Abstract: Methods of sealing a wellbore include sequentially displacing a first sealant composition and a second sealant composition different from the first sealant composition into the wellbore, followed by allowing the first and second sealant compositions to set. In an embodiment, the first and second sealant compositions are pulse injected into the wellbore. The first and second sealant compositions may be arranged in an alternating, stratified pattern in the wellbore. A mechanical property of the set first sealant composition and the same mechanical property of the set second sealant composition have substantially different values. As such, an impermeable, stratified structure comprising the set sealant compositions is formed that may resist failure when at least one of them is subjected to a mechanical stress.

Abstract: The present invention provides methods and compressible foamed sealing compositions for sealing expandable pipe in well bores. The compressible sealant compositions for sealing expandable pipe are basically comprised of a hydraulic cement, a rubber latex, a rubber latex stabilizer, a gas and a mixture of foaming and foam stabilizing surfactants.

Abstract: Fracturing heads with one or more replaceable wear-resistant inserts have annular sealing elements for inhibiting fracturing fluids from circulating between the inserts and a main body of the fracturing head. Worn inserts and degraded sealing elements are easily replaced to refurbish the fracturing head without replacing or rebuilding the main body. Service life of the main body is therefore significantly prolonged. In one embodiment, an entire flow path through the main body is lined with wear-resistant replaceable inserts to further prolong the service life of the main body.

Abstract: An increase in effective propped lengths is evidenced in hydraulic fracturing treatments by the use of ultra lightweight (ULW) proppants. The ULW proppants have a density less than or equal to 2.45 g/cc and may be used as a mixture in a first proppant stage wherein at least one of the proppants is a ULW proppant. Alternatively, sequential proppant stages may be introduced into the formation wherein at least one of the proppant stages contain a ULW proppant and where at least one of the following conditions prevails: (i.) the density differential between the first proppant stage and the second proppant stage is greater than or equal to 0.2 g/cc; (ii.) both the first proppant stage and the second proppant stage contain a ULW proppant; (iii.) the rate of injection of the second proppant stage into the fracture is different from the rate of injection of the first proppant stage; or (iv.) the particle size of the second proppant stage is different from the particle size of the first proppant stage.

Abstract: An isolation system for an oil and gas well is described wherein the system comprises an isolation section and a first isolation device integral with the section and a second isolation device sealingly engaged to the section. The first isolation device may be a pressure-actuated valve and the second isolation device may be a plug.

Abstract: The side tracking system includes a window mill having a full diameter cutting surface and a reduced diameter tapered cutting surface and a whipstock having a ramp engaging the reduced diameter cutting surface. The materials of the whipstock have a first cutablity and the materials of the casing have a second cutability. The reduced diameter cutting surface contacts the whipstock ramp at a first contact area and the full diameter cutting surface contacts the wall of the casing at a second contact area. As weight is applied to the mill, there is a first contact stress at the first contact area and a second contact stress at the second contact area. A cutability ratio is the first cutability divided by the second cutability and a contact stress ratio is the first contact stress divided by the second contact stress. The mill cuts the casing rather than the whipstock by maintaining the product of the cutability ratio and the contact stress ratio less than one.

Abstract: A method for producing a gas and a liquid in a subterranean well includes the step directing a gas flow in a well annulus through one or more baffle plates to separate at least some of the liquid from the gas. The method can also include the steps of directing the separated liquid down the annulus towards a producing formation of the well, dehydrating the gas flow proximate to a surface of the well, and then directing the dehydrated gas flow to the surface. A system for performing the method includes a set of baffle plates located proximate to the producing formation configured to provide a tortuous path for the gas flow through the annulus, and a single baffle plate located proximate to the surface configured to dehydrate the gas flow. In addition to separating the liquid from the gas flow, the set of baffle plates maintains a single phase wet gas above the baffle plates, and a liquid phase below the baffle plates.

Abstract: A percussion drill bit for drilling a bore includes a drill body having a connecting section at a rear end thereof for connection to a percussive unit, and a plurality of cemented carbide buttons embedded in a front end of the drill body. Each button comprises a cemented carbide body having a rear mounting portion embedded in the drill body, and a front end protruding from the drill body. The front end of the cemented carbide button is substantially semi-spherically curved and defined by a radius whose origin is disposed axially rearwardly of a plane through the largest diameter of the button. The button projects from the drill bit body a distance which is not less than 50% of the button diameter. A conical intermediate surface forms, in cross-section, an acute angle of about 13–19° with an envelope surface of the rear mounting portion.

Abstract: The invention relates to a method of optimizing the displacement of a viscoelastic fluid in a pore, tube, duct, channel, fracture, porous medium or interconnected latticework or in an interconnected assembly of pores, tubes, ducts, channels, cavities and/or fractures using a fluid with a lower viscosity. The inventive method consists in displacing the viscoelastic fluid using a displacing fluid which supplies a signal thereto comprising pressure pulses at an optimum frequency. In this way, the moisture layer between the displaced fluid and the walls of the pores, tubes, channels, cavities, fractures or porous medium is dynamically reduced during said displacement, thereby facilitating optimum extraction.

Abstract: A portable area monitoring system for use with a horizontal directional drilling machine and adapted to produce a composite of the positions of a beacon and a fixed object. In a preferred embodiment the sensor assembly is supported by a hand-held frame and adapted to detect signals emanating from each of a beacon and a fixed object. The sensor assembly transmits the detected signals to a processor which simultaneously processes the signals to produce a composite of relative positions of the beacon and the fixed object to the frame. The composite of the relative positions of the beacon and the fixed object to the frame is communicated to the operator using a portable display.

