We use rolled, calibrated and heat-treated sleeves made by our partner Friesische Verschleißtechnik GmbH. The intended material is special quality manganese hard steel. The ends are parallel and about each other, and one side is chamfered for easier assembly. Calibrating the sleeves after the rolling process guarantees a tight fit, so that sleeves will not be pushed out of the drilling under load.
Bolts and PinsAdmin2020-05-27T11:22:50-05:00