Abstract: An automatic gripper, useful especially for gripping and holding drilling rods on a drilling rig, has a chassis with a front end in the form of a fork equipped with retractable jaws (50). The jaws are retracted by pushing contact with a drilling rod (40) when the rod enters the fork, whereupon a return mechanism (72) automatically restores the jaws to a closed position. The chassis is held fixed on a horizontal pivot axis by rupturable pins or the like. The pins rupture to permit the chassis to pivot when subjected to a predetermined torque, with friction members being provided to frictionally limit the pivotal movement of the chassis. The gripper is thus protected against damage from impacts with the rod lifting mechanism of the drilling rig, for example.

Abstract: The arrangement to which the invention pertains consists of a combination of calibrated compressible components (15), such as washers arranged in stacks, situated between an element (13) secured to the platform and another element (11) secured to a mounting which provides support for jacking mechanisms, accompanied by a sensor device (24) positioned according to the same conditions. The movable core (25) for the aforementioned sensor (24) is attached to a sliding element (21), which, in turn, is attached to the element identified as (13). Under these circumstances, the movable core (25), according to the positions which it may occupy, can modify connections for windings within the sensor. Data obtained in this manner is transmitted by a cable (28) to recording devices, as well as to direct reading devices or to indicators. Application for ocean platforms, notably for offshore drilling platforms.