Nyckelinfästningar

Nyckelinfästningar, often translated as keyways or keyseats, are standardized grooves or slots machined into a shaft or hub. These are designed to receive a key, a metal component that fits snugly into both the shaft and the hub. The purpose of a key and keyway system is to create a positive mechanical connection, preventing relative rotation between the two components. This is crucial for transmitting torque in machinery.

The common types of nyckelinfästningar include rectangular, square, and Woodruff keyways. Rectangular and square keyways are typically milled parallel to the shaft's axis, with the key having corresponding rectangular or square cross-sections. Woodruff keyways, on the other hand, are semicircular slots cut into the shaft. This design is often used for lighter duty applications or where ease of assembly and disassembly is important.

The selection of a particular type and size of nyckelinfästning depends on factors such as the amount of torque to be transmitted, the shaft diameter, the material properties of the shaft and hub, and the operational environment. Proper fit is essential; a loose keyway can lead to fretting and premature failure, while an overly tight fit can cause stress concentrations. Standards, such as those from ISO or DIN, often define the dimensions and tolerances for common nyckelinfästningar. These systems are fundamental in mechanical engineering for ensuring reliable power transmission in a wide array of applications, from simple gears to complex industrial machinery.