Abstract: A method and apparatus for detecting and measuring gelled material (i.e. gelled pig) as it passes through a tubular by generating ultrasonic pulses at timed intervals which, in turn, are transmitted through said tubular and materials flowing therethrough at a fixed point along said tubular. These pulses are received after they have passed through said tubular and the materials and are processed to identify those pulses which travel through said gelled material as said gelled material passes by said fixed point. From the number of identified pulses, the length of the gelled pig can be determined.

Abstract: A coiled tubing injection unit for injecting a continuous length of coiled steel tubing into a wellbore for performing well operations includes an x-ray inspection apparatus arranged to continuously monitor the wall section of the tubing as it is inserted into or withdrawn from the well to detect structural defects in the tubing. An x-ray source and detector unit are mounted in a housing which is supported for rotation about the longitudinal axis of the tubing for projecting an x-ray image through suitable processing and display apparatus. The x-ray detection unit may be mounted on a level wind mechanism of the coiled tubing storgage spool or at another point between the storage spool and the wellhead into which the tubing is being injected.

Abstract: Wellbore fluid flow rates and other fluid properties may be measured by a tool which is insertable in the wellbore on the end of a tubing string and includes an instrument section and an inflatable packer disposed on the tool for inflation by conducting pressure fluid down the tubing string to the packer. A control valve disposed on the tool is hydraulically shiftable between first and second positions for conducting fluid from the tubing string to the packer and from the packer to the exterior of the tool. The valve may be actuated by fluid conducted down the tubing string. The tool includes housing parts having respective cavities for conducting wellbore fluid through a flowmeter and for containing instrument circuit enclosures disposed therein. Pressure fluid bypasses the cavities through elongated passages formed in the tool housing parts along or adjacent to the outer periphery of the housing parts. A frangible coupling is interposed in the tool between the packer and the instrument section.

Abstract: A fluid flow measuring or so-called production logging instrument for fluids produced in a well includes an inflatable packer for forming a seal in the wellbore to require diversion of wellbore fluid through a passage formed in the instrument whereby fluid flow rate and other fluid properties may be measured. The inflatable packer receives pressure fluid from the tubing string and may be remotely controlled to inflate and deflate, at will, through signals conducted from the surface to the instrument by way of a cable extending through the tubing string. The instrument includes a main wellbore fluid flow passage in which a shutoff valve is disposed for controlling the flow of fluid through the passage and which may be automatically closed or opened in response to actuation of the packer seal.

Abstract: A swivel connector for interconnecting a wireline cable with a logging tool includes an elongated tubular body member having a cavity for supporting one or more slipring assemblies. An elongated shaft is disposed partially in said body member and extends from a lower end thereof and is supported on rolling element bearings. The shaft is connected to the rotors of the slipring assemblies while the stator members of the slipring assemblies are held stationary in relation to the body member by an elongated axial key. Flexible electrical conductors from the wireline cable are connected to the stator and flexible conductors are connected to the slipring rotors and extend through an axial passage in the shaft toward a plug for connecting the conductors to the logging tool.

Abstract: A latching tool for retrieving downhole well instruments and devices is adapted to be connected to the lower end of a tubing string for movement for movement to engage a fishing head connected to the instrument or device to be retrieved from the wellbore. The latching tool includes a body made up of separable members and having a through bore formed therein, plural radially movable spring biased latching dogs, and an elongated sleeve disposed for sliding movement in said bore for holding said latching dogs in a retracted position and permitting said latching dogs to move to an extended and latching position in response to movement of the sleeve.

Abstract: Multiple downhole seismic signals are generated by an apparatus comprising one or more elongated rod segments insertable in a borehole and provide with spaced-apart predetermined lengths of Primacord explosive charge helically wrapped on the exterior of the rod segment and spaced apart by circumferential baffles supported on the rod segment. The charges are selectively fired through a motor actuated selector switch and a switch stepping and firing circuit including only two conductors and blocking diodes for imposing signals of opposite polarity on the selector switch and its actuating motor.

Abstract: Apparatus for interconnecting a tubing string with downhole tool and for controlling the flow of fluid into a wellbore through the tubing string comprising an elongated body member and a resiliently deformable sleeve disposed around the body member and radially deformable to form a seal against the wellbore wall to seal off a zone of interest. The body member includes a passage for extension of a wireline cable from the tubing string to the downhole tool. An electric motor operated rotary plug valve is disposed in the apparatus body and is operable to be rotated to valve pressure fluid from the tubing string into an expansible chamber to cause the seal sleeve to deform to seal the wellbore. The valve member is movable to positions to relieve pressure fluid from the seal, to valve pressure fluid to the wellbore at an injection point below the seal and to block all ports.

Abstract: A connector for attaching a downhole tool to the end of a tubing string insertable in a wellbore includes a one-way valve to permit flow of fluids from the tubing string into the wellbore but to prevent the flow of fluids in the opposite direction. An electrical cable extends through central passages formed in the one-way valve and a frangible coupling which will separate the connector from the tool if the tool becomes stuck in the wellbore.

Abstract: A modular connector for interconnecting a coilable tubing string with a downhole electrical tool and wherein an electric signal conducting cable extends through the tubing string and through the connector. The connector includes a swivel coupling having a coupling body with a spherical socket for receiving a spherical coupling member which is connectable to the downhole tool through a cable connector body secured to the spherical coupling member. A pin disposed in the coupling body projects into a slot in the spherical coupling member to prevent rotation of the tool with respect to the longitudinal central axes of the connector and the tool. The connector includes a frangible coupling for retrieving the tubing string if the downhole tool becomes stuck. Separation of the frangible coupling exposes a fishing head for retrieving the tool.

Abstract: A connector for attaching a downhole tool to the end of a tubing string insertable in a wellbore includes a frangible coupling portion having a pin with a predetermined cross sectional area which will fail in tension to separate the connector from the tool if the tool becomes stuck in the wellbore. The pin is disposed in a body member of the connector and interconnected therewith by spring washers to absorb transient shock or impact loads on the tool. The connector includes passages for extending electrical conductors through the coupling portion whereby electrical signals may be transmitted through the tubing string to the downhole tool.

Abstract: A downhole tool is supported by coilable tubing extending into the wellbore from a tubing injection and withdrawal apparatus and includes an elongated electrical signal transmitting cable extending through the tube between the tool and the injection apparatus. The tool is connected to one end of the tube by a connector assembly which provides for limited swiveling movement of the tool relative to the end of the tube to preclude excessive lateral loads from being exerted on the tool during positioning of the tool in the wellbore. The connector assembly includes a frangible coupling comprising coupling members which are interconnected by shearable pins whereby separation from the tool will occur at the connector assembly in the event the tool becomes stuck in the wellbore. One of the coupling members includes a fishing neck for engagement with a suitable fishing tool whereby the downhole tool may be retrieved if separated from the tubing.