Abstract: A method for conveying crop has a crop conveyor belt driven by a drive roller with a cylindrical roller body having an outer surface surrounding an axis of rotation of the roller for engaging an inner drive surface of a canvas wrapped therearound. The roller has a plurality of raised spaced elements such as ribs formed of a hard wear resistant material such as carbide clad onto the outer surface metal of the roller body. The ribs extend along a part only of the body at the two ends in an axial direction and angularly spaced around the outer surface. The ribs have a height less than 6 mm and a width less than 6 mm arranged such that the ribs do not engage into any recesses in the drive surface of the.

Abstract: A drive roller for a crop conveying belt has a cylindrical roller body having an outer surface surrounding an axis of rotation of the roller for engaging an inner drive surface of a canvas wrapped therearound. The roller has a plurality of raised spaced elements such as ribs formed of a hard wear resistant material such as carbide clad onto the outer surface metal of the roller body. The ribs extend along a part only of the body at the two ends in an axial direction and angularly spaced around the outer surface. The ribs have a height less than 6 mm and a width less than 6 mm arranged such that the ribs do not engage into any recesses in the drive surface of the belt.

Abstract: In a ultrasonic processing apparatus, upstream conveyor and downstream conveyor allow a fibrous web to run in a machine direction continuously. Between the conveyors, a working surface of a first mechanical element serving as a stationary element of the ultrasonic processing apparatus extends diagonally with respect to the machine direction. The fibrous web runs in the machine direction above the working surface. The ultrasonic processing apparatus includes a second mechanical element adapted to move in a direction diagonally intersecting the machine direction. The working surface of the first mechanical element cooperates with the second mechanical element to subject the fibrous web to ultrasonic processing. One of an ultrasonic horn and an anvil is used as the first mechanical element and a remainder of the ultrasonic horn and the anvil is used as the second mechanical element.

Abstract: A system and method for removing an outer layer of resilient material from an object to achieve a target outer dimension includes performing an initial cut at a cutting depth to remove an outer layer of the material. A parameter indicative of a work input to a cutter that performed the cut is acquired and used to determine the cutting depth that will be used for performing a subsequent cut to remove an additional layer. In this way, subsequent cuts are performed until the target outer dimension is achieved.

Abstract: A string-guiding structure for a curtain-reeling device substantially has a string-guiding frame mounted at an entrance of a string-guiding wheel assembly to limit the string extended from the curtain-reeling device inside the string-guiding frame and to be wound on the string-guiding wheel assembly when the string is released or collected. Therefore, the string-guiding frame depresses the oscillation and swing of the string during operation to avoid the string being jammed in the gaps of the string-guiding wheel assembly.

Abstract: An anti-strangulation apparatus for, and hanging freely with, a looped cord of a window covering device. The apparatus includes a tube. The tube at first has the looped cord of the window covering device enter therein, then has the looped cord of the window covering device exit therefrom and run therealong, and then has the looped cord of the window covering device reenter therein again where the looped cord of the window covering device is reeved, and in so doing, the anti-strangulation device is allowed to hang freely with the looped cord of the window covering device and keep the looped cord of the window covering device snug enough against the tube to prevent strangulation by the looped cord of the window covering device, while allowing the looped cord of the window covering device to remain fully operational.

Abstract: A system for attaching a shade material to a roller having recesses in its surface includes inserting portions of the shade material into an associated elongated recess and retaining the material in the recess with an attachment member having peaks and valleys along its length for intermittent engagement with the material within the recess.

Abstract: The present invention is to facilitate the attachment and maintenance work of left and right sheet guides of a shutter and to facilitate the return of the disengaged sheet. A sheet guide of a sheet shutter according to the present invention is a mechanism configured such that a sheet 2 is lifted and lowered by being wound and unwound around a sheet drum 5 supported between left and right support posts 3 and 3 according to the rotation of the sheet drum 5, and such that both the left and right ends of the sheet 2 are lifted and lowered by being guided by sheet guide sections 11 and 11 respectively installed in the support posts 3 and 3.

