Rundlaufprüfung

Rundlaufprüfung is a German term that translates to "runout test" or "circular runout test" in English. It refers to a metrological inspection used to measure the deviation of a rotating surface from a perfect circle. This test is crucial in manufacturing and engineering to ensure the quality and precision of rotating parts such as shafts, gears, bearings, and wheels.

The principle behind a Rundlaufprüfung is to establish a fixed reference point and measure the variation in distance from that point to the rotating surface as it completes a full revolution. This is typically achieved using a dial indicator or a precision electronic sensor. The part to be tested is mounted on a precision bearing or centers, and the measuring instrument is positioned to touch the surface being checked. As the part rotates, the indicator will show the extent to which the surface deviates from its ideal circular path.

There are two primary types of runout measured: radial runout and axial runout. Radial runout measures the deviation perpendicular to the axis of rotation, indicating how much a cylindrical surface wobbles. Axial runout, also known as wobble, measures the deviation parallel to the axis of rotation, indicating how much the face of a rotating part deviates from being perfectly perpendicular to the axis.

Performing a Rundlaufprüfung helps identify manufacturing defects, imbalances, and wear, which can lead to vibration, noise, premature failure, and reduced performance in machinery. It is a standard quality control procedure in industries where precision and smooth operation of rotating components are essential, including automotive, aerospace, and machine tool manufacturing.