardinge offers a large selection of pneumatic and hydraulic collet blocks for operating pressures up to 5,000 PSI."
For more information contact:
Hardinge Inc. Workholding Div.