Abstract: A pig for the removal of ferromagnetic debris from the internal surface of a pipeline comprises a plurality of large area pole pieces of hard ferromagnetic material mounted on low reluctance spacers so that the spacing of poles of opposite polarity is approximately equal to the spacing of the pole pieces from the nominal position of the internal surface of the pipeline.

Abstract: An automatic arrangement in which the intermittent tapping of liquid molten slag from the hearth of a slagging coal gasifier vessel (30) through a tap orifice (32) into a slag quench chamber (31) is selectively controlled by a system of timers (T1, T2, T3), the differential pressure between the gasifier vessel (30) and the quench chamber (31) being measured (22) and deviations from the expected measurements caused by malfunctions being used to override the timer system until the malfunctions have been corrected.

Abstract: In one method of non-destructive inspection of bodies of ferromagnetic material such as buried or submerged pipelines, probes containing magnetic sensors scan the surface of the body to detect flaws as local variations in the magnetic field. Such sensors are sensitive to changes in velocity of the probe carrier which manifests itself in variations of output signal amplitude. Such variations are eliminated by matching the sensor with a correction circuit having complementary frequency response characteristics.This technique may be used in conjunction with a threshold circuit to eliminate unwanted data.

Abstract: In electronic discrimination circuitry each of a plurality of at least three analog input signals is converted to respective digital pulse output signals and to a number of multi-phase clocking signals equal in number to the plurality of input signals are also generated such that each of the plurality of at least three analog input signals is synchronized in response to a respective one of the multi-phase clocking signals, whereby at least the leading edge of each of the digital output signals is positioned into a time slot corresponding to the multi-phase clocking signals. Selected pairs of the synchronized digital output signals are sequentially compared to determine within each compared pair that digital output signal having a higher frequency and comparing that digital output signal with another digital output signal until the digital output signal having the highest frequency is selected.

Abstract: Liquefiable gases such as associated natural gas may be liquified, stored in the liquid form and re-vaporized by cooling a pressurized first liquified gas stream by indirect heat exchange with a first stream of a refrigerant, such as liquid nitrogen, to form a second liquified gas stream whose temperature is less than its initial boiling point at ambient pressure and a first warmed refrigerant stream. The second liquified gas stream is passed to a vessel wherein the liquified gas is stored. When the gas is required the second liquified gas is removed from the storage vessel and warmed by indirect heat with a second warmed refrigerant stream, to form a third liquified gas stream and said first refrigerant stream. The warmed refrigerant stream is also in indirect heat exchange with said first warmed refrigerant stream and after heating comprises second warmed refrigerant stream. Thereafter, the third liquified gas stream is vaporized.

Abstract: A regulator installation, for controlling the pressure and/or flow of gas in a gas transmission or distribution system, comprising a compact module (10) having an inlet (32) and an outlet (33) adapted to be fitted in a pipeline (1) and containing within its outer shell (21,22,23) a removable assembly secured by locking means (29,30) and which carries the essential elements (2 to 9 and 43 to 45) of the regulator installation such that the gas flow path from the inlet (32) passes through the elements (2 to 5) to the outlet (33). The shell is provided with a removable cover (23) for gaining access to the control elements (6 to 9 and 43 to 45) and to the locking means (30) for enabling the assembly (31) to be removed for servicing and replacement.FIG. 2 is suggested as the drawing to accompany the Abstract.

Abstract: A magnetic coupling member for a magnet assembly of a pipeline inspection vehicle comprising one or more stacks of foils arranged as multi-layer laminations interleaved with short spacers and clamped together between clamping blocks by bolts. The assembly of clamped-together stack of foils is secured to the magnet of the vehicle magnet assembly by removable bolts which enable easy replacement of worn or damaged stacks of foils.

Abstract: A wheel probe for ultrasonically inspecting a component, such as the wall of a pipe, is of hollow form to define a chamber in which at least one ultrasonic transducer is supported to direct and receive ultra-sound through the wheel probe. The chamber is filled with an acoustic coupling liquid, and at least one resilient diaphragm is provided in the wall of the chamber so as to deflect in response to a difference in pressure thereon and balance the pressure of the liquid with that of the environment about the wheel probe.

Abstract: Hydrocarbon oils, particularly oils which have a high boiling temperature, are treated to remove organic sulphur compounds by subjecting a mixture of a hydrogenating gas, e.g. a gas containing at least 90% v/v hydrogen and is substantially free from carbon oxides, and partially vaporized oil to a hydrogenation reaction over a known hydrogenation catalyst and thereafter passing the resulting liquid/vapor mixture which also contains hydrogen sulphide over zinc oxide, thereby to remove the hydrogen sulphide.

Abstract: A method of detection of inaccessible metallic objects such as gas, electricity, water or telecommunications systems (lines) through which an alternating current is flowing, comprises making at least three spatially separated measurements of the magnetic field associated with the current. Signals derived from the measurements are compared in a detector which gives an output indication when the signals derived from the measurements at the two outer locations are equal and each less than the signal derived from the measurement at the intermediate location.A suitable sensing device has four equally spaced pickup coils and operates at a frequency of 43KHz. The alternating current detected in the metallic objects may be induced by a separate transmitter.

Abstract: A method for connecting a plastics pipe to a fitting incorporating an externally grooved insert. The insert, which is a tight fit in the pipe, is forced into the end of the pipe, and a sleeve, previously located on the pipe, is then forced to the end of the pipe so that the pipe end is tightly gripped between the insert and the sleeve. The insert is tubular and is provided with a plurality of circumferential grooves in its outer surface. Each groove has in axial section substantially straight sides and a straight base, the angle between the base and each side being obtuse. Insertion of the insert causes the external diameter of the pipe to increase so as to be greater than the internal diameter of the sleeve.

