Showing papers on "Annulus (oil well) published in 2006"

Effects of Draft Tubes on Particle Velocity Profiles in Spouted Beds

Abstract: The vertical particle velocity profiles in a full-column cylindrical conical spouted bed, with or without a draft tube, are measured using a fibre optic probe system. The profiles have different characteristics for a draft tube spouted bed (DTSB) than for a conventional spouted bed (CSB). The spout of a CSB consists of a central flow where particle velocities fit exponential distributions, and a boundary layer where particle velocities are nearly uniform. The spout of a DTSB has no boundary layer and its radial particle velocity profiles are approximately linear. The particle velocities in the spout of a DTSB increase when superficial gas velocity increases, draft tube diameter decreases, or when entrainment height decreases. A kinematic model has been used to simulate the granular flow in the annulus of a CSB and DTSB, and they are compared with the experiments. The particle velocities in the annulus of a DTSB are much lower than that of a CSB. Their radial profiles are also different with a CSB. The dependence of particle velocities in the annulus of a DTSB on superficial gas velocity, draft tube diameter, and entrainment height are also discussed. One concludes that the draft tube diameter and entrainment height are two key factors for the solid circulation rate of a DTSB.

Device and method for retrieving debris from a well

Abstract: A device for use in retrieving debris from a well, including an elongate body; a main bore extending part way along a length of the body; an opening towards a lower end of the body; a main fluid chamber in the body in fluid communication with the main bore; a flow restriction provided in the main bore, through which fluid flows from the main bore and into the main fluid chamber; at least one chamber outlet for directing fluid from the main fluid chamber into an annulus defined between the device and a well borehole wall; a return flow passage extending between the body opening and the main fluid chamber, for return flow of fluid from the annulus to the main fluid chamber, to facilitate retrieval of debris from the well; and at least one fluid exit, for flow of fluid out of the device.

Method of monitoring fluid placement during stimulation treatments

Abstract: Fluid diversion measurement systems and methods are described. One method includes inserting a tubular tubing having one more fluid injection ports into a wellbore, injecting a treatment fluid through the injection port, and determining differential flow of the treatment fluid based on measuring the concentration of at least one particular component of a wellbore fluid located in the annulus formed between the wellbore and tubular; and means for using the measured parameters in realtime to monitor, control, or both monitor and control diversion of the fluid.

One trip cemented expandable monobore liner system and method

Abstract: An apparatus to protect the mounting area of casing and a locating profile and optionally a sliding sleeve valve and a flow path from the outside of the valve to the annulus when subsequent attachment of an expanded liner is intended and the expanded liner is to be cemented in place. A barrier sleeve, nose, and outer sleeve define a sealed cavity having a loose incompressible material inside that covers the mounting location on the casing. A locating profile and an optional sliding sleeve valve and a flow path from the outside of the valve to the annulus can be provided. The cementing of the casing takes place through the barrier sleeve. After the cementing, the sleeve and nose are drilled out and the incompressible material is removed to the surface with the drill cuttings. A liner is inserted in the casing and is preferably expanded into sealing contact with the mounting location on the casing. After expansion a cement retainer positioned at the bottom of the expanded liner and the sliding sleeve located either above the mounting location of the liner in the casing shoe or in the liner below the mounted top section allow cement to be delivered outside the expanded liner and the displaced wellbore fluid to return into the casing through so that the liner can be cemented. The cement retainer can be delivered with either the liner or the expansion tools to allow expansion and cementing in a single trip. A shifting tool can be run on the expansion string to actuate the sliding sleeve and if necessary to allow for cement to be pumped from the drill string into the annulus through the sliding sleeve. The cement retainer can be milled out in a separate trip.

Casing bottom hole assembly retrieval process

Abstract: A process for retrieving a bottom hole assembly through a casing string may include: installing a casing string in a borehole, the casing string including a bottom hole assembly releasably engaged thereto and moveable through an inner diameter of the casing string; releasing the bottom hole assembly from engagement with the casing string; reducing hydrostatic pressure in the casing string inner diameter above the bottom hole assembly so that the casing string inner diameter pressure above the bottom hole assembly is lower than a fluid pressure below the bottom hole assembly; permitting reverse circulation down through an annulus between the casing string and the borehole to permit the bottom hole assembly to rise up through the casing string toward the surface; and retrieving the bottom hole assembly from the casing string.