Abstract: This invention provides a method for controlling production operations using fiber optic devices. An optical fiber carrying fiber-optic sensors is deployed downhole to provide information about downhole conditions. Parameters related to the chemicals being used for surface treatments are measured in real time and on-line, and these measured parameters are used to control the dosage of chemicals into the surface treatment system. The information is also used to control downhole devices that may be a packer, choke, sliding sleeve, perforating device, flow control valve, completion device, an anchor or any other device. Provision is also made for control of secondary recovery operations online using the downhole sensors to monitor the reservoir conditions. The present invention also provides a method of generating motive power in a wellbore utilizing optical energy. This can be done directly or indirectly, e.g., by first producing electrical energy that is then converted to another form of energy.

Abstract: A mono-diameter wellbore casing. The mono-diameter wellbore casing is formed by plastically deforming and radially expanding a first tubular member within a wellbore. A second tubular member is then plastically deformed and radially expanded in overlapping relation to the first tubular member. The second tubular member and the overlapping portion of the first tubular member are then radially expanded again.

Abstract: A downlink system that includes at least one mud pump for pumping drilling fluid from a drilling fluid storage tank to a drilling system, a standpipe in fluid communication with the mud pump and in fluid communication with the drilling system, and a return line in fluid communication with the drilling system for returning the drilling fluid to the drilling fluid storage tank is provided. A drilling fluid modulator may be in fluid communication with at least one of the group consisting of the standpipe and the return line.

Abstract: A hole cutter includes a frame and first and second blade halves moveably mounted with respect to the frame. The blade halves are first driven into the ground and then are lifted upwardly out of the new hole with as ground plug therebetween. A lift flange engages both the blade halves during this upward movement. Then the blades and the ground plug are inserted into an old hole and the blades are removed simultaneously to leave the ground plug in the old hole. The frame is longitudinally extensible to create this removal of blade halves from the old hole.

Abstract: Apparatus for cutting openings in a wall of a well. The apparatus includes a mandrel with a jetting sleeve slidably disposed about the mandrel. The mandrel has a plurality of slots defined therein and the jetting sleeve has a plurality of jetting openings aligned with the slots so that fluid will pass through the mandrel, the slots in the mandrel, and the jetting openings. The jetting nozzles are received in the jetting openings and travel in the slots in the mandrel. The flow of jetting fluid through the mandrel causes the jetting sleeve to move on the mandrel so that slots may be cut in the wall of the well.

Abstract: An aqueous, viscoelastic treating fluid gelled with a crosslinked guar or guar derivative is stabilized and improved with an effective amount of a glycol, such as ethylene glycol. These fluids are more stable in that viscosity is maintained, particularly at elevated temperatures. The additives may also increase viscosity to the point where less of a crosslinked guar or guar derivative gelling agent is required to maintain a given viscosity. These stabilized, enhanced, aqueous, viscoelastic fluids may be used as treatment fluids for subterranean hydrocarbon formations, such as in hydraulic fracturing.

Abstract: This invention provides a measurement-while-drilling (MWD) downhole assembly for use in drilling boreholes which utilizes directional formation evaluation devices on a rotating assembly in conjunction with toolface orientation sensors. The data from the toolface orientation sensors are analyzed by a processor and toolface angle measurements are determined at defined intervals. Formation evaluation sensors operate substantially independently of the toolface orientation sensors and measurements of the formation evaluation sensors are analyzed in combination with the determined toolface angle to obtain formation parameters.

Abstract: Embodiments of the invention relate to a wireline assembly that includes a coring tool for taking coring samples of the formation and a formation testing tool for taking fluid samples from the formation, where the formation testing tool is operatively connected to the coring tool. In some embodiments, the wireline assembly includes a low-power coring tool. In other embodiments, the coring tool includes a flowline for formation testing.

Abstract: The present invention may be used as an apparatus and method for extracting oil from a hydrocarbon material bearing formation. A well may be positioned in a formation having hydrocarbon material with a well casing extending into the formation that may have a number of apertures formed in the casing wall adjacent to multiple zones of interest in the formation. A hydrostatic separator may have a specific gravity approximately equal to an oil that may be extracted from the formation and may be positioned and anchored in the well casing above and adjacent to an upper level of said formation. An extraction pipe may be disposed interior to the well casing with a lower end positioned above and adjacent a separator top and may have an upper end attached at a well head. The well head may be in fluid communication with an oil storage unit and in communication with a pressure application apparatus.

Abstract: A retrievable well plug has a through shaft (12) with link connections (62, 64) and a packer element (66). By pushing the link connections (62, 64) and the packer element towards each other, the link connections (62, 64) and the packer element (66) expand radially, such that a mechanical barrier for the packer element (66) is formed. The links (76; 174, 176) have a generally T-shaped cross sectional profile and include an arm (78) with an end (80) meant for fastening to the fastening devices (72, 74). The other end of the arm (78) fastens to the second link (77) of the link connection (62, 64). Upper supporting surfaces (84, 86; 184; 192, 194) of the links (76; 174, 176) form an approximately tight mechanical barrier against the packer element (66) in an expanded position. The anchoring device (20) has a number of gripping devices (22), wherein the gripping devices (22) at setting of the well plug (10) expand radially, thereby providing an anchoring of the well plug (10) to the well bore wall.