Abstract: An installation for assembling two parts adapted to be telescoped one into the other, of which at least one part has a radially directed projection which, during assembly of the parts, engages into a correspondingly constructed recess of the other part, whereby the first part is nondisplaceably arranged and the second part is aligned with the first part, and finally the second part during rotation threof about its longitudinal axis and simultaneous axial displacement is assembled with the first part; the second part is thereby positioned by a retaining mechanism which positions the second part with respect to the first part in relation to the joining axis while a threaded spindle adapted to be driven by a motor and held by a rigid support cooperates with the second part by way of a spring-loaded compression mechanism; the threaded spindle is thereby equipped with a slippage clutch.