Downhole flow control apparatus, operable via surface applied pressure

Abstract: Flow control apparatus, for placement in a downhole location in the tubing string of a well. The apparatus comprises a valve element and a lock element. Application and removal of annulus pressure (on the annulus between the tubing and the casing) permits the apparatus to be cycled between a sensitive-to-flow mode, in which it opens to permit fluids to be injected down the tubing into a subsurface formation, but closes to prevent fluid backflow from the subsurface formation into the tubing; and an insensitive-to-flow mode, in which the apparatus is open to permit unimpeded fluid flow in either direction.

Well having inductively coupled power and signal transmission

Abstract: Well for production of hydrocarbons, comprising a hole drilled down into an underground, a casing fastened to the hole wall, a production pipe that extends into the casing from the surface and down to a hydrocarbon-containing zone, a hanger on the surface in an upper end of the well, in which hanger the production pipe and casing are hung up and electrically short-circuited, and a packer arranged sealingly and electrically short-circuiting in the annulus between the production pipe and the casing, in or close to a lower end of the well, distinguished in that the well further comprises: a primary coil arranged concentrically about the production pipe, a secondary coil arranged concentrically about the production pipe, a load connected to the secondary coil, and an alternating current generator/signal unit connected to the primary coil.

System and method for reducing the borehole gap for downhole formation testing sensors

Abstract: A system and method for downhole measurement for use with drill strings to reduce the borehole gap with respect to sensors carried by the drill string. In one embodiment, the sensors are mounted on a surface of the directional drilling hinged pad that comes in contact with the borehole wall. The hinged pad is pressed against the borehole wall as contact is made with the wall, thereby keeping the sensors at a minimum gap with respect to the wall. In another embodiment, the hinged pad is not used for directional drilling. Therefore the hinged pad is extended outward to the wall with the minimum necessary amount of force. Activation of the hinged pad can be initiated, for example, by flow of mud in the annulus of the string or through a user-provided command. The sensors can include resistivity, density, neutron, electromagnetic, acoustic, seismic, and NMR measurement sensors.

Concentric coiled tubing annular fracturing string

Abstract: A concentric coiled tubing annular fracturing string is disclosed having at least two fluid flow paths. An umbilical tube located inside of a coiled tubing string may provide one of the pathways, which may be used to isolate downhole elements, such as a packer, from harmful fluids. The annulus between the umbilical tube and the outer coiled tubing may provide the second flow pathway. The umbilical tube may contain an electric line, which may provide an electrical connection to a bottom hole assembly ('BHA” ). The system may also provide for the measurement of down hole fracturing fluid pressure or be used to deliver a cross-linking agent to a specified portion of a well. The BHA may include an emergency packer deflation device to rapidly deflate a packer in the event the packer loses its ability to anchor against the casing.

Method and apparatus for conducting earth borehole operations using coiled casing

Abstract: A method and apparatus for conducting earth borehole operations include a reel (28) of continuous coiled casing (30), and an injector (20) for moving the coiled casing. The bottomhole assembly including at least a motor (54) and a bit (56) is connected to the free end of the coiled casing, and injected into the earth while circulating fluid through the coiled casing to form a drilled earth borehole having a borehole wall. The coiled casing drill string may be retrieved from the borehole, the bottomhole assembly removed, and the coiled casing again injected into the borehole, then suspended from a wellhead assembly. After severing the coiled casing, a bonding agent such as a cementitious material may be injected into the suspended coiled casing and into the annulus between the coiled casing and the borehole.

Downhole measurement of substances in formations while drilling

Abstract: A method and apparatus for measuring a substance in formations surrounding an earth borehole being drilled with a drill bit at the end of a drill string, using drilling fluid that flows downward through the drill string, exits through the drill bit entrained with drilled earth formation cuttings, and returns toward the earth's surface in the annulus between the drill string and the borehole, the method including the following steps: waiting for any of the substance that is dissolved in the drilling fluid to be substantially in equilibrium with any of the substance in the earth formation cuttings; and then measuring, downhole, the substance dissolved in the drilling fluid.