Abstract: Methods and apparatus to provide upper and lower travel limits for architectural opening coverings are disclosed. A disclosed architectural opening covering assembly includes a rotatable roller tube and a covering mounted to the roller tube. The covering is movable between a lowered position and a raised position. The covering is wound on the roller tube in the raised position. The covering assembly further includes a first limit nut located internal to the roller tube to define the lowered position, and a second limit nut located internal to the roller tube to define the raised position.

Abstract: A composite pull-chain disc mechanism with brake function for a door operator comprises a torsional spring having de-twisting and twisting sides. The weight of a door curtain always acts on the de-twisting sides, so that the inner diameter of the torsional spring is induced to shrink to brake the rotation of the central shaft of the door operator. If twisting sides bears an external force, the inner diameter of the torsional spring is induced to enlarge to release braking of the central shaft. Furthermore, the composite pull-chain disc mechanism can be adapted to an electric door operator. In the case of detaching an electric motor mechanism during maintenance, the door operator can still be operated to open/close a door in a manual mode through the composite pull-chain disc mechanism.

Abstract: One or more ductile metal inserts may be selectively incorporated into articles of limited ductility, including castings and molded polymers. The inserts are positioned at joint locations for joining of the article to other articles using self-piercing riveting (SPR). The inserts are of suitable ductility, thickness and strength to receive and retain self-piercing rivets and enable a strong riveted joint between the article and a second article. In an embodiment the articles are magnesium alloy castings formed by any of sand casting, die casting and semi-solid metal casting. The chemical composition of the insert may be informed by the anticipated corrosive environment of the joint and the casting temperature of the magnesium alloy. For magnesium alloy castings which may be exposed to corrosive environments, aluminum alloy inserts are preferred.

Abstract: A method and a device for remelting metal in an electric furnace includes forming a slag bath to form molten material electrodes. The molten metal of the material electrodes solidifies in block form in a crucible apparatus as a result of cooling in such a way that a block growth forms from a block base using a progressing solidification process, wherein the block base is heated by applying energy directly to the block base to influence the cooling process.

Abstract: An ingot mold has a body having an open top, a bottom with an opening, and a longitudinal cavity passing through the body. The cavity is defined by a cavity wall extending from the top to the bottom. The cavity wall has a recess adjacent the opening in the bottom of the body. A ceramic insert is positioned within the cavity such that the sidewalls of the ceramic insert are in the recess in the cavity wall.

Abstract: Methods of casting improved scroll compressor components having high quality involute portions are provided. The casting method comprises gating molten metal through a patterned region of a core or mold defining the involute vanes. In certain aspects, during casting, molten metal passes through one or more gates that extend through a core in a central patterned region that forms the involute portion of the scroll component. In certain variations, the metal comprises a gray cast iron, so the cast part comprises an involute having a matrix of pearlite and Type A graphite that is substantially free of undercooling defects. Further, in certain variations, the involute portion is substantially free of Types B-E graphite. Thus, high-quality low-defect cast scroll components are formed having good machinability and superior fatigue strength.

Abstract: Embodiments of the invention relate to a method and apparatus for continuously casting a metal slab. The method involves continuously introducing molten metal into an inlet of a casting cavity defined between advancing casting surfaces, cooling the metal in the cavity to form a metal slab, and discharging the slab from the cavity through an outlet. The casting surfaces have an ability to remove heat from the metal but this ability is reduced, thus reducing heat flux, for at least one of the casting surfaces in a region of the cavity spaced from both the inlet and the outlet and extending transversely to the casting direction. This reduced ability to remove heat is relative to such ability of the casting surface in immediately adjacent upstream and downstream regions of the cavity. The apparatus may be a twin belt caster or other form of continuous caster modified to perform the method.

Abstract: The present invention provides a structure for casting containing an organic fiber, an inorganic fiber, inorganic particles (A) having an average particle diameter of 50 to 150 ?m, and a binder (a), having a surface layer containing refractory inorganic particles (B) having an average particle diameter of 1 to 100 ?m selected from metal oxides and metal silicates, a clay mineral, and a binder (b), on the surface of the structure.

