Disc Springs – Design, Function, and Applications in Mechanical Engineering
Disc springs are standardized machine components that ensure a positive-fit torque transmission between the shaft and the hub. Their semicircular shape has earned them the nickname “Woodruff key,” a term also frequently used to describe them. In direct comparison to conventional keyways, disc springs are primarily used where design constraints, tapered shafts, or short hub lengths necessitate an alternative solution. In manufacturing, we adhere strictly to DIN 6888 and SAE standards and offer disc springs with or without heat treatment. These designs are available from stock in a wide variety of materials.
What is a disc spring?
Disc springs are semicircular fasteners that fit into a radially milled groove on the shaft. The corresponding groove in the hub is straight, which helps ensure an optimal connection. When the hub is pushed onto the shaft, the disc spring automatically straightens out and engages positively in the hub groove. Disc springs are manufactured according to a standardized process in accordance with DIN 6888, so that dimensions, tolerances, and applications are defined in advance. However, if needed, you can also purchase custom-made disc springs in various sizes from us.
Typical applications for disc springs
Disc springs are primarily used in general mechanical engineering, but can also be employed in instrument and precision engineering. They are sometimes used in engine and transmission manufacturing as well, for example as supplementary components in automotive parts. In these applications, they serve primarily as assembly aids or positional locks rather than as primary torque transmission elements.
Disc springs / Woodruff keys
Interesting facts about our disc springs
Available dimensions according to DIN 6888
| Height | h | 1,40 - 16,00 mm |
| Length | l | 3,82 - 43,08 mm |
| Width | b | 1,00 - 10,00 mm |
Available dimensions according to SAE
| Height | h | 0,203 - 0,641 inch |
| Length | l | 0,500 - 1,500 inch |
| Width | b | 0,625 - 0,375 inch |
What standards and dimensions are available for disc springs?
Disc springs are generally standardized according to DIN 6888. They are therefore designated by their dimensions, which can vary and can also be customized by us upon request. The size you need for your machines depends primarily on the shaft diameter of the equipment. Materials such as quenched and tempered steel (primarily C45), case-hardened steel, and stainless steel (especially in corrosive environments) are typically used for manufacturing; however, there are also numerous customization options available here. Since the shaft cross-section is reduced by disc springs, the groove is comparatively deep. This should be taken into account during design.
What is the function of a disc spring?
Disc springs are primarily used to transmit torque and maintain the angular position between a shaft and a hub. The forces are ultimately transmitted via the flank pressure that occurs on the sides of the disc spring. As with keyways, disc springs do not absorb axial forces. The technical advantage of the disc spring lies primarily in its mobility within the shaft groove—this allows for the compensation of slight angular misalignments or tolerances during installation. This advantage is particularly relevant for classic tapered connections.
Advantages of disc springs at a glance
Disc springs are a good and economically sensible solution, especially for simple applications with a moderate number of torque cycles. However, the advantages go beyond that:
- Easy to install: Disc springs are very easy to install on tapered shafts and short hubs
- Self-centering: Thanks to their semicircular shape, disc springs are self-centering and integrate seamlessly into the machine
- Compact: The compact design of disc springs makes them highly suitable even in confined spaces
- Standard component: Standardized disc springs are cost-effective and easy to produce—even in custom designs
Buy disc springs to DIN 6888 and custom-made products online
Looking to buy disc springs online? Then Crummenerl GmbH is the right place for you—because we offer not only standard disc springs to DIN 6888, but also custom-made products tailored precisely to your company’s needs. Since 1955, we have specialized in the manufacture of components for gearboxes, machinery, and railway technology.
As a result, we have extensive experience in CNC machining of a wide variety of components. All common materials are available from stock, allowing us to fulfill your orders quickly and efficiently. Even custom-made products can be produced in the shortest possible time.
We maintain a high degree of precision during production and always adhere to the customer and drawing specifications provided to us during the ordering process. Do you have any questions about our disc springs?
Please feel free to contact us directly via our contact form to receive a customized quote.