Abstract: A novel hydraulic set packer is set independently of the setting of two other straddle packers, the straddle packers being set by other than hydraulic means, such as by inflation or compression. If the straddle packers are set by inflation, a novel inflate deflate valve is associated with both straddle packers for providing an additional method to deflate the inflatably set straddle packer. If the straddle packers are compression set, it may be necessary to allow a top staddle packer to set only after the bottom straddle packer is already set, that is, the top straddle packer is not permitted to set when the straddle packer assembly is being pushed into a deviated/horizontal borehole or through a restriction in the borehole. Accordingly, a novel hydraulic ratchet, disposed above a bottom straddle packer on a tubing but below the top straddle packer on the tubing, will enable the top straddle packer to set only after the bottom straddle packer is already set.

Abstract: A perforating gun having no firing head and no primary explosives is attached to a tubing string and the tubing string is run into a borehole. A new pump apparatus, having a firing head, is run into the tubing string until the pump firing head is adjacent the perforating gun. The firing head in the pump apparatus detonates, firing the perforating gun. If the firing head fails to detonate, one need only remove the pump apparatus from the tubing string in order to gain access to the firing head, for repair and replacement thereof. One need not remove the tubing string to gain access to the firing head.

Abstract: A well logging system includes a digital threshold crossing data generation system (TCDG System) disposed in a well tool, adapted to be disposed in a borehole, and a digital first motion detection (DFMD) software disposed in a memory of a well truck computer. The TCDG system generates a series of threshold crossings for each analog signal received from a receiver of the well tool, the threshold crossings including a plurality of threshold crossing events for each analog signal and representing compressed versions of digitized analog waveforms. The well logging truck computer receives the threshold crossing data from the TCDG system and executes the DFMD software. When the software is executed, a first set of compressional wave first arrival times are determined from a startup routine in the software using the threshold crossing data.

Abstract: A logging tool for measuring the fluid flow rate in a well, comprises a measuring pipe provided with a flowmeter, a packer device designed to derive the whole fluid flow into the measuring pipe, and an obstacle disposed in the fluid flow path, at, or downstream of, the exit of the packer for increasing, through the fluid flow action, the pressure of the fluid located upstream of the packer. The obstacle is e.g. a valve responsive to flowing fluid pressure on one side and to a biasing spring on the other side. The packer includes, in its bottom end designed to seal with the casing wall, an anulus seal defining a tubular chamber able to be inflated under the sole fluid action the annulus seal being made by two circumferential parts, facing one another, and fixed along their upper and lower perimeters. The tubular chamber is in communication with the fluid flow and is adapted to expand radially upon the application of fluid pressure while being substantially longitudinally non-extensible.

Abstract: The invention relates to an electrical connector for transmitting electrical signals between the outside and the inside of a well having a well head (20) terminated by a valve assembly (10). The connector comprises at least two inductively coupled electrical coils (1A, 1B; 5A, 5B) whose respective winding axes are aligned with the axis (zz') of the well head. The coils are integrated in the fluid connector interconnecting the valve assembly and the well head, with one of the coils being releasably fixed to the valve assembly (10) while the other coil is releasably fixed to the well head (20).

Abstract: A perforating gun having no firing head and no primary explosives is attached to a tubing string and the tubing string is run into a borehole. A new pump apparatus, having a firing head, is run into the tubing string until the pump firing head is adjacent the perforating gun. The firing head in the pump apparatus detonates, firing the perforating gun. If the firing head fails to detonate, one need only remove the pump apparatus from the tubing string in order to gain access to the firing head, for repair and replacement thereof. One need not remove the tubing string to gain access to the firing head.

Abstract: An input stimulus provides a necessary input to a microprocessor implemented control system. The control system may fire one or more perforating guns of a perforating apparatus or it may change the state of a valve in a well testing apparatus. The input stimuli may comprise a pressure pulse transmitted down a well annulus disposed between a tubing string and a borehole casing, a pressure pulse transmitted internally down the tubing string, an output of a strain gauge for sensing the set down weight of a well tool disposed in the borehole, or an output of an inductive coupler connected to the well surface.

