Abstract: A method for bonding a well bore to a casing may include several steps. Casing may be introduced into the well bore and pulses of fluid may be directed from within the casing into the well bore. An annulus between an inner surface of the well bore and an outer surface of the casing may be filled with fluid. A method for reducing fluid or gas migration into a fluid in the annulus may include inducing pressure pulses in the fluid before the fluid has cured.

Abstract: This invention relates to a method and to a tool to consolidate a wellbore by displacing conventional cement slurry or any other settable fluid, without any permanent casing. A bladder is inflated inside the bore to act as a mold and to form an annulus that can be filled by cement slurry or any other settable fluid. When the cement or the resin is set, the form is retrieved by straight pull; leaving a cement or resin sheath to support the formation without requiring any re-dulling. The sheath can be perforated if necessary (in the producing zone).

Abstract: An improved method and apparatus for dropping a ball, plug or dart during oil and gas well operations (e.g., cementing operations) employs a specially configured valving member with curved and flat portions that alternatively direct fluid flow through a bore or opening in the valving member via an inner channel or around the periphery of the valving member in an outer channel. In one embodiment, the ball(s), dart(s) or plug(s) are contained in a sliding sleeve that shifts position responsive to valve rotation.

Abstract: A percussion apparatus and method of using the percussion apparatus. The apparatus may be used for delivering an impact to a tubular string. The apparatus comprises a cylindrical member having an internal bore containing an anvil and a first guide profile. The apparatus further includes a rotor disposed within the internal bore, and wherein the rotor member comprises a body having an outer circumference with a second guide profile thereon, and wherein the rotor contains a radial hammer face. In a first position, the second external guide profile of the rotor will engage with the first guide profile of the cylindrical member so that the radial hammer face can contact the anvil. In a second position, the second guide profile of the rotor will engage with the first guide profile of the cylindrical member so that the radial hammer face is separated from the anvil shoulder. Multiple rotors and multiple stators may be employed. The rotor may be operatively associated with a stator that directs flow into the rotor.

Abstract: A method for installing a heat exchange pipe loop in a borehole, the method, in at least certain aspects, including drilling a borehole with a sonic drill system having a head and casing connected thereto, a drill apparatus on a lower end of the casing movable by the sonic drill head to drill the borehole, pumping fluid into the casing and up to earth surface in an annular space in the borehole so that drilled material flows to the earth surface, lowering a heat exchange pipe loop down into the casing, introducing grout into the casing around the heat exchange pipe loop, and extracting the casing from the borehole.

Abstract: A method for installing a heat exchange pipe loop in a borehole, the method, in at least certain aspects, including drilling a borehole with a sonic drill system having a head and casing connected thereto, a drill apparatus on a lower end of the casing movable by the sonic drill head to drill the borehole, pumping fluid into the casing and up to earth surface in an annular space in the borehole so that drilled material flows to the earth surface, lowering a heat exchange pipe loop having a lowermost U/bend member down into the casing, introducing grout into the casing around the heat exchange pipe loop, and extracting the casing from the borehole.

Abstract: The invention describes a method of cement lining a wellbore to enable a fixed sensor internal of the lining to sense characteristics of the external formations surrounding the wellbore using, at the region of the sensor position, a permeability changing device before completion of setting of the cement to create, in use, a permanent fluid communication through the cement lining between the external formation and the sensor.

Abstract: Disclosed is a method to increase the bonding forces of a hydraulic cement to a subterranean pipe (such as a casing) by the addition of at least one cementitious expansive agent to increase the bulk volume of the cement plug and a latex. The method includes positioning a platform in a downhole pipe below the desired cement plug interval, positioning a plug dump bailer tool comprising a chamber for cement slurry and a valve to discharge the cement slurry on and above the platform, and discharging the cement slurry. The cement slurry includes an expansive agent and latex to increase the shear-bond between the downhole pipe and the cement plug.

Abstract: A method for installing a heat exchange pipe loop in a borehole, the method in at least certain aspects, including drilling a borehole with a sonic drill system having a head and casing connected thereto, a drill shoe on a lower end of the casing movable by the sonic drill head to drill the borehole, pumping fluid (e.g., water and drilling fluid) into the casing, out through a lower end of the casing, and up to earth surface in an annular space in the borehole so that drilled material flows to the earth surface, lowering a heat exchange pipe loop down into the casing, introducing grout into the casing around the heat exchange pipe loop, and extracting the casing from the borehole.

