Abstract: A well pipe elevator comprises a ring having an interior volume and adapted to be fitted over a pipe from above and one or more tongues carried by the ring. The tongue mounted for movement between a retracted position (I) for fitting the elevator to the pipe and a deployed position (III) for retaining the pipe. The tongue projects minimally into the interior volume of ring in the retracted position and maximally into the interior volume in the deployed position. The tongue has a rest position intermediate the retracted and deployed positions. The biasing spring is coupled at one end to the tongue and at the other end to an actuating member. A retractor is provided for controlling the actuating member displaceable between an advanced position corresponding to the rest, intermediate position of the tongue and a withdrawn position corresponding to the deployed position of the tongue.
Abstract: A control device for lifting winches, in particular for drilling rigs, uses an electric motor able to operate in all four quadrants of the torque-speed diagram. A control circuit procures controlled excitation of the electric motor. A manipulator on a control panel controls the control circuit by establishing, according to its position, a given speed request instruction. An indexing circuit for controlling the control circuit is adapted, on the bases of predetermined end of travel positions and a given law relating the speed to the difference in height between a given end of travel position and the actual height at the time in question, to establish a given speed request instruction. A comparator passes to the control circuit only the speed request instruction that it receives representing the lower speed.