Coupling device for connecting a towing vehicle to a semi-trailer, and process for the modification of used couplings

摘要

Coupling device for connecting a towing vehicle to a semi-trailer, with a king pin (20) on the trailer and a tractor coupling on the towing vehicle, the trailer coupling having locking members for positive and rotatable engagement of the rotationally symmetrical surfaces (26,27) of the king pin (20), the surfaces (26,27) being formed by the outer surfaces (46) of a sleeve (30) thermally coated with a wear-resistant layer (41,42) and seated rotatably on the king pin (20). A method of modifying used couplings of this type is also claimed.