Abstract: Method and composition for sealing a borehole. A chemically bonded phosphate ceramic sealant for sealing, stabilizing, or plugging boreholes is prepared by combining an oxide or hydroxide and a phosphate with water to form slurry. The slurry is introduced into the borehole where the seal, stabilization or plug is desired, and then allowed to set up to form the high strength, minimally porous sealant, which binds strongly to itself and to underground formations, steel and ceramics.

Abstract: The present invention relates to a method to increase the bonding forces of a hydraulic cement to a subterranean pipe (such as a casing) by the addition of at least one cementitious expansive agent to increase the bulk volume of the cement plug and a latex. The method of the invention includes positioning a platform in a downhole pipe below the desired cement plug interval, positioning a plug dump bailer tool comprising a tubular storing chamber for a cement slurry and a valve to discharge the cement slurry on and above the platform and discharging a cement slurry that comprises an expansive agent and a latex in quantities enough to increase the shear-bond between the downhole pipe and the cement plug. The invention allows a significant reduction of the height of the cement plug and therefore of the number of dump-bailer operations required for placing a plug.

Abstract: The invention relates to well construction and is directed at an oscillation excitation in a pipe string. According to the inventive method, an operating fluid is circulated in the pipe string. An autonomous mechanism for vibrational impact embodied in the form of an element, for instance a hollow ball having a rigid envelop and filled with gas, possessing a positive floatability, covering from 0.85 to 0.95 of a cross-sectional flow area of the pipe string and having an unrestricted degree of freedom. In the second variant, the inventive device comprises a ball support embodied in the form of a transverse beam or a crossbar rigidly connected to a spiral cylindrical spring arranged inside a tube under the ball with the aid of an easy-push fit. The spring force is selected with respect to a calculated axleload dependence on the mass of the ball and on flow strength with a basic flow rate of the operating fluid.

Abstract: An underreamer for forming a cavity from within a well bore includes a housing adapted to be disposed within the well bore. The underreamer includes at least one cutter, wherein each cutter has a first end and a second end. The first end of each cutter is pivotally coupled to the housing. The underreamer also includes an actuator slidably positioned in the housing, wherein the actuator has a first end and a second end. The underreamer includes an enlarged portion of the actuator proximate the second end of the actuator. A first axial force applied to the actuator is operable to slide the actuator relative to the housing causing the enlarged portion to contact each cutter and extend the second end of each cutter radially outward relative to the housing from a retracted position to a first position. A second axial force applied to the underreamer may be operable to further extend the second end of each cutter radially outward relative to the housing from the first position to a second position.

Abstract: Method and devices for freeing stuck pipes in wells in the absence of circulation or intensifying of inflow of fluids from a productive rock, for cleaning plugged well screens, and for improving quality of cementing of casing pipes in wells. Transverse vibrations are excited in a column of tubes in the well by axial motion of a hammer or hammers suspended inside the column of tubes on a flexible suspension support. The hammers have a maximum cross-section which is 0.90-0.98 times the inner diameter of the tubes. The hammers oscillate in a radial direction and hit the wall of tubes when the flexible suspension is pulled, thus exciting transverse vibrations in the column of tubes. The strength and repetition rate of hits can be varied depending on the speed of axial motion of the hammers, weight of a load placed under the hammers, number or shape of the hammers, spacing between the hammers, and the density or viscosity of a liquid filling the well.

Abstract: Method and composition for sealing a borehole. A chemically bonded phosphate ceramic sealant for sealing, stabilizing, or plugging boreholes is prepared by combining an oxide or hydroxide and a phosphate with water to form slurry. The slurry is introduced into the borehole where the seal, stabilization or plug is desired, and then allowed to set up to form the high strength, minimally porous sealant, which binds strongly to itself and to underground formations, steel and ceramics.