Abstract: A pipe inspection device for ultrasonically inspecting the wall of a pipe includes a support arm which is pivotally attached at one end to an inspection vehicle and at its other end pivotally supports a spindle at the end of which two wheels are rotatably mounted. One or more ultrasonic transducers are disposed inside each wheel so that when the vehicle is moved along the pipe, the wheels come into contact with the pipe such that the transducers are aligned in predetermined positions relative to the pipe. The device may be arranged for insertion in the bore of the pipe, or for assembly around the outside of the pipe.

Abstract: A pipe inspection apparatus includes a vehicle which is capable of moving along the bore of the pipe, two rubber cup-shaped members at each end of the vehicle for aligning the vehicle lengthwise in the pipe, a floating assembly of inspection devices such as ultrasonic transducers disposed circumferentially around the vehicle, and at least four link members pivotally attached to the assembly and to the vehicle to constrain the assembly to move in a direction normal to the length of the vehicle. The assembly may be resiliently suspended from the vehicle, and may also be provided with a centralizing device, such as a rubber cup-shaped member or rollers or skids, to centralize the assembly in the bore of the pipe.

Abstract: Methane-containing gases are produced by the catalytic-stream-reforming of hydrocarbon feedstocks using a catalyst which includes a Group VIII metal such as nickel and alumina, and which in its calcined but unreduced precursor form has a pore size distribution defined as follows:(i) at least 55% of the pore volume of pores having a pore radius between 12 and 120 Angstrom Units is in the range of 12-30 Angstrom Units, and(ii) the ratio of the pore volume contained in pores of 10-50 A to the pore volume contained in pores 50-300 A is at least 5:1.

Abstract: An improved slag outlet for a slagging gasifier, comprises a cast body of high thermal conductivity having integral coolant passageways, said passageways being formed by shaping a metal tube into a coil having an inlet and an outlet, and casting metal to the desired shape around the coil such that the inlet and outlet communicate exteriorly of the cast body.

Abstract: A catalyst precursor which when reduced can produce a catalyst suitable for the high pressure gasification of heavy hydrocarbons to produce methane-containing gases comprises a calcined coprecipitated-alumina containing from 50-65% Ni precursor. The catalyst contains (1) from 0 to not more than 0.43% K and from 0 to not more than 0.1% Na, (2) the combined weights of Na+K does not exceed 0.011 gm atoms/100 gm of catalyst, precursor (3) the ratio of Na: K falls within the area defined by ABCDEO in FIG. 1 of the drawings and (3) at combined Na+K weights of from 0 to 0.05% the water loss is not more than 11.2%.The catalyst precursors are prepared with the aid of a filtering aid selected from (NH.sub.4).sub.2 CO.sub.3, Na.sub.2 CO.sub.3, K.sub.2 CO.sub.3, Na NO.sub.3 or K NO.sub.3 to obtain low levels of alkali. The final catalyst may be employed for steam reforming reactions to produce methane-containing gases.

Abstract: Steam reforming catalyst having good sinter and polymer resistance and which include a Group VIII metal such as nickel and alumina, have in their calcined but unreduced precursor form pore size distributions defined in the following relationships:(i) at least 55% of the pore volume of pores having a pore radius between 12 and 120 Angstrom Units is in the range 12-30 Angstrom Units, and(ii) the ratio of the pore volume contained in pores of 10-50 A to the pore volume contained in pores of 50-300 A is at least 5:1.These catalysts are prepared by coprecipitation at temperatures of not greater than 60.degree. C. wherein a solution of an alkali precipitating agent is added to a solution of the catalytic components.

Abstract: A process, having high thermal efficiency, is provided for the production of substitute natural gas from fossil fuels such as crude oil, by non-catalytic hydrogenation. High thermal efficiency is obtained by using cryogenic systems for separating hydrogen from (a) the product of the hydrogenation reaction and (b) from products produced by partial oxidation in the production of hydrogen required for the hydrogenation reactions. Other products from the partial oxidation reaction may be used either as fuel or as feedstocks for catalytic steam reforming to produce SNG.

Abstract: Disclosed is a wheel probe for use on a pipe inspection vehicle. The wheel probe comprises a annular perspex outer rim with a polyurethane tire mounted on a hub assembly which, with the hub, defines a fluid-tight chamber containing an acoustic coupling fluid. A number of ultrasonic transducers are located inside the chamber and are positioned close to the inside circumferential surface of the rim. The hub assembly is carried by a spring loaded carriage which is secured through which ultrasound will pass.The wheel probe includes a guide wheel on each side. The guide wheels are carried by the carriage but are moveable bodily relative to the center of the hub assembly, and when deflected, they operate on the assembly to move the wheel probe to ensure that the outer rim of the wheel is correctly aligned relative to the pipe.The wheel probe has a number of shields spaced around its periphery.

Abstract: A coal slagging gasifier and method of operating such gasifier are improved by providing an improved slag removal orifice. The orifice is located centrally within the hearth of a gasifier of the type in which hot burner gases are directed up through the orifice to retain the slag in molten condition on the hearth and in which the slag is periodically discharged through the slag removal orifice. The slag removal orifice is formed as a substantially vertical passageway through the removable slag tap member which comprises a solid cast mass of high thermal conductivity metal having an integrally formed metal tube for circulating liquid coolant through the cast mass. The upper tundish surface of the slag tap member slopes downwardly and inwardly and merges with the slag removal orifice.