Abstract: The present invention is directed to provide a geothermal air-conditioner device utilising the earth's temperature and electrical field for processing—preheating, cooling and purifying—room intake air. This air-conditioner device includes at least one first pressure reducing chamber (1) with air intake opening (8) and second pressure reducing chamber (2) with processed air outlet (9), whereas these chambers are connected to each other by air conduits (3) located in the ground for conveying air from the first pressure reducing chamber (1) to the second pressure reducing chamber (2). The earth layer (4) on the air channels (3) is covered by a coarse material layer (5), under which at least one first ventilation conduit (6) is extending, through which coarse material layer is connected to air in chamber (1). Likewise there is exhaust ventilation piping (7) to provide exhaust from the coarse material layer (5) located.

Abstract: The invention is directed to a heat exchanger with optimal performance and a method of optimizing the performance of a heat exchanger. The heat exchanger has a first manifold, a second manifold and tubes extending therebetween. The tubes have at least one opening which extends through the entire length of the tubes.

Abstract: A cryogenic fluid vaporizer using ambient air comprising a conduit through which the fluid is passed having an outer finned tubular sleeve which includes a thermal insulation barrier between the conduit and the outer finned tubular sleeve. A fan may be included to provide an increased rate of heat transfer from the air to the outer surface of the fins of the tubular sleeve. The combination of the externally finned area and the insulating thermal barrier prevents the information of ice or frost on the exterior surface of the fins during the transfer of heat from the ambient air to the cryogenic fluid providing a frost-free cryogenic ambient air vaporizer for continuous operation.

Abstract: A media sheet for a heat exchanger is disclosed. The media sheet includes a first layer having a first outer surface and a second layer having a second outer surface. The first and second layers define a plurality of passages extending therebetween. At least one of the first and second outer surfaces comprises a plurality of depressions. The plurality of depressions further define the plurality of passages therebetween. The media sheet is polymer fiber-based and wettable.

Abstract: The invention relates to a heat exchanger plate, and a plate heat exchanger including a plurality of heat exchanger plates. Each heat exchanger plate include a heat transfer area, an edge area, that extends around and outside the heat transfer area, and a number of portholes that extend through the heat exchanger plate and are located inside and in the proximity of the edge area. The porthole is defined by a porthole edge and has a center. The porthole edge has a first edge portion, that faces the edge area, and a second edge portion that faces the heat transfer area. The first edge portion has a corrugation seen from the center of the porthole. The second edge portion has a substantially plane shape seen from the center of the porthole.

Abstract: A plate heat exchanger (100) including a number of heat exchanger plates (1), which are arranged beside each other and connected to each other by means of a braze connection to form a stack of plates (2), wherein the heat exchanger plates are substantially manufactured in stainless steel containing chromium, wherein the plate heat exchanger (100) includes a number of port channels extending through at least some of the heat exchanger plates (1), and wherein the plate heat exchanger (100) further including end plates (3, 5) covering each end of the stack of plates (2) and having port holes associated with the port channels, where at least one end plate (3, 5) has at least one port hole provided with a cover (9, 12) and where said cover includes means (9, 12) for increasing the strength and means (14, 15) for sealing off the at least one end plate (3, 5) against an adjacently arranged heat exchanger plate.

Abstract: A battery cell assembly, a heat exchanger, and a method for manufacturing the heat exchanger are provided. The heat exchanger includes a rectangular-shaped sheet having first and second rectangular-shaped sheet portions coupled together at a bent edge such that the sheet portions are disposed proximate to one another. Outer edges of the first and second rectangular-shaped sheet portions are coupled together such that an interior region is formed between the first and second rectangular-shaped sheet portions. The bent edge has first and second apertures extending therethrough. The heat exchanger further includes a first inlet port disposed on the bent edge over the first aperture, and a second outlet port disposed on the bent edge over the second aperture, such that fluid can flow through the first inlet port and into the interior region and then through the outlet port.

Abstract: The present invention relates to a system for increasing the temperature of a fluid being infused into a patient's body while the infusion is taking place. The present invention also provides for improved monitoring of air in the infusion system such to prevent the introduction of air into the patient's body receiving the fluid infusion. The present invention also provides for a system pump which provides a variable flow rate that serves a vast amount of infusion needs and purposes. A disposable cartridge in accordance with the present invention will allow for the efficient transfer of heat energy to the fluid being infused into the patient's body. The cartridge will further ensure that deleterious amounts of air will not be introduced into the patient's body.

