Shrink Disc

Micromech supplies WITTENSTEIN alpha shrink discs for secure, backlash-free shaft-to-hub connections. Designed to transmit torque without keys or splines, they provide a compact, reusable and straightforward mounting solution for hollow-shaft and mounted-shaft gearboxes.

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Description
Features
Specifications
Downloads
Certifications

WITTENSTEIN alpha shrink discs provide a secure, backlash-free connection between hollow-shaft or mounted-shaft gearboxes and the driven shaft. The friction-locking connection transmits torque without keys or splines, supporting accurate and reliable operation across demanding servo-drive applications.

Designed to match WITTENSTEIN alpha gearboxes both technically and geometrically, the shrink discs provide high true-running accuracy and smooth operation while requiring minimal installation space. Their two-part construction and straightforward bolt-tightening arrangement simplify fitting and removal.

The shrink discs can be reused multiple times when correctly installed and maintained. Standard steel, chemically nickel-plated and stainless-steel versions are available, providing options for standard industrial environments and applications requiring increased corrosion resistance.

The range supports WITTENSTEIN alpha SP+, SPK+, HG+, VDH+ and VDHe gearboxes. Versions for alpheno® and PKF gearboxes are also available on request.

Typical applications include:

Hollow-shaft gearbox connections
Mounted-shaft gearbox installations
Servo-driven machinery
Conveyor and lifting systems
Packaging equipment
Material-handling machinery
Rotary positioning systems
General industrial automation

Need help selecting the right shrink disc?

Micromech can help specify the correct WITTENSTEIN alpha shrink disc for your gearbox, load-shaft diameter, torque requirement and operating environment. Talk to an Expert

Features

Secure, backlash-free shaft connection
Reliable torque transmission without keys or splines
Designed for hollow-shaft and mounted-shaft gearboxes
Technically and geometrically matched to WITTENSTEIN alpha gearboxes
Compact, space-saving construction
High true-running accuracy
Smooth operation under dynamic loads
Simple mounting and removal
Reusable two-part design
Standard steel versions available
Chemically nickel-plated versions available
Stainless-steel versions available
Corrosion-resistant options for demanding environments
Suitable for SP+, SPK+, HG+, VDH+ and VDHe gearboxes
Versions for alpheno® and PKF gearboxes available on request

Specifications

Specification	Details
Compatible gearbox series	SP+, SPK+, HG+, VDH+ and VDHe
Additional compatibility	alpheno® and PKF versions available on request
Shrink-disc inside diameter	18 to 68 mm
Shrink-disc outside diameter	44 to 115 mm
Construction	Two-part shrink disc
Connection type	Backlash-free friction-locking connection
Material options	Standard steel, chemically nickel-plated or stainless steel
Required quantity	One shrink disc per gearbox
Recommended load-shaft tolerance	h6
Maximum shaft surface roughness	Rz 16
Minimum shaft yield strength	Rp 0.2 ≥ 385 N/mm²
Supply	Ordered separately from the gearbox

Available shrink-disc sizes and article codes depend on the selected gearbox series and frame size. Installation must follow the tightening sequence and torque values stated in the WITTENSTEIN operating instructions.