Abstract: A rigid redundant light source for obtaining down hole near infrared data in a NIR data acquisition instrument is provided having a plurality of lamps positioned in close proximity and symmetrically about a common optical axis. A lens system for capturing and collimating the light is provided. The structure is arranged and dimensioned so that a single collimating lens can be used for a plurality of light sources. A switch and sensor is provided for turning on an alternate light source when a first light source burns out. A filter is rotated 90 degrees with respect to the light sources to minimized off axis error when switching between light sources.

Abstract: A rigid redundant light source for obtaining down hole near infrared data in a NIR data acquisition instrument is provided having a plurality of lamps positioned in close proximity and symmetrically about a common optical axis. A lens system for capturing and collimating the light is provided. The structure is arranged and dimensioned so that a single collimating lens can be used for a plurality of light sources. A switch and sensor is provided for turning on an alternate light source when a first light source burns out. A filter is rotated 90 degrees with respect to the light sources to minimized off axis error when switching between light sources.

Abstract: A magnetic coupling for substantially synchronously transferring linear motion through a non magnetic barrier from a first movable element to a second movable element. The coupling comprises magnets disposed at spaced apart locations along the first element. The magnets each have a magnetization direction substantially perpendicular to a direction of motion of the first element along the non magnetic barrier. The coupling includes magnets disposed at spaced apart locations along the second element at locations corresponding to locations of the magnets op the first element. Each of the magnets on the second element has a magnetization direction inclined at an oblique angle with respect to the magnetization direction of the corresponding magnet so as to capture magnetic flux from the magnets on the first element when either of the elements is moved along the barrier.

Abstract: A well logging instrument string including a first section adapted to be operated substantially in contact with a wall of a wellbore, a coupling connected at one end to one end of the first section. The coupling includes first and second flexible joints for enabling relative angular deflection between the first section and a second section. The coupling includes a biasing mechanism for urging at least one of either the first or the second flexible joints, or both, to assume their positions of maximum angular deflection. The instrument string includes a second section connected to the other end of the coupling. The second section is adapted to be operated spaced apart from the wellbore wall.

Abstract: A cable head connector is provided for coupling a plurality of nested tubes, each one of which conducts a different fluid, to a downhole geophysical tool such as a seismic sound source. The device includes separate clamps for individually gripping the respective nested tubes. Conduits are furnished for fluidly bypassing the respective clamping devices. The fluid bypass conduits are fluidly coupled to a distribution module for delivering the different fluids individually to the downhole geophysical tool. Additional facilities are provided for sending electrical control signals to the tool.

Abstract: Method and apparatus for nondestructive inspection of oilfield piping includes first and second elongated nonmagnetic housing members having an elongated magnetic core therebetween. A first coil assembly for emitting a unidirectional flux field is coupled to the core member. Detector shoes are coupled to said core member proximate the first coil assembly and are based into contact with the interior surface of the piping. Second and third coil assemblies are coupled to the core member for emitting unidirectional fields in opposition to the field emitted from the first coil assembly.

Abstract: Apparatus for indicating the location of casing joints or collars in a cased borehole utilizing a magnetic field. An electrical detector coil array is disposed within an elongated body member having a plurality of arm member equidistant thereabout. Each arm member carries a casing contact pad having a permanent magnet mounted therein. The expansion force exerted on the arm members and the maximum range of expansion are independently adjustable.

Abstract: A method is provided for determining the natural current flow in the casing of a well. The method includes measuring the native voltage between two locations in the casing during natural current flow conditions. A known electrical current is then passed through the well casing and the voltage between the two locations is measured again. The casing resistance between the two locations is then determined from the voltage measurements and known electrical current. The native current flow in the casing is then determined from the native voltage measurement and the casing resistance.

Abstract: An apparatus for determining the natural current flow in the casing of a well. The apparatus includes earth surface control and recording equipment connected by a cable to an instrument housing. A casing collar locator on the instrument is used to assist in positioning the instrument in the well casing. A plurality of electrodes on the instrument are contactable with the interior of the casing. The earth surface equipment and the electrodes are used to measure voltages and to pass an electrical current through the casing. Measurements of native voltages in the casing and the change in voltage between two locations in the casing during application of a known current are used to determine the casing's resistance at that location in the well and the native current flow between the well casing and the earth formation throughout the well.

Abstract: Apparatus is provided for assisting a subsurface well logging instrument, perforating tool or wireline service tool in tubing or casing re-entry in deviated boreholes. The apparatus includes a body member, composed of two conjugated halves, rotatably mounted on the well logging cable immediately above the well logging instrument. A pair of wheels are rotatably mounted to the uphole facing portion of the apparatus. These wheel members provide a lifting action upon tubing or casing contact to thereby lift the logging cable off the casing and prevent the logging instrument from engaging in jammed contact with the exposed end of the tubing or casing.

Abstract: A system for orienting a well casing perforating gun for utilization in wells having multiple tubing strings wherein it is desired to perforate the well casing in a zone other than the deepest production zone of the well and includes a hoist and associated apparatus for moving the perforating apparatus through the well and actuating the perforating gun. The perforating apparatus includes an elongated housing supportable on a cable, rollers on the exterior of the housing to support it on the interior of the well casing and/or tubing, the casing perforating gun, an orienting apparatus operable to orient the perforating gun relative to a string of tubing within the casing, a swivel within the housing to permit rotating motion of the lower portion of the housing relative to an upper portion of the housing, and an eccentric weight below the swivel to assist in positioning and aligning the casing perforating gun to the desired position.

Abstract: Electronics circuitry for obtaining measurements of subsurface formation parameters is mounted on an elongated chassis which is removably disposed within a tubular housing. One or more sets of angularly disposed ball rollers are disposed along the length of the chassis. At least one of the ball rollers comprising each set will be of the plunger type, capable of exerting a high force level due to the preloaded compression of a plurality of disk springs. The ball rollers are angularly disposed and operatively set so as to exert restraining force upon the chassis while allowing simple insertion into the housing.