Abstract: An apparatus for the thermal conversion of methane into hydrocarbons of higher molecular weight, comprising a reactor (1) of elongate form, connected on the one hand, at a first end, to an inlet for supplying gaseous mixture containing methane (process gas) and on the other, at the opposite end, to an outlet (10), the reactor comprising on the first end side a plurality of elements disposed in at least two layers disposed between two refractory walls, at least one refractory wall being disposed between the outside walls of the reactor, the layers being substantially parallel to the axis of the reactor, at least one of these layers comprising a series of sheaths (4) inside which there are electric heaters (3) which thus form a layer of heating elements, the elements being disposed in such a way as to define spaces or passages for the circulation of gaseous mixtures and/or effluents, the heaters and the sheaths being adapted to heat the said passages by successive independent cross-sections substantially at rig

Abstract: A flange (33) which can be connected to a length of pipe which is to be renewed (1a) and which comprises a series of separable disc-shaped elements individually constituted by a plurality of parts. Sealing-tight gaskets are interposed with a clamping effect between two element parts and between two adjacent disc-shaped elements. By way of a terminal flange element (33e) it is possible also to place at the end of the flange a monitoring device or a counter-flange (77) for guiding a casing pipe (35). The flange may be dismantled when casing is completed.

Abstract: The invention relates to a method for converting methane into higher hydrocarbons. According to the invention, a catalyst comprised essentially of a metal belonging to the series of transition metals and of a carrier which is comprised particularly of a refractory metal oxide is subjected to a methane flow at a temperature comprised between 100.degree. C. and 300.degree. C. approximately, with a contact time of at least one second, and to a hydrogen flow at a temperature comprised between 100.degree. C. and 300.degree. C. with a contact time of at least one second. The method of the invention is particularly usable in chemical engineering.

Abstract: The present invention concerns a non selective oxidation catalyst resistant to high temperatures and a method of preparation of this catalyst.According to the invention, this catalyst comprises an essentially alumina-based support stabilized with silicon and a precursor of the active phase consisting of a noble metal M in which the active phase is cationic amino-complex of the [M(NH.sub.3).sub.4 ].sup.++ type or a compound selected among the tetrachloropalladic acid.The catalyst of the invention is usable in particular in processes of catalytic combustion of hydrocarbons, of carbone monoxide, of hydrogen or of their mixtures.

Abstract: An interlaced meshed resistance network having one or more continuous wire conductors is formed from a tubular wire network cylinder folded over itself in order to have a double thickness into a flat annular ring shape. The resistance network can be used to bond heat fusing plastic tubes together. The wire is covered with a layer of material which is thermally conducting and electrically insulating up to a temperature about 300 to 350 degrees Celsius.

Abstract: A method of continuously modulating a fluid flow rate by means of an electrically controlled sequential valve, consisting in reciprocating the electrically controlled valve provided in a passageway conveying the fluid towards an apparatus to be fed therewith, between a position opening and a position closing said passageway, the frequency of the displacements towards either one of the valve positions being constant whereas the period of holding of the valve in the other position varies in accordance with the flow rate to be obtained, the method being applicable to the adjustement of the flow rate of a fluid such as a gas for a cooking apparatus for instance.

Abstract: A connecting device for connecting two thermoplastic pipes together including a thermoplastic body having a resistive element having a wire mesh structure and connection terminals. Each of the connection terminals has a tubular rivet body made of an electrically conductive material. The tubular rivet body includes a collar integrally formed with a hollow shaft and a flanged portion bent to immobilize the resistive mesh after the connection terminals are riveted to the mesh. This increases the reliability of the connection terminals to the resistive mesh.

Abstract: In a method of manufacturing a plastics material sleeve fitted with a heating wire and intended for producing an electric resistance welding connector the sleeve is molded to a cylindrical shape delimited by an outside surface and an inside surface; a helical groove is formed in one of these two surfaces of the sleeve; a wire is placed in the groove; and the plastics material heated by means of the wire is smoothed so as to cover the wire totally and close the groove. The electric resistance welding sleeve obtained in this way is in particular intended to be used either without overmolding it as an ordinary sleeve in particular for welding water pipes or after overmolding it as an electric resistance welding connector in particular for gas pipes.

Abstract: A portable device for straightening out pipes including a hollow beam provided at its two ends with first and second movable bearing members, respectively, one of which or first movable bearing member is actuated by a jack housed within the hollow beam whereas a grip for handling the device is transversely and adjustably mounted on the beam between the first and second movable bearing members and carries a third movable bearing member, the device being applicable in particular for straightening out polyethylene tubes to be assembled end to end.

Abstract: A method and apparatus for measuring the gaseous flow of a fluid flowing along a duct, the apparatus comprises a processing and control unit connected firstly to a flow rate measuring device which delivers data representative of the flow rate Qm of the gas under the conditions of temperature Tm and pressure Pm that are determined by temperature and pressure sensors disposed in said duct, and secondly to a unit for determining the compressibility factor Zm, which unit delivers data representative of the dielectric constant .epsilon. of the gas flowing in the duct, so as to enable the flow rate Q of the gas to be determined as reduced to predefined reference conditions of temperature To, pressure Po, and compressibility factor Zo. The data representative of the dielectric constant of the gas is obtained by a capacitive transducer constituted by a cylindrical capacitor placed under the same thermodynamic conditions as applied to the flow of gas.