Abstract: The present invention provides a method and apparatus for plugging a wellbore in a trip saving manner. In one aspect, the invention includes a cement retainer disposed on a run-in string and a radially expanded perforating assembly disposed below the cement retainer. In a single run, the apparatus provides for perforating a wellbore and squeezing cement through the perforations and into the formation therearound. In another aspect, a method of plugging the wellbore includes running a cement retainer and a radially expanded perforating assembly into a wellbore on a run-in string. After the cement retainer is set, a firing head is actuated to cause the perforating gun to discharge. After perforations are formed, cement is introduced from the cement retainer into the isolated area and squeezed through the perforations. Thereafter, the run-in string disengages from the cement retainer leaving behind the plug formed.

Abstract: The rotating casing assembly and method, as described herein, allows for rotation of the casing at any depth to decrease the chance of microchannelling along the annulus. The assembly includes a casing section mounted through a bearing device to a casing string. The casing section is driven to rotate as permitted by the bearing by the energy of the fluid being pumped through the casing and across vanes in the casing section.

Abstract: Methods of performing down hole operations in a wellbore. A vibrational source is positioned within a tubular member such that an annulus is formed between the vibrational source and an interior surface of the tubular member. A fluid medium, such as high bulk modulus drilling mud, is disposed within the annulus. The vibrational source forms a fluid coupling with the tubular member through the fluid medium to transfer vibrational energy to the tubular member. The vibrational energy may be used, for example, to free a stuck tubular, consolidate a cement slurry and/or detect voids within a cement slurry prior to the curing thereof.

Abstract: Apparatus and process for sealing of abandoned water well bores includes a hopper for dispensing comminuted well bore packing material such as a bentonite clay onto an inclined screening surface which removes undesired fine materials. A chute for collecting material flowing off of the screening surface and directing the same into the well bore is generally funnel shaped. The apparatus includes an eccentric vibrating mechanism for vibrating the inclined screening surface to remove the undesired fine materials.

Abstract: It is common practice to rotate casing in shallow holes (to approx. 1000m). This has been found to noticeably enhance the bond between the casing and cement and wellbore wall and cement and to decrease the chance of microchannelling along the annulus. The rotating casing assembly and method, as described herein, allows for rotation of the casing at any depth. Only the lower portion is rotated. This lower portion is generally that portion crossing the production zone. This method is extremely economical compared to other methods and requires no additional rig time or surface equipment. The casing is driven to rotate by the energy of the fluid being pumped through the casing and across vanes in the casing.

Abstract: A device for making or regenerating a water well, said well comprising a casing installed inside a borehole in the ground. The device comprises a operating head with angularly equispaced radial seats in which respective punch tools for forming holes, windows or shaped cuts in the wall of the casing are slidingly housable. The head is operated from the mouth of the well to a position at a preestablished depth inside the casing so that the radial seats are orthogonal to the wall of the casing. Operating means are integral with the head to axially move the tools inside the respective radial seats to and from the wall of the casing.

Abstract: A method and apparatus are disclosed which allow isolation of a plurality of zones for treatment, particularly sand fracturing. The lowermost barrier can be pumped through tubing and anchored in cased or open holes. In the preferred embodiment, the pumped plug has a visco-elastic member which contains a particulate aggregate mixture, such as described in U.S. Pat. No. 5,417,285. The visco-elastic material is subjected to a force which changes its shape so that the material obstructs the wellbore. The shape change also accomplishes dehydration of the material within the visco-elastic enclosure by virtue of fluid displacement, resulting from a volume reduction, hardening it so that a plug using the visco-elastic material is formed. Thereafter, a packer on the tubing string is set to isolate the zone for sand fracturing. The process can be repeated without tripping out of the hole as additional plugs are pumped through tubing and the process is repeated.

Abstract: A device and its method of application is described for inserting into a shot hole which is at least partially filled with a mud suspension, the device being enclosed by a cover soluble in the mud and containing an expandable material capable of expanding upon contact with the mud and forming a plug which is capable of sealing the borehole, to include apparatus allowing the plug container to be retrieved from the borehole.

Abstract: The present invention provides an apparatus in the form of a float shoe or collar for use in cementing a casing string within a well bore. The shoe or collar has blades extending therefrom for centering the shoe or collar, as well as the lower end of the casing string, within the well bore. The blades include jetting ports positioned therein for use in jetting the formation. In an alternative embodiment, the jetting ports are located between blades which are generally convoluted and extend circumferentially part-way around the perimeter of the apparatus.

