Abstract: The invention relates to a screwing head, notably intended for installing caps on containers of bottle of similar type. This screwing head comprises an upper bush (8) fixed to the hub (1) and connected by elastic means to a lower bush (2) mounted to slide on the hub (1), these elastic means (5) being designed on the one hand to apply sufficient pressure to engage the bush (2) onto a friction disc (4) fixed to a bottom unit (3) provided with a screwing head and on the other hand to apply a preset torsional torque which, by working in conjunction with cam means, enables the bush (2) to be released from the friction disc (4) when the cap comes to the end of the tightening operation.