Abstract: A structural reinforcement for a hollow member comprising a rigid reinforcing member having a shape that substantially conforms to the cross section of the hollow member to be reinforced with an expandable adhesive material over at least a portion of the surface of the structural reinforcement having one or more extensions on its external surface which control and direct the direction in which the adhesive material expands to bond the reinforcing member to the internal surface of the hollow member, some of the extensions also provide improved reinforcement.

Abstract: A dynamometric measuring device for a drill pipe which includes, firmly attached to the rotating pipe, sensors disposed in a groove on the pipe and electronics for conditioning the signals supplied by the sensors. The measurement signals are transmitted by a commutator-fixed brush assembly to a fixed, non-rotating part. By providing follower-amplifiers of very low output impedance on the commutator, rotating, portion of the assembly and follower-amplifiers of very high input impedance on the fixed brush side of the assembly, the transmission of signals is carried out at zero current. To assure high quality signal analysis, a separation circuit on the fixed brush side of the assembly separates the DC and AC components of the signal prior to transmission to the surface.

Abstract: The disclosure relates to measurement of the rate of advance of a drill bit from a floating drilling installation. The process includes joining a point of the drilling system, fixed in translation with the movement of the drill string, at the lower extremity of which is a drill bit, to a fixed point solid with the ground, by a cable of constant length passing through a pulley system fixed to the floating drilling installation, to measure the angular displacements of different pulleys of the pulley system and to derive from them magnitudes representing the rate of advance of the drill bit. This procedure, applied to a floating drilling system, eliminates the effect of vertical movements, that is swells or waves, from the measurements.