Abstract: Burner fed with combustive air and combustible gas, comprising a distribution chamber (3) communicating with a combustion chamber (11), with interposition between them of a combustion grille (13). The distribution chamber is fed tangentially with air and gas and comprises a mixing turbine (15). The burner may be ignited through the periphery of the combustion chamber.

Abstract: A study is made of the changeover time of the voltage between an electrode and a metal work piece buried in the ground and protected against corrosion by an electric current. For this study, it is intended momentarily to interrupt the circulation of the protective current, to read the voltage between the work piece and the electrode, to pass these readings to an analog filter, to smooth these filtered signals by substituting them with values corresponding to a continuous and monotonic postulated function, and then to mathematically reconstruct the change in the voltage signals between the work piece and electrode such as it would be without filtering.

Abstract: Gas burner comprising a gas distribution chamber (3) fed with combustive air and combustible gas and communicating with a combustion chamber (15) through a main flame stabilization grille (11) having a lacunar structure, porous to the air/gas mixture. Preferably, the means (23) for ignition of the burner will be disposed outside the distribution chamber but will pass through the grille (11), the ignition being carried out either from one side of this grille, or from its periphery.

Abstract: The invention relates to an optical fibre including, over a part of its length, variations of refractive index disposed in plane, parallel and periodic strata, of period I, which are inclined at an angle .alpha. in relation to the axis of the fibre. The normal to the strata forms a non-zero angle with the axis of the fibre. The invention also relates to the application of the invention optical fibre as a selective extractor of flux, a light injector, a coupler, a sensor and a polarizer.

Abstract: The invention relates to a linear burner with jets extending through an opening made in a wall of a body of the burner defining an air-distribution chamber. According to the invention, the jets are connected to a series of tubes for supplying fuel gas or a gas/air mixture, these tubes passing through the body of the burner in order to be connected on the outside to a distribution housing provided with gas or with a gas/air mixture, this housing comprising adjustment means for selectively supplying the tubes joined to the jets.

Abstract: This is a system of fibre optic sensors comprising at least one such fibre for measuring a physical or chemical parameter sensitive to the change in an environment (E) within which the sensor is placed, the said fibre comprising a cladding (3), a core (5) surrounded by this cladding, an axis (7) with a length in the direction of this axis, and, locally along its parts (9) with variations in optical thickness forming an optical diffraction grating (10), at least one part of the cladding (3) comprising in its composition an active material whose optical properties vary as a function of the change in the said parameter (P) within the environment where the sensor is placed. The active material may be a heteropolysiloxane.

Abstract: A clamp comprising first and second pivotally connected jaws, each having an inner surface facing the other. According to the invention, in the closed position of the tool, the inner surfaces of the jaws, define between them, a crimping profile in the shape of an elongate "V"-shaped gap.

Abstract: The system comprises at least one combustion chamber, an expansion turbine, an air compressor driven by the expansion turbine, and means for coupling the expansion turbine to at least one external receiver of mechanical energy. The system further includes means for injecting water to constitute a thermal ballast in the combustion chamber, the quantity of compressed air used remaining close to the quantity of oxidizing air required for stoichiometric combustion.

Abstract: The invention relates to the conversion of saturated hydrocarbons.According to the invention a first gas containing chlorine and a second gas containing hydrogen are introduced into a chamber (3) so as to mix them. At the exit (4) of this chamber (3) the mixture of chlorine and hydrogen is ignited and the products originating from this flame are then mixed in a chamber (7) with a third gas containing the hydrocarbons to be converted, with a mean weight content of hydrogen element of at least 18%. The effluents from the chamber (7) are collected, quenched and fractionated. The hydrochloric acid is reformed into chlorine which is recycled in the first gas, the hydrogen is recycled in the second gas, and the alkanes in the third gas. The unsaturated hydrocarbons are recovered.The invention applies in particular to the conversion of natural gases into unsaturated hydrocarbons, such as ethylene.

Abstract: The installation comprises a selective liquid-feeder assembly, a selective gas-feeder assembly for feeding gas under pressure, a mixing and preheating assembly itself comprising a vaporizing stage, a mixing stage, and a preheating stage to raise the gas-vapor mixture to a temperature of about 150.degree. C. to about 300.degree. C., and a distributor assembly for distributing the flow of gas-vapor mixture to a plurality of high temperature generalized corrosion test circuits. Each test circuit comprises a reactor including an intermediate preheater stage for preheating the gas-vapor mixture applied to the reactor to a temperature of about 400.degree. C. to about 600.degree. C., and a final heater stage containing at least one sample of material to be tested which sample is put into contact with the gas-vapor mixture flow from the intermediate preheater stage, and raised in the final heater stage to a temperature lying between about 700.degree. C. and about 850.degree. C.