Bottomhole assembly and method for stimulating a well

Abstract: A bottomhole assembly (BHA) and method for stimulating a well includes setting a packer of the BHA in a wellbore. The BHA includes the packer and a jetting tool coupled to a tubing string. Process fluid is pumped down the tubing string and jetted with the jetting tool to perforate a formation. Stimulation process fluid is pumped down an annulus of the wellbore to fracture the formation.

A method and a device for in situ formation of a seal in an annulus in a well

Abstract: A method and a device for in situ formation of a seal (17) in a region (2) of an annulus (18) located around a pipe structure (4) in a well (18) , in which the method comprises the following steps: (A) to convey a perforation device into the pipe structure (4) to a location vis-a-vis said region (2) of the annulus (16) ; (B) by means of the perforation device, to make at least one hole (13) through the pipe wall of the pipe structure (4) at said annulus region (2) ; (C) to force a liquid sealing material, which is capable of entering into solid state, through said hole (13) and further into the annulus region (2) for the filling thereof, where-upon the sealing material enters into solid state and forms said seal (17). The distinctive characteristic of the method is that step (C) thereof also comprises: - to choose a fusible, solid-state packer material (5) as raw material for said seal material; - to heat and melt at least a part of the solid-state packer material (5) ; and - subsequently, to force liquid packer material (5) into the annulus region (2) via the at least one hole (13) through said pipe wall, whereupon the liquid packer material (5) enters into solid state and forms said seal (17) in the annulus region (2).

Structural Integrity of Casing and Cement Annulus in a Thermal Well Under Steam Stimulation

Abstract: Steam stimulation is one of the viable methods to extract heavy oii from oil sand resorvoirs. In this thermal process, the injection well is subjected to high temperatures. Numerical simulations were used to investigate the structural integrity of the well in such a high temperature environment. In this study, stresses in the metal casing, cement annulus and surrounding shale formation were examined in detail to evaluate if the induced stresses exceed the material strengths under varying boundary conditions. These include the effect of heating rate, poor cement and shale formation properties.

A method for drilling and cementing a well

Abstract: A method for drilling and cementing a borehole to access at least a portion of a formation of interest, comprising: drilling a borehole using a drill string including an external packer and a drilling assembly to access at least a portion of a formation of interest; using a drilling fluid selected to minimize adverse effects on the at least a portion of the formation of interest when drilling into the at least a portion of the formation of interest; setting the packer to create a seal in the borehole so that (i) an upper drill string/borehole annulus above the packer is isolated from (ii) a lower drill string/borehole annulus below the packer, with the at least a portion of the formation of interest being open to the lower drill string/borehole annulus; and introducing cement above the external packer into the upper drill string/borehole annulus.

Downhole impeller device

Abstract: A downhole impeller device for use within a well, comprising: a body connectable to a drill string and having an external diameter smaller than the well diameter so as to form an annulus between the body and the well; and one or more impeller members extending from the outer surface of the body such that rotation of the or each impeller member impels drilling fluid within the annulus.

Measurements of downhole mud samples

Abstract: A method for determining a property of formations surrounding an earth borehole being drilled with a drill bit (15) at the end of a drill string, using drilling fluid that flows downward through the drill string, exits through the dill bit, and returns toward the earth's surface in die annulus between the drill string and the periphery of the borehole, including the following steps: obtaining, downhole near the drill bit, a pre-bit sample (211) of the mud in the drill string as it approaches the drill bit; obtaining, downhole near the drill bit, a post-bit sample (212) of the mud in the annulus, entrained with drilled earth formation, after its egression from the drill bit; implementing pre-bit measurements on the pre-bit sample; implementing post-bit measurements on the post-bit sample; and determining a property of the formations from the post-bit measurements and the pre-bit. Measurements may be completed downhole, for example using a mass spectrometer.