Abstract: Perforations and other openings in well casings, liners and other conduits may be substantially blocked or sealed to prevent fluid flow between the casing or liner interior and an earth formation by placing a radially expansible sleeve adjacent the perforations or openings and urging the sleeve into forcible engagement with the casing or inner wall using an explosive charge. An apparatus including a radially contracted sleeve formed by a coiled plate member or a tubular member having flutes defined by external and internal folds, may be deployed into a well casing or liner through a production or injection tubing string and on the end of a flexible cable or coilable tubing. An explosive charge disposed on the apparatus and within the sleeve may be detonated to urge the sleeve into forcible engagement with the casing inner wall.

Abstract: The invention discloses an apparatus for storing one or more constituents in a downhole tool. The constituents are segregated from each other until such time as the tool is actuated. At that time, the constituents are forced from their storage position and mixed as they are pushed from their storage position. The resultant mix is then directed to the location where the mixture will finally be placed for eventual solidification. The apparatus and method are useful for inflation of bridge plugs or external casing packers, as well as other downhole applications. Significant time is provided for the surface operator prior to initiation of the constituent elements by segregating the ingredients until shortly before they are mixed and directed to their final destination. Should a problem arise prior to mixing, the unmixed ingredients can be withdrawn from the wellbore.

Abstract: Cement bonding and bond logs in wells are significantly improved by imparting random or periodic, pulsating, oscillating or vibrating pressure to the fluids present during all stages of a cementing operation. The effect is to eliminate gelation of the fluids to improve cement placement and to enable consolidation of the cement slurry. The pressure pulses can also be detected to monitor the condition of the setting slurry.

Abstract: The current invention is an improved method for preventing annular fluid flow following primary cementing of a casing string in a wellbore. The method involves injecting high pressure pulses of a working fluid into a liquid-filled casing string to produce tube waves that will propagate through the casing liquid until they encounter a casing restriction or barrier. This encounter vibrates the casing string. Vibration of the casing string helps to maintain the pressure of the cement slurry at or above the pressure of fluids in the surrounding formations, thereby preventing or reducing annular fluid flow.

Abstract: Methods and apparatus for cementing a pipe in a well bore penetrating one or more subterranean gas-containing formations without incurring substantial gas inflow are provided. The methods basically comprise the steps of placing a hydraulic cement slurry in the annulus between the pipe and the well bore, and moving the pipe during the transition period of the slurry. The moving of the pipe maintains the hydrostatic pressure exerted by the slurry on the gas-containing formations and prevents gas flow into the slurry and the well bore. The movement of the pipe is stopped when the slurry develops sufficient gel strength to substantially block gas flow through the well bore.

Abstract: The present invention is a method of controlling this gas migration through the subsurface strata about the landfill. The method comprises the step of installing an extraction well having a zone of influence in proximity to the perimeter of the landfill. Then, there is the step of horizontally fracturing hydraulically the subsurface strata outside the perimeter of the landfill but in proximity to the perimeter of the landfill such that the resulting horizontal fractures in the subsurface strata fluidically communicate with the landfill and the zone of influence of the extraction well. The present invention also pertains to a system for controlling gas migration in subsurface strata about a landfill. The system is comprised of an extraction well which is disposed in the landfill in proximity to the landfill's perimeter. The extraction well has a zone of influence which extends beyond the perimeter of the landfill.

Abstract: A method for plugging and unplugging the slots or openings in slotted liners in wells is provided. A resin is coated onto the slotted liner by using an explosive to disperse the resin from an elongated container onto the surrounding slotted liner.

Abstract: This invention relates to flow pulsing methods and apparatus for various applications including downhole drilling equipment and in particular to an improved flow pulsing method and apparatus of this type to be connected in a drill string above a drill bit with a view to securing improvements in the drilling process.

Abstract: A method of cementing a string of casing in a well utilizes a vibrating device downhole in the well. The vibrating device locates in the string of casing near the cement shoe. Cement slurry being pumped down the string of casing will flow through the device, out the shoe and return up the annulus. Some of the cement will flow through a bypass section of the device to power the device, causing vibrations in the casing.

Abstract: A casing string is cemented in a borehole of a well. The cement is prepared by introducing water and dry cement material into a mixing vessel. The water and dry cement material are mixed in the mixing vessel to form a cement slurry. The mixing is accomplished by agitating the slurry to cause the slurry to circulate within the vessel, and while agitating the slurry, transmitting vibrational energy into the slurry and thereby aiding in the wetting of the dry cement material in the slurry. This also aids in removing entrained air from the slurry. The slurry is then pumped into an annulus between the casing string and the borehole.

