Federal-mogul Wiesbaden Gmbh

Federal Megal Wiesbaden Gmbh + Co. Kg

Gerhard Weil

Maik Wilhelm

Gerd Andler

Thomas Aubele

Andreas Dengler

A method and an apparatus for testing the adhesive strength of overlays attached to the inside of plain bearing bushings. The method is characterized in specifying clearance between the plain bearing bushing tested and a rotating or oscillating pin extending through the bushing. Next, feeding a liquid medium into the gap between the bushing and the pin and oscillating the plain bearing bushing and pin relative to one another perpendicularly to the bushing axis for a given period and examining the bushing after the load test. The corresponding apparatus comprises a pin mounted rotatably in a pin receptacle and on which there is arranged a first drive mechanism. In addition, a bushing receptacle is provided, in which the plain bearing bushing is fitted, wherein the pin is mounted with predetermined clearance in the bushing. The apparatus additionally comprises a mechanism for bringing about oscillating relative movement of bushing receptacle and pin receptacle.

Method and apparatus for testing the adhesive strength of overlays of plain bearing bushings

The invention relates to gudgeon pin bushes which find application in highly-stressed engines, with the problem of a tendency to pit, in particular in the middle regions (with relation to the radial axis of the bush), on starting the motor. According to the invention, the problem can be avoided whereby the friction surfaces of a gudgeon pin bush, at least in the high loading region, have the following parameters measured over the bush cross-section in the axial direction: the support percentage is a minimum of 99.0% to a depth of at most 1.800 m, the depth of the roughness core profile is at most 0.30 m, the proportion of the material Mr1 of the roughness core profile is at most 8%. The gudgeon pin bush can be obtained by finishing the bearing surface of the gudgeon pin bush using a surface machining method.

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Hunfelden, Germany

Gerhard Weil