An engine fuel flow shut-off system particularly adapted for off-highway dumper trucks includes a shutoff valve interposed in the fuel supply conduit to the truck propulsion engine and which is responsive to a pressure fluid control circuit to close. Compressed gas charge bottles operable from the operator's cab and from a ground position in proximity to the vehicle boarding ladder supply pressure fluid to the valve actuator to provide closure of the valve and closure of a second valve to interr...

Crude oil sludges and other relatively heavy hydrocarbon liquid sludges are mixed with diatomaceous earth or perlite to form a friable and flowable solids mixture which is conveyed to a combustion unit, such as rotary kiln, calciner or lift pipe type combustor, wherein combustion of the hydrocarbons is carried out to provide gaseous combustion products and a substantially hydrocarbon free solids mixture. The solids discharged from the combustion unit may be recycled for use in the mixing process...

Seismic measurements are taken during drilling operations by an array of seismometers placed on the earth's surface about the axis of a drillstring connected to a conventional drillbit and wherein the drillstring has an arrangement of strain gages and accelerometers mounted thereon in such a way as to measure axial and torsional vibrations of the drillstring. Signals indicating vibrations induced by the drillbit or another source and transmitted through the drillstring are compared with signals ...

Magnetic field sensing circuits including wire coils and Hall effect devices are provided which produce high-gain output for a relatively low change in perceived field intensity. Series connected plural Hall effect devices are connected to the coil and include amplifier and integrator circuits interposed at selected points between Hall effect devices to modify the output signal gain and passband. The circuits may include diode and capacitance elements to modify the circuit output signal.

Ion chromatograms are prepared with a chromatograph including a separation column and a conductivity measuring ion detection unit which are adapted to be selectively placed in communication with separate reservoirs for diluted and undiluted samples of a fluid to be analyzed. A control unit switches the reservoirs into communication with an eluent pump for displacing fluid samples through the detection unit in timed relationship such that the most concentrated ion is measured in the diluted sampl...

Hydrocarbon gas, such as methane, is partially oxidized by flowing the gas through a moving catalyst bed supported on a rotating drum disposed in a partitioned duct. Catalyst is regenerated by exposure to an oxygen containing gas flowing through a passage formed in the duct. A gas seal is formed between the duct partition and a surface of the catalyst support drum on the downstream side of the drum to minimize the leakage flow of hydrocarbon gas into the regenerator gas. The pressures of the hyd...

Downhole conditions in wellbores such as fluid pressure, temperature and flow conditions during drillstem testing or during wellbore stimulation or fracturing processes are transmitted through sensing and signal conversion circuits to axial or torsional wave vibrators secured to a drillstem or tubing string in the borehole for generating stress wave vibrations in the drillstem or tubing string for transmission to a point at or near the earth's surface. Accelerometers and/or strain gauges are mou...

The shear velocity of a region of an earth formation may be determined by a logging tool insertable in a wellbore penetrating the formation which includes plural transducers for generating compressional waves for transmission through the formation as shear wave between the signal generating transducers and an array of signal receiving transducers spaced from the signal generating transducers. The transducers may be plural in number and arranged to effect impingement of the compressional wave on ...

A continuous mining apparatus such as a coal milling or shearing machine includes sensors mounted on the machine frame or on the cutter bits, including an accelerometer and one or more strain gauges, for sensing vibrations and stresses exerted on the cutter bits during operation of the machine. A signal conditioning and amplification circuit provides an audio and/or visual display indicating when the cutter is moving outside of the coal seam and/or is cutting along a cleat or other joint to impr...

A freestanding offshore well structure includes a generally cylindrical caisson having a relatively small diameter drivepipe section connected to a larger diameter caisson section which is of sufficient strength to withstand wind and wave action. An upper portion of the drivepipe section is provided with a landing ring for a hanger for a conductor casing string or a wellhead body for a surface pipe string. A casing connector or nipple supports a diverter above the landing ring. The caisson is dr...