Drilling a wellbore

Abstract: A method of drilling a wellbore through a subterranean formation and of strengthening the wall thereof using a drilling assembly comprising a drill string having a compaction tool 7 attached to the lower end thereof above a conventional drill bit, the compaction tool comprising a compacting means for exerting a lateral mechanical force on the wellbore wall and having a fluid passage for passing a drilling mud from the drill string to the drill bit, the method comprising: drilling the wellbore through the formation by passing the drilling mud through the fluid passage in the compaction tool to the drill bit and returning the drilling mud to the surface through an annulus formed about the drill string and simultaneously rotating the drilling assembly to effect rotation of the drill bit and of the compaction tool wherein the compacting means strengthens the wellbore wall by exerting a lateral mechanical force on the wellbore wall as the compaction tool is rotated.

Numerical Modelling of Cuttings Transport With Foam in Inclined Wells

Abstract: In this study, a 1-D transient state mechanistic model of cuttings transport with foam in inclined wells has been developed. The model is solved numerically to predict the optimum foam flow rate (liquid and gas rate) and rheological properties that would maximize cuttings transport efficiency in inclined wells. A detailed sensitivity analysis of the effect of gas and liquid flow rates, drilling rate, foam rheological properties, borehole geometry, wellbore inclination and the rate of gas and liquid influx from the reservoir on the cutting transport efficiency was presented. The cuttings transport ef- ficiency decreases with increase in well inclination from the vertical under the same flow condition. Cuttings are trans- ported more efficiently at higher gas injection rates. The influx of gas from reservoir into the wellbore has a positive effect on the cutting transport process whereas water influx has the reverse effect. The time required for achieving stabilized bot- tomhole pressure increases with increasing drilling rate and with increasing inclination of the well from the vertical posi- tion. The distribution of cuttings along the annulus is found to be not uniform, even under the steady state flow condition. The highest concentration of cuttings is always at the bottom of the hole and the lowest is at the top.

Experimental study on cuttings transport in drilling directional wells

Abstract: Cuttings transport behavior in drilling directional wells was experimentally investigated using a once-through type large-scale flow loop apparatus, the Cuttings Transport Flow Loop System (CTFLS) in the Japan Oil, Gas and Metals National Corporation Kashiwazaki Test Field. The annular test section of the CTFLS is 9-m long and consists of a 5" ID transparent casing pipe and a 2.063" OD drillpipe. The inclination of the test section can be set at an angle from 0 to 90° in 15° increments. Drillpipe can be mounted either in concentric or eccentric mode.Experiments using two types of drilling mud, water and 0.15% PHPA solution, were conducted to focus on the effects of parameters such as hole inclination angle, drillpipe eccentricity, mud flow rate, mud rheology and rate of penetration (ROP). In the test procedure, mud was circulated and cuttings were fed into the test section both at constant rates, supposing a condition of drilling with constant ROP. Then, for predetermined mud flow rates, quantitative data in steady-state condition such as volumetric concentration of cuttings in the annulus, cuttings bed height and frictional pressure loss were measured. Critical flow rate determination based on a cuttings concentration criteria defined in this study was also presented, and optimum mud flow rate in actual field operation was discussed from a more practical point of view.

Well cap method and apparatus

Abstract: A gas well cap seal assembly adapted to seal the casing bowl of a gas well and to pressurize the annulus region between the inner surface of the well bore and the outer surface of the well casing which is filled with wet cement. The pressurized annulus aids in the prevention of forming gas bubbles and gas leakage paths in the annulus region.

Pipe cleaning tool

Abstract: A method of cleaning a pipe provides a tool within the pipe. The tool has a body of smaller diameter than the pipe such that the body and pipe define an annulus and a fluid guiding member located at the annulus and movable relative to the pipe. The fluid guiding member moves relative to the pipe to guide fluid forward of the fluid guiding member to a pipe outlet.