Abstract: This invention relates to flow pulsing methods and apparatus for various applications including downhole drilling equipment and in particular to an improved flow pulsing method and apparatus of this type to be connected in a drill string above a drill bit with a view to securing improvements in the drilling process.

Abstract: A multiple cone, multiple bearing liner hanger for hanging a well liner for extension of the casing liner. The multiple slip cone and multiple bearing arrangement provides uniform, positive distribution of liner weight thereby facilitating hanging of heavier liner strings. The multiple bearings ensure proper rotation of the liner during cementation. The multiple cone, multiple bearing liner hanger includes an upper slip assembly with an associated bearing and a lower slip assembly with an associated bearing. The hanger is hydraulically set by first setting the upper slips and thereafter setting the lower slips. A series of shear pins ensure proper setting of the hanger to distribute the hang weight evenly over the slip cones and bearings.

Abstract: A method and apparatus are disclosed which enable one to manipulate a tubular string within a wellbore or the like to cause the area of largest standoff between the tubing and the wellbore to be moved radially at least part way around the circumference of the wellbore without the need for any axial movement of the tubular string or any device attached thereto. The method and apparatus are particularly useful for obtaining circumferentially complete distribution of cement around a tubular string in a wellbore.

Abstract: An inflatable borehole plug is disclosed, the inflation of which is achieved by chemical reaction of two co-reagents disposed therein which results in evolution of a gas. The borehole plug can be dropped or lowered down a borehole to a preselected position since the extent of gas-producing chemical reaction is able to be delayed following initiation of mixing of co-reagents, by delay means in the borehole plug, for sufficient time to enable placement of the borehole plug.

Abstract: There is claimed a method for isolating intake beds in drill holes (wells), wherein a cement slurry is pumped into a drill pipe string from a well mouth and flash setting and thickening of the cement slurry is ensured once it has left the drill pipe string and a separated phase of lower density is directed to the well mouth via an annular space of the well above a lost circulation zone. A device for carrying same into effect is also claimed.

Abstract: A method and apparatus for rotating a portion or segment of a casing string in a relatively highly deflected well bore. A straight well bore portion is provided adjacent the completion interval, beyond the deflected portion. A casing string is made up with a segment connected by a swivel to the remainder of the string. This segment is located in the straight portion of the bore. A drill string is lowered into the casing into engagment with a rotatable swivel portion fixed to the casing segment. The drill string is rotated to rotate the casing segment independently of the remainder of the casing string. This facilitates removal of excess mud cake from the annulus adjacent the casing segment, and also placement of cement in the annulus.

Abstract: An improved wireline operated oil well dump bailer includes an elongated tool body having a longitudinal bore that extends through the tool body, the bore including a chamber section for carrying cement. A port through the tool body provides fluid communication between the tool bore and the oil well bore. A piston is slidably movable within the tool body between a first position in which the piston seals the port and a second position in which the piston is spaced from the port so that well bore fluid pressure can enter the tool body through the port and communicate with the piston. A trigger carried by the tool body, preferably in the form of an explosive charge which can be activated using the wireline moves the piston away from the first position to the second position so that the well fluid pressure enters the bore and powers the piston to dispense cement from the cement carrying chamber section.

Abstract: A pipe string is suspended from the surface within a well casing installed in a well. The pipe string is centered within the casing and free from connection therewith except at a down hole point in the casing near the bottom thereof whereat the pipe is attached to the casing. Cement is flowed down the pipe string and out the bottom end thereof from where it flows up along the outer wall of the casing to form a cement annulus therearound. While the cement is being flowed, sonic energy is fed to the pipe string from a sonic oscillator attached thereto. The sonic energy travels down the pipe string and is fed to the bottom of the casing and operates to assure that the cement fills the area around the casing in a uniform manner, at the same time effecting the release of gas bubbles, dirt, rust, scale and other particles from the casing surface to facilitate the formation of a good bond between the cement and the casing wall.

