Showing papers on "Annulus (oil well) published in 1976"

Method and apparatus for annulus pressure responsive circulation and tester valve manipulation

Abstract: A releasably locked closed circulation valve is introduced into a well bore as part of a drill string. The annulus between the drill string and the well bore, or casing affixed to the well bore, is sealed. Pressure is applied to the annulus and the valve unlocks and opens once the annulus pressure reaches a certain level to allow circulation between the annulus and the interior of the drill string. An optional locking device preferably locks the opened valve in the open position. A second embodiment includes a tester valve simultaneously operable with the circulation valve.

Apparatus for running, setting and testing a compression-type well packoff

Abstract: An apparatus and method for running a compression-type annulus packoff on a drill or other pipe string into an oil or gas well, setting the packoff without rotating the drill string, and then shifting the axial load of the drill string from the packoff to a casing hanger or other suitable well element so that the packoff can be pressure tested under conditions closely simulating normal service conditions. The apparatus comprises an hydraulically actuated well tool that functions both as a means for connecting the packoff to the drill string on which the tool and packoff are run as an assembly into the well, and also as a means for converting hydraulic pressure in the drill string into torque and then transmitting this torque to the packoff for rotating its seal-compressing element, thereby compressing its seal into fluid-tight engagement with the adjacent well elements. The tool can be employed for running and setting a plurality of packoffs at different levels in a wellhead or other outer well element, and can be retrieved from the well after completion of the setting procedure simply by lifting the drill string.

Cleanout procedure for well with low bottom hole pressure

Abstract: A cleanout procedure for use in a well with low bottom hole pressure that has become filled with sand. It employs a conductor string of pipe and a wash string of pipe inside the conductor string, both inserted in the well. A high pressure gas is applied to the inner annulus formed by the conductor and wash string, and the workover wash fluid is circulated down the wash string up the outer annulus formed by the well casing and the conductor string, to be joined by the gas and so wash out the sand through the outer annulus. Sand is separated at the surface.

Well flow control system and method

Abstract: A well system and method for completing petroleum oil and gas wells having special application to extreme environmental settings such as platform, sub sea, and floating vessel operations, and wells in frozen regions such as the Arctic, and the like. The invention is characterized by structure effectively defining a downhole wellhead including weight supporting apparatus in which the tubing hanger is supported and a pack-off with the casing for minimizing the effects of structural damage at the surface end of the well system. The system includes a tubing hanger releasably lockable in a casing at a downhole location and having sealing means for sealing the annulus within the casing around the hanger, a valve package lock releasably lockable in the tubing hanger, tubing strings connected with the valve package lock and extending upwardly therefrom, including tubing valves, a safety joint connected with the tubing strings above the valves, tubing strings connected with the safety joint extending upwardly to a tubing head at the wellhead, control fluid conduits connected from the tubing head through the safety joint to the valve package lock and tubing hanger for manipulation of the system during various phases of operation, and a composite handling string for running and pulling the well system including either of a slip joint or a hydraulic stop and orienting tool. The system permits a downhole wellhead to be functionally created below the mudline of offshore wells, Arctic wells, and the like.

Subsurface annulus safety valve

Abstract: Disclosed is a safety system to control flow within a well which includes an annulus safety valve to control flow in the annulus between concentric well pipe and which may include a tubing safety valve to control flow in the inner pipe.

Fluid filter device for automotive power steering system

Abstract: In a fluid filter device particularly suited for installation in an automotive power steering system, a cylindrical filter element which is axially movable in a casing having inlet and outlet passages at its opposite ends includes a foraminous side wall constituting a primary filter and a valve member at one end of the filter element normally urged to engage a seat about the opening of the inlet passage by a spring acting on the filter element so that, when the primary filter becomes clogged, the buildup of the differential pressure between the inlet and outlet passages causes axial movement of the filter element for unseating the valve member and permitting the fluid to bypass the primary filter through an annular clearance between the latter and the casing wall, and a secondary filter annulus extends from the filter element across such annular clearance for filtering the fluid which bypasses the primary filter. Further, the casing wall is preferably provided with a cavity having filtered openings to the annular clearance at the down-stream side of the secondary filter annulus, and at least one bypass passage in the casing wall extending to the cavity from a port which is normally closed by the secondary filter annulus so that such port is opened to permit continued flow of filtered fluid to the annular clearance by way of the filtered openings of the cavity only when the secondary filter annulus becomes clogged to cause further axial movement of the filter element.

