Schunk's Rota NCR-A Maintains Grip by Preventing Grease Contamination
The Rota NCR-A, a sealed six-jaw pendulum compensation chuck from Schunk, is designed with seals at the jaw interface and the piston to keep the grease from being washed out.
The Rota NCR-A, a sealed six-jaw pendulum compensation chuck from Schunk, is designed with seals at the jaw interface and the piston to keep the internal grease from being washed out and clamping force from being gradually lost. This is said to ensure precise function even with low clamping forces, resulting in process safety and longer maintenance intervals.
The central chuck piston carries three inner pendulums aligned at 120 degrees. Each pendulum is connected to two base jaws. The workpiece is thus centered between six contact points, which can be adjusted in pairs. This results in optimal workpiece centering without redundant dimensioning because clamping forces are directed toward the chuck. For finish machining or clamping of pre-turned surfaces, users can clamp the pendulums of the Rota NCR-A chuck in center position, and all six jaws can move concentrically. The clamping force between the first and second clamping operation can be varied by the pressure reduction on the clamping cylinder. The rigid chuck body and the long jaw guides ensure a high repeat accuracy and precise machining, the company says.
Schunk’s standard chuck jaws can be used on the Rota NCR-A. The device is available in sizes ranging from 190 to 1,000 mm with maximum clamping forces between 36 and 300 kN and jaw strokes from 6 to 25 mm. The power lathe chucks ranging from 190 to 225 mm are equipped with tongue and groove systems. From size 250 mm on, it is equipped with a fine serration. From size 630 mm on, the chuck can be used on vertical lathes.
The challenge holding tight tolerances for its billet RC helicopter engine components drove this company to develop an innovative fifth-axis tombstone device to complete multiple parts on an HMC in one setup.
Bar pullers are cost-effective alternatives to enable automated turning on CNC lathes. This article explains how they work and how shops can benefit from using them.
Don't assume the standard chuck is the right workholding for every lathe application.