Abstract: The present invention relates to a cooling device improving the heat transfer between a chip (2) having a semiconducting substrate (3) and a heat sink (7). The gap between a surface (11) of the chip (2) to be cooled and a surface (12) of the heat sink (7), the width of which depends on production tolerances of the elements and soldered connections, is formed as a wedge shape by an angled lower surface (12) of the heat sink, in order to create a wedge-shaped gap. A wedge element (17) having the same wedge angle as the wedge-shaped gap is inserted into said gap exactly far enough that it makes flat contact with both the chip surface (11) to be cooled and the heat sink surface (12). Dimensional deviations are thus compensated for, the use of gap fillers is avoided, and the heat transfer from the heat source to the heat sink is improved.

Abstract: A heat transfer element includes curved mounting surfaces configured to mate with an outer surface of a pipe for attachment thereto; and a channel configured to receive a tracer therein. The heat transfer element is configured to effect conductive heat transfer from the tracer to the pipe, or to process flowing through the pipe, when attached with heat transfer cement (HTC) to both the pipe and the tracer. A system includes a pipe and a tracer; HTC; and a heat transfer element having curved mounting surfaces configured to mate with an outer surface of the pipe and attached thereto via the HTC, and a channel in which the tracer is received and secured via HTC. The heat transfer element is configured to effect conductive heat transfer from the tracer to the pipe, or to process flowing through the pipe, when attached with HTC to both the pipe and the tracer.

Abstract: In a vehicular air conditioning apparatus, a first blower unit is connected by a connection duct to a side portion of a casing having respective air passages defined therein. In addition, air that is supplied to the interior of the casing from the first blower unit, and which is heated by the heater core, is blown from the fifth front passage alongside the heater core directly into the sixth front passage via sub-defroster dampers, and is blown out toward the front seat of the vehicle from a defroster blow-out port, which is disposed in the sixth front passage.

Abstract: In a vehicular air conditioning apparatus, a first partitioning member and a second partitioning member are installed at a boundary position between a first cooling section and a second cooling section of an evaporator. The evaporator is separated into the first cooling section and the second cooling section by the first and second partitioning members. In the case that air is not blown in either one of the passages that are disposed in the first cooling section and the second cooling section, air that flows through the other of the passages is prevented from flowing into the one passage through the interior of the evaporator.

Abstract: A completion assembly for subterranean use from a surface in multiple zones that are gravel packed together has a plurality of screens spaced apart with tubulars that define an annulus around them in the subterranean location for receipt of gravel in the annulus. The annulus spans multiple zones and the annulus is isolated from the surface by at least one packer. At least one barrier forming chemical is delivered from the tubulars into the annulus that has been gravel packed. The barrier chemical forms a barrier with the gravel in the annulus between at least two zones. The tubulars comprise at least one opening located between zones. A straddle tool is insertable from the surface into said tubulars to isolate the opening for chemical delivery into the annulus.

Abstract: There is provided a mobile high power laser system and conveyance structure for delivering high power laser energy to and for performing high power laser operations in remote and difficult to access locations. There is further provide such systems with high power laser, handling equipment and conveyance equipment that are configured to avoid exceeding the maximum bending radius of high power optical fibers used with the conveyance structures. There are also provided embodiments of the conveyance structures having channels, lines and passages for delivering materials such as fluids.

Abstract: An open hole packer uses mandrel expansion and a surrounding sealing element that can optionally have a swelling feature and further a seal enhancing feature of a ring with an internal taper to match an undercut on the mandrel exterior. As a swage progresses to the taper at the transition between the ring and the extending flat fingers, the fingers get plastically deformed in an outward radial direction to push out the sealing element. Shrinkage of the mandrel axially due to radial expansion brings a ring on the mandrel outer surface under the fingers to act as a support for the fingers against the seal which is pushed against the open hole. Mirror image orientations are envisioned to aid in retaining pressure differentials in opposed directions. Another external mandrel ring extends into the seal to keep its position during differential pressure loading.