Abstract: A new method of standalone perforating comprises the steps of lowering a perforator part-way into a borehole on a tubing string; when perforating is desired, connecting a wireline to the perforator; disconnecting the perforator from the tubing string; lowering the perforator into the borehole to the desired depth; attaching the perforator to the borehole casing or formation by setting an anchor on the perforator; disconnecting all wireline and associated apparatus from the perforator; withdrawing the wireline apparatus to the well surface; with the perforator standing alone in the well, firing the perforator into the surrounding formation; and dropping the perforator to the bottom of the well. A new apparatus for releasing the perforator from the tubing string includes a neutral release latch mechanism, and a new anchoring apparatus includes two interleaved coil springs having beveled shaped surfaces.

Abstract: A downhole seismic exploration device comprises a seismic detector such as a geophone and a magnetic clamp, supported by O-rings in an open cradle carrier which can be secured to a cable linking several such devices into an array. The array is lowered into a cased borehole and the magnetic clamps are operated to clamp the devices temporarily to the casing. Seismic signals detected by the geophones are transmitted to the surface via the cable, the O-ring supports acting to reduce or eliminate transmission of vibrations from the borehole fluid and the cable via the carrier to the geophone. The array is then unclamped and moved to another location in the borehole and the operation repeated. The magnetic clamp comprises a rotatable permanent magnet with radial poles disposed between a pair of parallel pole piece plates protruding on each side of the device and separated by non-magnetic blocks on eahc side of the magnet.

Abstract: A monopole transmitter for a sonic well tool includes an axial tube, a piezoceramic cylinder surrounding the axial tube, an endcap disposed at each end of and firmly contacting the cylinder, and an apparatus for holding the endcaps firmly against the axial tube. The endcaps firmly contact the axial tube without simultaneously contacting an upper bulkhead. The apparatus may include spring washers disposed between the bulkhead and at least one endcap, or it may include a spring disposed between a nodal mount and each endcap. A nodal mounting tube may be disposed around the axial tube, a ring being disposed at each end of the nodal mounting tube, each ring being disposed outside of the cylinder, the apparatus including a spring disposed between each ring and an endcap outside of the cylinder for biasing the endcaps in tension against a ring thereby holding each endcap firmly in contact against the axial tube.

Abstract: A perforating gun apparatus comprises a plurality of perforating gun, each gun containing at least one charge and a novel arming, testing and firing apparatus. The arming, testing and firing apparatus arms a first charge in a lowermost perforating gun; however, the arming of the first charge in the lowermost perforating gun allows a tester disposed at the well surface to determine the identity of the lowermost perforating gun to be detonated. Furthermore, the arming of the first charge in the lowermost perforating gun also enables the arming of a second charge in an adjacent perforating gun of the gun string. In the event the first charge is not armed as expected, the arming, testing and firing apparatus in the lowermost perforating gun bypasses the lowermost perforating gun and begins to arm the second charge in the adjacent perforating gun of the gun string.

Abstract: A new borehole correction software, for use in a well logging truck computer, obtains an accurate measurement of the true conductivity of a formation in a borehole by subtracting a correction term, which is a function of the mud conductivity, the borehole radius, the standoff distance, and an estimated value of the formation conductivity, from certain raw data received by a receiver thereby producing a set of eighteen complex output voltages which represent signals that would have been recorded from the receiver had there been no borehole.

Abstract: A perforating gun having no firing head and no primary explosives is attached to a tubing string and the tubing string is run into a borehole. A new well apparatus, having a firing head, is run into the tubing string until the firing head is adjacent the perforating gun. The firing head in the well apparatus detonates, firing the perforating gun. If the firing head fails to detonate, one need only remove the well apparatus from the tubing string in order to gain access to the firing head, for repair and replacement thereof. One need not remove the tubing string to gain access to the firing head.