Tubing annulus valve actuation

Abstract: A subsea wellhead assembly has a tubing hanger with a tubing annulus passage and a production passage. A metal-sealing shuttle valve is mounted in the tubing hanger for blocking upward flow through the tubing annulus passage. The shuttle valve has a retention mechanism that prevents the shuttle from moving to the open position when fluid pressure is applied from above. The running tool releases the retention mechanism after testing has been completed, causing the shuttle to close. The tree has an engaging member that can be stroked downward into the tubing hanger annulus passage to move the shuttle valve to the open position for communicating with the annulus. The running tool 111, or part of the tree, has a hydraulically driven actuator secured by threads to an engagement tool 149 having a releasable lock comprising a collet 153 with fingers 157 for engagement with a valve sleeve 163, to move it from an upper closed position to a lower open position and then to pull it upwards back to its closed position - negating the need for a return spring.

Surface controlled safety valve with pressure or temperature sensors

Abstract: A surface controlled subsurface safety valve (SCSSV) assembly 300 for use in a well (10, fig 1) includes a pressure sensor 20 or temperature sensor 302. The safety valve may comprise a flapper 74 operated using a flow tube 64. The sensor may be integrated into the same housing 62 as the safety valve. This housing may be attachable and detachable with a tubing string 14. The sensor may be used to detect pressure or temperature in the tubing string, well annulus 15 or in the control line 24 to the surface.

Pipe cleaning tool and method

Abstract: A method of cleaning a pipe provides a tool within the pipe. The tool has a body of smaller diameter than the pipe such that the body and pipe define an annulus and a fluid guiding member located at the annulus and movable relative to the pipe. The fluid guiding member moves relative to the pipe to guide fluid forward of the fluid guiding member to a pipe outlet.

Critical velocity reduction in a gas well

Abstract: Disclosed herein is a system for enhancing the recovery of gas in a perforated interval of a gas well. The system features a tubing string having a dead string attached for reducing the flow area of the annulus in the perforated interval, thereby reducing the critical velocity of the gas, i.e., the velocity required to overcome backpressure due to fluids in the well column. The system includes a ported member for receiving gas from the annulus into the tubing string. The ported member and the dead string are isolated from each other by a retrievable plug. The disclosed system provides access from the surface through the dead string for diagnostic or corrective operations. The system also provides delivery of reagents such as foamers to the perforated region to further reduce the critical velocity.

Thermal type flowmeter

Abstract: PROBLEM TO BE SOLVED: To provide a thermal type flowmeter (boundary layer flowmeter) capable of accurate flow measurement even in a wide flow measuring range wherein the flow state is shifted from a laminar flow region to a transitional region and then to a turbulent flow region in accompany with an increase of a fluid flow rate in a conventional case SOLUTION: This flowmeter has a constitution wherein a turbulent flow accelerator such as a coil 14, an annulus, a projection or a twisted tape is provided inside a part to be heated by a heater 11 of a pipe 15, to thereby disturb the flow of a fluid flowing in the pipe 15 by the turbulent flow accelerator, and the fluid is put into a turbulent flow state in the whole range of a prescribed flow measuring range of the fluid Otherwise, the fluid may be put into the turbulent flow state in the whole range of the prescribed flow measuring range, by allowing the pipe to have a structure of a plurality of steps having a plurality of pipe parts having different tube diameters, by forming at least a pipe part to be heated by the heater of the pipe to be a spiral pipe, by forming the pipe part to be heated by the heater of the pipe to be a bent pipe, or by arranging a fluid collision member in the pipe COPYRIGHT: (C)2006,JPO&NCIPI

Stuck drill pipe additive and method

Abstract: An aqueous mixture of a non-toxic, low pH, antimicrobial, acidic composition having a pH between approximately 0.5 and approximately 3.5 is used in a drilling fluid and a stuck pipe additive. One embodiment of the stuck pipe additive composition includes an alkali metal halide salt in a range of approximately 10-35 weight %; a sequenching agent in a range between 2-8 weight %, a low pH, non-toxic acid composition in a range of 0.5-20 weight percent and water in a range of 7-88.5 weight %. As a drilling fluid, it maintains well control and removes drill cuttings from holes drilled into the earth. As a spotting fluid, it frees a stuck drill stem in the annulus of a bore hole in minutes.