Series 860 and series 861 expansion chucks

Vorwald series 860 and series 861 expansion chucks

The Vorwald series 860 expansion chuck is a standard expansion chuck with individual expansion lugs that is suitable for universal use in virtually any winding process. The simple design ensures a long service life. 
Several types of expansion lug are available
to cover all requirements: longitudinally grooved steel expansion lugs and polyurethane expansion lugs with smooth surfaces or bolted versions with different surface profiles that can be quickly interchanged. The customer’s requirements determine how many expansion lugs there are inside the mantle and where these lugs are placed.
The hardened steel expansion lugs are available with a wide range of different surfaces to ensure maximum torque transmission into the different core materials. All expansion lugs are equipped with a retraction system that ensures that they slide back safely. This makes it easy to slide the cores on and off. Expansion leaves are also possible as an alternative to the expansion lugs. Expansion chucks with expansion lugs or leaves are available for cores with internal diameters ranging from 50 to 500 mm.

The functional principle relies on the use of an inclined plane. Compressed air is fed into the pneumatic chamber, causing the pneumatic piston to push the cone under the expansion lugs like a wedge. The cone and expansion lugs have the same bevel. This creates a radial movement from an axial one. This arrangement provides the expansion chuck with a very large clamping force. Optionally, the expansion chuck can be equipped with a hydraulic pressure booster (series 861) that further increases the clamping force. Another very important advantage of this arrangement is that the clamping of the cores is perfectly centred, as all expansion lugs expand evenly. This enables very high winding speeds to be achieved.
The mantles of the expansion chucks can be made from a large number of materials with various wall thicknesses – depending on the customer’s application. The expansion chucks are based on the Vorwald standard and are custom-made using a modular concept.

Options

• Flange or bearing shaft according to customer requirements
• Available with and without hydraulic booster
• Expansion lugs or leaves with various surfaces
• Quick adjustment to different core diameters using adapters
• Special dimensions are available on request

Benefits

• Transmission of the highest possible torques
• Perfectly centred core clamping
• Quick clamping and unclamping