Abstract: Shallow boreholes, e.g. seismic shot holes are usually sealed with cement, gravel or more recently by pouring a water swellable material such as bentonite into the hole. A more effective method of sealing involves the insertion of an impermeable bottom plug into the hole, followed by a thick layer of a particulate material such as sodium bentonite which expands when in contact with water to seal the hole. A top plug can also be used with or without a cover of cuttings to promote lateral expansion of the sealant in the hole.

Abstract: A capsule for conveying chemicals through a borehole for stopping lost circulation is totally made from a thermoplastic or fragile material or has a bottom plate made from such a material. The capsule containing the chemicals is let down until it reaches the location of the lost circulation, where the capsule is either destroyed by a drilling rod or softened by the high temperature and high pressure at the location. Thus, the chemicals are diffused.

Abstract: A capsule for conveying chemicals through a borehole for stopping lost circulation has a fragile bottom plate. A weight for destroying the bottom plate is suspended above the capsule by a cord which extends over knife edges. A messenger for cutting the cord is mounted to a wire line. The weight is caused to collide with the messenger to cut the cord, for breaking the bottom plate. Thus, the chemicals are diffused.

Abstract: A dump bailer is lowered on a wireline in a well through tubing for placing a cement slurry on a retainer located in the well. The dump bailer has a weight bar assembly that includes upper and lower sections that are extensible relative to each other. The upper weight bar section has an electrical contact that engages the electrical contact mounted in the upper end of the housing of the dump bailer. The lower section has a seal which separates the housing into upper and lower chambers. Cement is pumped in from the bottom, pushing the weight bar assembly upward until the contact on the upper weight bar section engages the upper contact. A detonator is located on the bottom of the lower weight bar section. Explosive force of the detonator transmits a shock wave through the cement slurry to expel a shear plug located on the bottom of the housing. The weight bar assembly pushes the cement from the slurry once this occurs.

Abstract: A casing in an oil well is constructed to provide for the flow of oil in the well. The casing cylindrical and may be perforated. The casing is resonant in a hoop mode at a particular fundamental frequency such as approximately 400 hertz. A transducer includes a transducer member disposed within a tubing in spaced relationship to the tubing. The transducer member may be a ceramic slotted at one end and supported by the tubing at the other end. A ring may envelope the ceramic member and may be slotted at the same position as the ceramic member. The tubing may be filled with a fluid which provides dielectric properties and operates to transmit vibrations from the transducer to the tubing. The transducer may vibrate in the hoop mode at the fundamental frequency of resonance of the casing. These vibrations are transmitted to the casing through the fluid in the tubing, the tubing and the oil in the casing to produce a resonance of the casing at the particular fundamental frequency in the hoop mode.

Abstract: A method and apparatus for forming an annulus around the outer wall of a well casing to provide a good impervious seal around such casing which is particularly useful where the casing is installed in a porous earthen formation. A first batch of cement is fed down to the bottom of an oil well casing and out the bottom thereof so that it rises up along the wall of the casing to form an annulus between the casing and the earthen formation in which it is installed. While the cement is being fed and thereafter, the casing is continually vibrated with sonic energy preferably at a frequency which sets up resonant standing wave vibration of the casing. When a layer of the cement has risen to a predetermined level, the feeding of the cement is interrupted but the sonic energization of the well casing continued.

Abstract: In forming a cement annulus around a well casing to provide an impervious seal around such casing, sonic energy is applied from a sonic oscillator to the casing and transmitted down the casing to the work area. To improve the coupling of sonic energy through the casing to the work area, the oscillator is coupled to the casing wall below the cement inlet by means of a clamp and link coupler so as to minimize the dissipation of sonic energy in the cement inlet. Further, the cement is fed to this inlet by means of a flexible hose coupling to isolate the inlet coupling and associated hardware from the sonic energy.

Abstract: A method for forming an annulus around the outer wall of a well casing to provide a good impervious seal around such casing. A wiper of a flexible soft material which mates with the inner bore of the casing is first placed in the casing at the top thereof. Cement is pumped into the casing on top of the wiper, forcing it down to the bottom of the casing, the wiper carrying mud and other foreign material with it and out of the casing. Sonic energy at a relatively low frequency (typically 15-200 Hz) is applied to the casing. A second wiper which mates with the inner walls of the casing is installed therein, this second wiper being of a rigid, relatively inflexible material.