Abstract: A series of ball seat assemblies preferably used to open a series of sliding sleeves for formation access to a zone that is to be fractured allows sequential shifting of the sleeves with a single ball. The ball is guided by a tapered member with a lower outlet larger than the ball. The ball lands on the segments that are initially supported. Some leakage occurs between the segments but not enough to prevent pressure buildup to shift the sleeves. The tapered member closely fits to the segments to minimize leakage. Shifting the segments axially allows them to retract so the ball passes to eventually land on a non-leaking seat so that the zone can be fractured. The ball is recovered at the surface after passing the retracted segments and going through the undistorted opening in the tapered member.

Abstract: A drilling rig with rig buffer storage and optional surge tank for receiving and processing drill cuttings and waste made of a drilling rig, having a tank in a frame with an inlet and an outlet, a moveable weir for expanding to accommodate additional drill cuttings, a central sweep member for cutting the drill cuttings and waste opposite a peripheral outer ring with peripheral cutting members, a controller for controlling rates of flow into and out of the rig buffer storage and the central sweep member rotation via a motor with reduction gear and wherein a first transportation system moves waste from the well bore to the rig buffer storage and a second transportation system moves cut waste and cut drill cuttings to a post treatment system, a skip, or a vessel for transport to another location.

Abstract: A downhole setting tool comprises a tool housing and a hollow mandrel, the mandrel being situated in the housing. The tool further comprises a piston situated between the mandrel and the tool housing and a collar situated between the mandrel and the tool housing, wherein the tool housing, the mandrel, the piston and the collar define an annulus. The tool further comprises a first valve, wherein in a closed position the first valve blocks a path of fluid communication between the interior of the mandrel and the annulus.

Abstract: A fiber support arrangement for a downhole tool includes at least one tubular and at least one bracket positioning the at least one tubular spaced radially from a downhole tool and lacking contact therewith. At least two fibers are supported at the at least one tubular with at least two of the at least two fibers having a different helical angle from one another relative to an axis of the downhole tool.

Abstract: A bow-spring centralizer (6) includes bow springs (34), moving collars (20) secured to each end of each bow spring, and interlocked stop collars (10). Extendable collars (8) may each be formed of a moving collar (20) movably interlocked with a stop collar (10). The centralizer (6) may be formed from a tube cut using a laser to create two extendable collars coupled by bow springs. Each extendable collar may include heads (12) integrally formed on extensions (26) protruding from a collar (stop collar or moving collar). The heads may be generally rectangular, arrow, or teardrop-shaped head or some other shape. Each head may be slidably captured within a chamber (24) on the interlocked collar (moving collar or stop collar). The extensions of each interlocked tubular member define the outer walls of the chamber in which a head of the interlocked tubular member is slidably captured.

Abstract: A separating device for removing sand and rock particles, and is an integral component of extraction equipment for extraction of liquids or gases from deep wells, having at least one ceramic filter module comprising: an annular stack of annular discs, the upper side of which has at least three elevations uniformly distributed over the circumference of the discs, the discs are stacked such that a separating gap for the removal of sand and rock particles is present between the individual discs, a coupling-on element at the upper end and a coupling-on element at the lower end of the annular stack, a clamping device bracing the annular stack, an outer cage, a coupling element at the upper end and a coupling element at the lower end of the filter module connecting the filter module to further components of the extraction equipment.

Abstract: A sensor used to determine the height of one or more fluids in a fluid column and to determine a location of an interface or boundary between a plurality of fluids in a fluid column is disclosed. The sensor includes a plurality of sensing elements comprising a capacitor and other components, such as resistors and inductors. The sensor also includes an oscillator that alters a frequency of an electrical current applied to the sensor, from which the dielectric constant of the fluid in which each sensing element is disposed can be determined. Methods of using such a sensor to determine the relative heights of various fluids in a fluid column are disclosed. In particular, methods of using embodiments of the invention in a well, such as water and petroleum wells, are described.

