Abstract: The present invention relates to a method for determining mechanical parameters of a cementitious system, on the basis of time, and on the basis of the fineness of the cementitious system, pressure and/or temperature, representative of the in situ conditions found in wellbores. The initial composition of the cementitious system, the fineness ? thereof and the speed of the compression waves on the basis of time Vp(t) are the only input data of the method.

Abstract: The present invention relates to a method for determining mechanical parameters of a cementitious system, on the basis of time, and on the basis of the fineness of the cementitious system, pressure and/or temperature, representative of the in situ conditions found in wellbores. The initial composition of the cementitious system, the fineness ? thereof and the speed of the compression waves on the basis of time Vp(t) are the only input data of the method.

Abstract: The present invention provides improved well cementing methods for use in cold environment, where the circulating temperature of the cement is typically within the range of 5 to 20° C. The improved well cementing methods include forming compositions that are essentially comprised of an aqueous fluid, a hydraulic cement binder and a set-accelerating admixture comprising an alkali or alkaline earth metal nitrate and an alkali or alkaline earth metal nitrite.

Abstract: Method of well cementing with a foamed slurry having a very low water content. When based on ordinary cement, the solid fraction of the slurry includes (by volume) 20-35% Portland cement, 35-65% particles ranging from 200 ?m to 600 ?m, and 5% to 25% of fine particles in the range 0.5 ?m to 5 ?m and the water content is less than 50% by volume. When based on micro-cement, the solid fraction includes (by volume) 50-75% micro-cement, 15-40% fine particles in the range 0.5 ?m to 5 ?m, and 0-20% particles in the rang 3 nanometers to 60 nanometers and the water content is less than 72% by volume.

Abstract: A plugging fluid for plugging a subterranean formation zone surrounding a drill hole comprises an emulsion comprising a dispersed aqueous phase containing an aqueous base and a continuous hydrophobic phase containing a polymer consisting of a grafted cellulose ether derivative, a surfactant and a crosslinking activator of the polymer. The polymer is preferably 2-hydroxyethyl cellulose grafted with vinyl phosphonic acid. Upon shearing, preferably through the drilling bit, the emulsion inverts so that the rupture of the emulsion droplets releases the crosslinking activator into the water phase thus forming a gel structure.

Abstract: A plugging fluid for plugging a subterranean formation zone surrounding a drill hole comprises an emulsion comprising a dispersed aqueous phase containing an aqueous base and a continuous hydrophobic phase containing a polymer consisting of a grafted cellulose ether derivative, a surfactant and a crosslinking activator of the polymer. The polymer is preferably 2-hydroxyethyl cellulose grafted with vinyl phosphonic acid. Upon shearing, preferably through the drilling bit, the emulsion inverts so that the rupture of the emulsion droplets releases the crosslinking activator into the water phase thus forming a gel structure.

Abstract: A well cementing slurry, includes a solid fraction and a liquid fraction and has a density of less than about 1500 kg/m3. The solid fraction includes a mixture of solid particulate materials including cement, having 60% to 90% by volume of the solid fraction of a first component with particles having a mean size lying in the range 20 microns to 400 microns and a density of less than 2000 kg/m3; and 10% to 30% by volume of the solid fraction of a second component having a mean particle diameter of less than 5 microns.

Abstract: The invention relates to a cement slurry for cementing an oil well or the like, the slurry having a density lying in the range 0.9 g/cm3 to 1.3 g/cm3, and being constituted by a solid fraction and a liquid fraction, having porosity (volume ratio of liquid fraction over solid fraction) lying in the range 38% to 50%. The solid fraction is constitued by a mixture of lightweight particles, microcement and optionally portland cement and gypsum. Such cements have remarkable mechanical properties due to their very low porosity in spite of having very low density.

Abstract: The present invention provides improved well cementing compositions for use in cold environment, where the circulating temperature of the cement is typically within the range of 5 to 20° C. The improved well cementing compositions are essentially comprised of an aqueous fluid, a hydraulic cement binder and a set-accelerating admixture comprising an alkali or alkaline earth metal nitrate and an alkali or alkaline earth metal nitrite.

Abstract: A remote handling device includes a master arm and a slave arm adapted to reproduce the movements of the master arm. The slave arm is located within a confinement chamber. The master arm is located outside the confinement chamber. The master and slave arms are interconnected by a mechanism passing through a wall of the confinement chamber. The master arm is connected by a connection tube to the mechanism. The master arm and the connection tube are connected to coupling and uncoupling means adapted to permit their modular connection or disconnection.

