Abstract: The invention relates to a process for improving the characteristics of a fluid and in particular of a cement slurry for the cementing of wells, particularly of oil wells, wherein it consists in applying to this fluid an energy of between 4.8 and 6.3 kJ/kg, by incorporating adapted pressure drops, in line, before the well head and at the outlet of a high-pressure pump, said pressure drops being substantially independent of the flowrate. The invention also relates to a device for carrying out this process.

Abstract: The invention relates to the improvement by a chelating agent of polymer compositions usable in particular in the hydraulic fracturing of underground formations close to a drilling well. The chelating agent is a compound such as fumaric acid, maleic acid or thiourea. Substantially shorter crosslinking time; use possible even with sea water or a brine.

Abstract: The invention relates to an additive adapted to suppress free water in conditions of "over-dispersion" of the cement when cementing an oil well. This additive is selected from cerain metal soluble salts such as Mg, Ni, etc. This additive modifies neither the other properties of the slurry (in particular setting time) nor the action of other additives (in particular of retarders).

Abstract: An aqueous solution of a terpolymer, useful as fluid loss agent for drilling muds and not for cement slurries, is treated with acid and heat. An excellent fluid loss agent for cement is obtained. Very efficient liquid additive, for all purposes, which does not modify either the rheology, nor substantially the setting time.

Abstract: The invention relates to a quick-release coupling, more particularly intended for hose pipe assemblies used at sea.Said coupling is composed of two jaws which cooperate with truncated parts of the coupling members and are held together or released by the movement of a finger sliding inside bores provided in said jaws.The coupling according to the invention offers improved efficiency and reliability.

Abstract: The invention relates to cement compositions for cementing wells, which allow pressure gas-channeling to be effectively controlled up to more than about 485.degree. F. The cement composition contains a styrene-butadiene latex and a stabilizer. The film of latex interrupts gas-channeling after an extremely brief path.

Abstract: A machine is of the type comprising an oscillating movable head with a tool-holding spindle, driven in rotation above a lens-support. The lens-support is borne by a vertically movable spindle which is mounted inside a sleeve, flared out at its upper part to form two bearing surfaces and, the lens-support comprises a ledge which surrounds the part of the sleeve containing the bearing surfaces. The lens-support rests on a head mounted for free rotation in a fixed pivot so that when the spindle is moved upwardly, the lens-support is immobilized in a horizontal position, to deposit the lenses to be polished thereon, or to remove them after the polishing operation. When the spindle is moved downwardly, the lens-support, then at a distance from the bearing surfaces, can oscillate freely during the lens-polishing operation, under the effect of the movable oscillating head.

Abstract: The invention relates to a method for obtaining gelled hydrocarbon compositions, and their application in the hydraulic fracturing of rocks.The gelling method according to the invention uses as an activator a partially neutralized aluminum acid salt.

Abstract: The jumping suit is for a parachutist taking part in competition or sport with a group of parachutists. Suit holding and retaining means are provided on the suit on the outer side of the arms and legs of the parachutist in the form of beading which is fixed to the suit fabric and forms an outer rib capable of being taken hold of by the hand of an adjacent parachutist.

Abstract: A method and an apparatus to wind a thread on a succession of reels carried by coaxial annuli provided with a clamp member to couple the thread to the reel, the switching-over of the thread from a filled reel to an empty reel being initiated after the detection, by way of a detector, of a predetermined angular position with respect to an associated anvil of the clamp member fixed on the annulus carrying the empty reel.This method and apparatus are for example used to wind electric insulated wire comprising a metallic core around reels.

Abstract: An apparatus and a method to wind a thread on a succession of reels, comprising two crown wheels or annuli having parallel and nearly horizontal axes, each of them supporting a coaxial reel, a traversing mechanism having a movable pulley displaced above the reels and able to feed the thread in regular layers, means being provided to cut the thread after the winding of a first reel and means to then ensure continuously the winding of the thread around a second empty reel.The apparatus comprise a first movable catch pin being positioned near the empty reel to ensure the gripping of the thread, to allow the cutting of the thread and the coupling of this thread around said empty reel, a second movable catch pin placed near the full reel to grip and maintain the thread perpendicularly to the axis of the full reel after the cutting of thread, and means to control the position of the catch pins at the end of the filling of said first reel.

Abstract: Jumping garment for a parachutist in which means are incorporated for increasing the drag during the free fall. The drag-increasing means comprise openings formed in the wall of the garment in at least one of the sides of the body. The openings are adapted to allow direct entry of air into the space defined by the garment around the body of the parachutist so as to fully inflate the garment.

Abstract: The device comprises a first gripping band of the Velcro type which is secured to a first of the parachute pack flaps and engages a second gripping band of the Velcro type secured to a second pack flap opposite the first flap. The pack is opened by an opening control device which is connected through a flexible connecting element to an edge of the second gripping band in such manner that a pull on the opening control device causes the second gripping band to be disengaged by peeling off from the first gripping band in starting from the edge. In an alternative arrangement, the first and second gripping bands are interconnected not directly but by an independent gripping band which is disengaged by peeling off from the first and second gripping bands for opening the pack. The opening control device may be an automatic pack opening strap coiled on the pack.

Abstract: Buckle for retarded automatic unlocking of safety belts and harnesses of parachuting equipment or of vehicles, which comprises a frame slideably mounted in a casing and a shaft in the frame for supporting a swinging bolt adapted to imprison the shackle of a strap, or release either instantaneously under the direct action of a manual control means or with a delay under the action of an automatic control means connected to the bolt and actuated by springs compressed by the shackle when the shackle is introduced inside the casing. The automatic control means is itself locked by means adapted to be slowly withdrawn, by means of a brake, under the action of a traction force exerted by the shackle on the bolt providing the sliding movement of the frame against the action of a return spring bringing back the frame to its initial position as soon as the traction force of the shackle on the strap substantially diminishes or ceases.

Abstract: Buckle for retarded automatic unlocking of safety belts and harnesses of parachuting equipment or of vehicles, which comprises a frame slideably mounted in a casing and a shaft in the frame for supporting a swinging bolt adapted to imprison the shackle of a strap, or release either instantaneously under the direct action of a manual control means or with a delay under the action of an automatic control means connected to the bolt and actuated by springs compressed by the shackle when the shackle is introduced inside the casing. The automatic control means is itself locked by means adapted to be slowly withdrawn, by means of a brake, under the action of a traction force exerted by the shackle on the bolt providing the sliding movement of the frame against the action of a return spring bringing back the frame to its initial position as soon as the traction force of the shackle on the strap substantially diminishes or ceases.