Well control valve apparatus

Abstract: Well control valve to be installed in a tubing string for use in killing a well through use of fluid under pressure pumped down through the annulus surrounding the tubing string. When the annulus pressure exceeds a predetermined value, the valve is opened to permit the kill fluid to flow into and through the tubing string into the producing formation. The valve contains a closure member or disc, the upstream side of which is subject to the normal hydrostatic pressure of the fluid in the annulus, and also to an increase in the pressure of the annulus fluid above normal hydrostatic pressure, but its downstream side is subjected to atmospheric pressure initially. Accordingly, the closure member can be placed in its opened condition, as by rupturing it, when subjected to a predetermined increase in annulus pressure above the normal hydrostatic pressure, allowing the annulus kill fluid to flow into and through the tubing string to the producing formation.

Method and apparatus for cleaning a screened well

Abstract: A system for developing or cleaning a screened well using dual concentric drill pipe. A blind annulus injection sub and a development head are interconnected with the drill pipe and so constructed that compressed air passing down the inner pipe is directed through nozzles in the head to agitate formation water and clear the screen. When air is passed down the pipe annulus it is injected into the inner pipe and causes formation water and sand to be drawn into the head and airlifted to the surface through the inner pipe.

Multistage, downhole, turbo-powered intensifier for drilling petroleum wells

Abstract: A turbine-powered intensifier assembly is a part of a drill collar and attaches to the downhole end of a drill string. A drilling mud stream from the drill string branches. One branch is cleaned of solid matter by centrifugal cleaners. The clean fluid drives the turbines of several stages of turbine-pump intensification and a turbine drive of the centrifugal cleaners. The turbine intakes are in parallel. Each turbine drives a pump and the pumps are staged in series so that the output of one pump becomes the input of a downstream pump. The clean fluid also supplies the pump fluid. The discharge of the final pump stage exhausts into nozzles which direct the fluid against bore hole rock at extremely high pressures and erodes the rock. Turbine exhaust and drilling mud not used in the intensification empties into the rock erosion zone to clear it of chips formed by the drilling. Fluid from this zone and dirty fluid from the cleaners pass up the annulus between the bore hole and the drill string.

Riser pipe inserts

Abstract: The riser pipe, e.g., 21 inches in diameter, extends from the ship to an anchored wellhead assembly on the ocean floor. A drill bit and drill string are guided down through the inside of the riser pipe and the anchored wellhead assembly to perform drilling operations in the ocean floor. Various strings of casing for lining the borehole wall, which is thus drilled, are run down through the interior of the riser pipe. The first string of casing run is of relatively large diameter, e.g., 20 inches in diameter followed by 133/8 or 103/4 strings. Intermediate strings are typically 95/8 or 75/8, depending on the previous string diameters. As heavier drilling muds are used, the riser tension needed to prevent buckling is increased. To reduce the tension required, we place a sleeve of low density in the annulus between the drill string and the riser pipe interior wall, leaving a much smaller annulus between the drill pipe and the insert, thus displacing the heavier mud with a lighter weight insert.

Apparatus and method for running, setting and testing a compression-type well packoff

Abstract: An apparatus and method for running a compression-type annulus packoff on a drill or other pipe string into an oil or gas well, setting the packoff without rotating the drill string, and then shifting the axial load of the drill string from the packoff to a casing hanger or other suitable well element so that the packoff can be pressure tested under conditions closely simulating normal service conditions. The apparatus comprises an hydraulically actuated well tool that functions both as a means for connecting the packoff to the drill string on which the tool and packoff are run as an assembly into the well, and also as a means for converting hydraulic pressure in the drill string into torque and then transmitting this torque to the packoff for rotating its seal-compressing element, thereby compressing its seal into fluid-tight engagement with the adjacent well elements. The tool can be employed for running and setting a plurality of packoffs at different levels in a wellhead or other outer well element, and can be retrieved from the well after completion of the setting procedure simply by lifting the drill string.

Fluid lifting apparatus

Abstract: A fluid lifting apparatus operable by air pressure applied alternately to first and second pairs of cylinders each of said cylinders having a main body part, a barrel and a bottom chamber in communications with a bottom inlet. Pressuring of the main body part of the chamber, closes a check valve at the inlet and forces fluid from the main body part, through a fluid flow valve, through the chamber and up the barrel to a production tubing segment and hence to the next higher cylinder. Emptying of the main chamber closes the fluid flow valve to prevent air from the production tubing. However, the valve is positively opened once fluid flow in the bottom chamber from the inlet is reinstituted. Air vent means to the surface and/or to the well annulus rapidly depressurizes the cylinders and hence speeds cycling between the alternate cylinder pairs.