Abstract: The invention relates to a method of gasifying carbon-containing compounds incorporating mineral elements and/or potential contaminants, and it also relates to a gasification installation having means for containing a bath of molten slag, means for charging said compounds into said bath, means for injecting at least oxidizer into the bath so that the mixture of carbon-containing compounds and oxidizer is super-stoichiometric, whereby a first fraction of the compounds is pyrolyzed, a second fraction is subjected to a combustion reaction suitable for delivering heat energy to the bath of slag, and a third fraction diffuses into the bath, means for recovering the gas given off by the pyrolysis and the combustion of the first and second fractions, and means for lowering the temperature of a portion of the molten slag so as to allow it to solidify, thereby immobilizing at least a portion of the third fraction of the compounds containing mineral elements and/or potential contaminants.

Abstract: A plugging fluid for plugging a subterranean formation zone surrounding a drill hole comprises an emulsion comprising a dispersed aqueous phase containing an aqueous base and a continuous hydrophobic phase containing a polymer consisting of a grafted cellulose ether derivative, a surfactant and a crosslinking activator of the polymer. The polymer is preferably 2-hydroxyethyl cellulose grafted with vinyl phosphonic acid. Upon shearing, preferably through the drilling bit, the emulsion inverts so that the rupture of the emulsion droplets releases the crosslinking activator into the water phase thus forming a gel structure.

Abstract: A plugging fluid for plugging a subterranean formation zone surrounding a drill hole comprises an emulsion comprising a dispersed aqueous phase containing an aqueous base and a continuous hydrophobic phase containing a polymer consisting of a grafted cellulose ether derivative, a surfactant and a crosslinking activator of the polymer. The polymer is preferably 2-hydroxyethyl cellulose grafted with vinyl phosphonic acid. Upon shearing, preferably through the drilling bit, the emulsion inverts so that the rupture of the emulsion droplets releases the crosslinking activator into the water phase thus forming a gel structure.

Abstract: The invention concerns cementing compositions, particularly for squeeze cementing, comprising a liquid phase and a solid phase constituted by particulate materials which are insoluble in said liquid phase, in particular a microcement. The compositions of the invention comprise additives of a nature and composition such that variations in viscosity of the composition due to fluid loss are minimized. Preferably, the compositions comprise at least one “very fine” additive formed from particles which are smaller than the cement, with a ratio of the average grain sizes of the particles of said additive and those of the cement in the range 5 to 100, preferably about 10, the respective proportions of the solid particles corresponding to a packing volume fraction close to the maximum, and the porosity of the solid mixture being such that the mixture is in a state of hindered settling.

Abstract: A load lifting device of the hoist type, comprises a flat strip 5 arranged to form two hoist runs on opposite sides of a connection member 6 for a load. The two runs of the strip 5 are simultaneously wound up on, or unrolled from, a single reel. A spacing roller 20 forms in the strip 5 a substantially horizontal upper run. This improves the stability of the load by spacing apart the upright runs 21, 22 of the hoist.

Abstract: So as to avoid installing a heavy remote handling machine in a containment comprising a lifting unit, such as a travelling crane, the present invention proposes an autonomous remote handling machine (20) suitable for being suspended from the hook (b 16) of this crane. This machine (20) includes a support (22), a gripping arm (24) and a counterweight (26) being joined to said support around a normally horizontal axis (26). A device (44) detects any possible slanting of the support (22) with respect to vertical in order to control any modification of the orientation of the counterweight (26), independently of the orientation of the arm, so as to annul any detected slanting.

Abstract: A method for fixing a tube by expansion improve the seal between a tube and a support plate which are joined by expansion fixing. The method comprises forming fine annular projections on the surface of a bore which is formed in the support plates, and inserting a tube within the bore so that upon expanding the tube within the bore, the projections engage the tube to produce a seal.

Abstract: A gas-tight connector, especially for the remote handling of radioactive or hazardous products by means of a master-slave manipulator. The connector is composed of a tong-unit connector element, a gas-tight connector element and a remote-manipulator connector element. The gas-tight element is engaged coaxially within the tong-unit element and the remote-manipulator element is engaged coaxially within the gas-tight element and also coupled to an articulated supporting arm. All three elements are traversed from one end to the other by shafts which are capable of translational motion in order to initiate opening and closing of the tong unit.