FORKARDT delivers the World's Largest Power Chuck

SIZE DOES MATTER, and FORKARDT has the largest! Once again, FORKARDT has proved capable of delivering world-leading solutions for both small and large workholding problems. The latest example of FORKARDT engineers demonstrating their prowess is with the December 1998 delivery of the 12 WAZK 4000 Power Chuck. This chuck will be used by LIEBHERR in Biberach, Germany, for the manufacture of bearing housings. It is not surprising the FORKARDT engineers are proud. The chuck is 4,000mm in diameter, weighs c.20tons and, as such, is the largest power chuck in the world.

So yet again, FORKARDT has demonstrated its ability to solve customers' demanding workholding problems. The WAZK 4000 12-jaw power chuck is the result of a close co-operation between the end-user and FORKARDT engineers. It permits very quick and highly accurate power clamping of large, thin-walled components. Previously, these large, difficult to handle, and yet accurate components, required considerable manual intervention by highly skilled operators, not least to ensure the components were correctly clamped, even on relatively simplistic clamping plates.

Needless to say, the manufacture of both the inner and outer bearing housings of this type is an extremely complex and demanding manufacturing process requiring considerable experience. The problem of clamping these thin ring-shaped components is especially demanding of the designers of a chucking system, not only because of the size of the components, but also due to their relatively thin section and ease of deformation. All these factors make the design and manufacture of a successful clamping system even more challenging (but FORKARDT relishes a good challenge!).

For example:

• To ensure the workpiece does not deform, all 12 jaws must very accurately, independently and consistently clamp the workpiece (even if it is still a piece of raw material and does not have a perfectly round shape).
• At the same time, the chuck must be able to grip the component sufficiently tightly to facilitate accurate and fast machining, but without deforming the workpiece at any of the available rotation speeds.

• To further facilitate precise machining of the components, it is essential to ensure the component is gripped centrally, with fine adjustment of the clamping pressure in order to achieve the high cutting speeds necessary
• Furthermore, the centrifugal force compensation of the jaws must not in any way adversely influence the accuracy of the machining process.

The unique solution provided by FORKARDT is based on an highly innovative, strong and yet high precision clamping mechanism, built into the chuck. This mechanism ensures the optimum operation of the 12 jaws, even on components which, at the start, are not completely round. At the same time, the component can be accurately centralised along the main axis of the vertical turning machine.

Technical Highlights:

To provide energy for all the operating functions of the chuck, a special hydraulic cylinder has been integrated into the underneath of the chuck body.
Furthermore, a special control system activates the electronic adjustment of the clamping pressure. This system provides individual levels of compensation to suit the differing production situations which exist across the entire spectrum of the system's machining capabilities.

All of this design and manufacturing expertise combines together to enable FORKARDT to deliver a cost-effective and high quality solution which will enable the customer to achieve higher levels of precision and high productivity. Ultimately, the customer has received a unique product providing considerable flexibility and accuracy in the solution of an extraordinarily difficult workholding problem, while FORKARDT has once again proven its world-leading capability.

The message for you is equally clear. FORKARDT has been delivering innovative solutions to complex workholding problems for the last 75 years. FORKARDT's technical capability started out strong, and is even stronger today. FORKARDT continues to generate innovations which lead the workholding world forward. If your Company wishes to improve its productivity through innovative workholding, then contact FORKARDT INTERNATIONAL - the experts.

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