Liquid-metal dip seal with pneumatic spring

Abstract: An improved liquid-metal dip seal for sealing the annulus between rotating plugs in the reactor vessel head of a liquid-metal fast-breeder nuclear reactor has two legs of differing widths communicating under a seal blade; the wide leg is also in communication with cover gas of the reactor and the narrow leg is also in communication with an isolated plug annulus above the seal. The annulus contains inert gas which acts as a pneumatic spring. Upon increasing cover gas pressure which depresses the level in the wide leg and greatly increases the level in the narrow leg, the pneumatic spring is compressed, and resists further level changes, thus preventing radioactive cover gas from bubbling through the seal.

Hydraulic unloading and circulating device

Abstract: The hydraulic unloading and circulating device is adapted to be inserted in a threaded joint of a well tool connected to sucker rods and including a pumping tube surrounding said tool and supported on the end of a pipe string through which said sucker rods extend, for passing fluid between the exterior of the tool and interior of the pumping tube and pipe string to the interior of the tool and well annulus to thereby relieve the difference of hydrostatic pressure between fluid in the well annulus and interior of the pumping tube and pipe string. The device itself includes a housing with a telescoping mandrel having a straight through passage and lateral port, which, when the mandrel is telescoped in the housing to a first telescoped position, the port is eclipsed and when the mandrel is telescoped upwardly from the housing to a second telescoped position, the port is exposed to thereby effect communication between fluid in the pipe string and the well annulus. Before the mandrel can be moved to its second telescoped position to effect the hydraulic static pressure equalization, it must be rotated through a given number of degrees.

Closed system for testing the condition of well bore formations

Abstract: In testing the condition of well bore formations as to fluid flow into and out of the surrounding formations and gas emission therefrom prior to cementing a production casing in the well bore, a testing fluid of a preselected density, such as a salt water solution, is pumped from a source through a treating conduit into the production casing positioned in the well bore. The testing fluid is circulated down the production casing and up the annulus between the production casing and well bore formations displacing drilling fluid and other materials therefrom. For an empty well bore the production casing and annulus are filled with the testing fluid. Samples of the fluids are directed periodically to a gas detector to test for the presence of gas emitted from the formations surrounding the well bore. Once the well bore is flushed clean, the testing fluid is conveyed through a closed circulating system of conduits to a storage vessel. The storage vessel is connected by a suction conduit to the pump that conveys the fluid from the source to the well bore. After a preselected volume of fluid is established in the storage vessel and the testing fluid is circulating through the well bore, flow from the source is terminated and the fluid level in the storage vessel is monitored for a loss of fluid into the formations surrounding the well bore or flow of fluid from the formations into the well bore.

Plastic tubing connector

Abstract: A connector for Teflon tubing having a male connector with a tapered end providing a male conical sealing surface engageable with a conforming internal conical sealing surface machined in the end of the Teflon tubing. A collet having an annular collar conforming to and surrounding the interfitting male connector and end of tubing provides with the male conical sealing surface an axially extending wedge-shaped annulus for receiving and gripping the internally tapered end of the Teflon tubing.

Cementing staging tool

Abstract: A cementing staging tool for use downhole in a borehole which is interposed in a casing string and manipulated by longitudinal and rotational movement of the upper casing string. The tool enables cement to be pumped down through the string of casing to form a lower plug. The upper casing string is then rotated and thereafter lowered to thereby open a lateral flow passageway through which cement can be pumped. The cement flows through the tool and fills the borehole annulus, thereby cementing the casing string to the borehole wall. The tool is closed by lowering the upper marginal length of the casing string. The tool maintains the ends of the casing string in captured relationship respective to one another at all times, and is left downhole as a permanent part of the casing string after the cementing operation has been completed.

Extraction of heat from sources deep in the earth crust - previous method is improved so that one borehole now does the work of two

Abstract: The present improved method envisages a single borehole divided into two by a co-axial pipe, the water passing down the annulus between the pipe and the wall of the borehole and returning inside the pipe. It sees it as possibly worthwhile to abandon the lower section of the drill at the bottom of the borehole, rather than extract it and sink a lining in its place. The upper sections of the borehole lining and co-axial tube would be insulated against heat loss; the consequential narrowing of the water channel would accelerate the flow, reducing the time taken for the heated water to pass through the cold strata of the earth which lie above the hot spot.