Abstract: A sonic well tool includes a transmitter array, including at least one monopole transmitter and at least one dipole transmitter, and a receiver array for receiving sonic pressure wave signals from a surrounding borehole formation. A first attenuation and delay apparatus is positioned above the receiver array and a second attenuation and delay apparatus is positioned below the receiver array in the sonic well tool. The first attenuation and delay apparatus includes an attenuation member comprising a plurality of interleaved rubber and metal like washers for attenuating compressional and flexural waves propagating along a metal, center support rod to the receiver array and an inner housing comprising a bellows section having a corrugated shape and a thin transverse dimension for delaying the propagation of compressional and flexural waves along the inner housing to the receiver array.

Abstract: A perforating gun, adapted to be disposed in a deviated borehole, includes an intra-gun swivel located between a first plurality of charges and a second plurality of charges of the perforating gun. The swivel includes a first housing, a second housing, and thrust and radial bearings disposed between the surfaces of the first and second housing for allowing the first housing to rotate with respect to the second housing and therefore the first plurality of charges to rotate with respect to the second plurality of charges of the perforating gun.

Abstract: A safe-arm or quick arm system for a perforating gun includes a body containing a detonator and an adapter head containing an electrical plug and a detonating cord shell, the body and associated detonator being rotatable relative to the adapter head and associated detonating cord shell. Upon rotation of the body relative to the adapter head, the detonator moves from a start position to a transport position. In this position, the plug is not electrically connected to the detonator and the leads connected to the detonator are short circuited. The detonator is not adapted to receive electrical power. Upon further rotation of the body relative to the adapter head, the detonator moves from the transport position to an electrical contact position. In this position, the plug is electrically connected to the detonator but the detonator is not aligned with the detonating cord shell.

Abstract: A new method of standalone perforating comprises the steps of lowering a perforator part-way into a borehole on a tubing string; when perforating is desired, connecting a wireline to the perforator; disconnecting the perforator from the tubing string; lowering the perforator into the borehole to the desired depth; attaching the perforator to the borehole casing or formation by setting an anchor on the perforator; disconnecting all wireline and associated apparatus from the perforator; withdrawing the wireline apparatus to the well surface; with the perforator standing alone in the well, firing the perforator into the surrounding formation; and dropping the perforator to the bottom of the well. A new apparatus for releasing the perforator from the tubing string includes a neutral release latch mechanism, and a new anchoring apparatus includes two interleaved coil springs having beveled shaped surfaces.

Abstract: A multiprocessor system includes a system of store queues and write buffers in a hierarchical first level and second level memory system including a first level store queue for storing instructions and/or data from a processor of the multiprocessor system prior to storage in a first level of cache, a second level store queue for storing the instructions and/or data from the first level store queue and a plurality of write buffers for storing the instructions and/or data from the second level store queue prior to storage in a second level of cache. The multiprocessor system includes hierarchical levels of caches, including a first level of cache associated with each processor, a single shared second level of cache shared by all the processors, and a third level of main memory connected to the shared second level cache. A first level store queue, associated with each processor, receives the data and/or instructions from its processor and stores the data and/or instructions in the first level of cache.

Abstract: Due to irregularities associated with the borehole of an oil well, a depth determination system for a well logging tool, suspended from a cable in the borehole of the oil well, produces a correction factor, which factor is added to or subtracted from a surface depth reading on a depth wheel, thereby yielding an improved indication of the depth of the tool in the borehole. The depth determination system includes an accelerometer on the tool, a depth wheel on the surface for producing a surface-correct depth reading, a computer for a well logging truck and a depth determination software stored in the memory of the computer. The software includes a novel parameter estimation routine for estimating the resonant frequency and the damping constant associated with the cable at different depths of the tool in the borehole.

Abstract: A bridge plug for sealing a well casing comprises a plurality of cups which tightly interfit together when a compressive load is applied to both opposite ends of the plurality of cups. Application of the compressive load to both opposite ends of the cups forces a first cup to fit into a second cup, the second cup to fit into a third cup, and the third cup to fit into a fourth cup, etc., thereby producing a single unitary plug which includes a plurality of tightly interfit cups. Further application of the compressive load to both opposite ends causes transverse expansion of the plurality of interfit cups to occur. When the cups contact the well casing wall, a permanent seal is achieved between the cups and the well casing wall. Anchor elements on both sides of the cups contact the well casing wall and permanently hold the interfitting cups in their compressed condition.