Abstract: A borehole metal member bonding system includes, a first metal member, a second metal member proximate the first metal member, and a pyrotechnic composition positioned proximate the first metal member and the second metal member configured to bond the first metal member to the second metal member subsequent undergoing an exothermic reaction while within a borehole.

Abstract: A cuttings transfer system including a separator configured to separate cuttings from a slurry and a transfer line configured to receive the cuttings from the separator. The system further including a valve in fluid communication with the transfer line and the separator, wherein the valve is configured to control a flow of the cuttings from the separator to the transfer line, and an air transfer device coupled to the transfer line that is configured to supply a flow of air through the transfer line.

Abstract: A process for enhanced oil recovery includes the steps of providing an alkali metal borohydride; providing an alkali metal bisulfite; combining the alkali metal borohydride and the alkali metal bisulfite along with water to provide an oxygen-scavenger composition; combining the oxygen-scavenger composition and an aqueous composition to provide an oil recovery solution; and introducing the oil recovery solution into an earthen formation at a pressure to provide for enhanced oil recovery.

Abstract: A method for treating a subterranean formation penetrated by a wellbore comprising combining a carrier fluid, a first amount of particulates, and a second amount of particulates into a slurry, wherein the first amount of particulates have a first average size distribution and the second amount of particulates have a second average size distribution, wherein at least one of the first amount of particulates and the second amount of particulates comprise an expanding material, placing the slurry in the wellbore, and lowering a screen into the slurry.

Abstract: The present invention relates to methods and compositions that can be used to delay crystallization of a treatment solution so that thief zones or fractures are plugged in subterranean formations at a substantial distance from a wellbore. A supersaturated sodium aluminate solution, or other solutions, are introduced into the reservoir. The solution is relatively stable in the supersaturated state. Crystallization, or de-stabilizing the solution, can be controlled, which in turn plugs the thief zone or fracture at a designed point of time. By controlling the time that crystallization starts, i.e., the induction period, thief zones that are located at a substantial distant from the wellbore can be plugged.

Abstract: The present invention includes methods and compositions relating to the setting of fluids or slurries in a wellbore. In one embodiment, a method of isolating a portion a wellbore includes preparing a sealant composition having a fluid component, a polymeric additive constituent, and a set modifier component. The sealant composition is placed into a wellbore and subjected to ionizing radiation. The ionizing radiation can cause bonding between polymeric additive constituents and create a polymer matrix within the sealant composition that increases the mechanical strength of the sealant composition. The ionizing radiation also alters the set modifier component, triggering the thickening of the sealant composition.

Abstract: A method for treating a tar sands formation includes providing heat to at least part of a hydrocarbon layer in the formation from a plurality of heaters located in the formation. The heat is allowed to transfer from the heaters to at least a portion of the formation. A viscosity of one or more zones of the hydrocarbon layer is assessed. The heating rates in the zones are varied based on the assessed viscosities. The heating rate in a first zone of the formation is greater than the heating rate in a second zone of the formation if the viscosity in the first zone is greater than the viscosity in the second zone. Fluids are produced from the formation through the production wells.

Abstract: A method for cooling a downhole gas generator that includes a combustion housing and a plurality of annular cooling jacket segments. A flow of water is provided into inlet ports, and out of outlet ports, of each of the plurality of annular cooling jacket segments, for cooling the downhole gas generator. The flow of water into the inlet ports, and out of the outlet ports is regulated to provide optimal cooling of the downhole gas generator, and to also optimize the flow of water through the plurality of apertures of the combustion housing and into the combustion chamber, to minimize heat damage to the combustion housing.

Abstract: A downhole apparatus positionable along a pipe string in a wellbore. The apparatus including a tubular structure having an outermost diameter greater than an outer diameter of an adjacent portion of the pipe string. A first end face facing a flow path in the wellbore, and at least one indentation or protuberance provided on an outer surface of the tubular structure. The at least one indentation or protuberance arranged to cause particulates in slurry within the flow path to collect and remain in a vicinity of the tubular structure. A method of diverting fracturing treatments in a wellbore is also included.

Abstract: A wellbore servicing apparatus comprising a housing substantially defining an axial flowbore and comprising one or more ports, an expandable seat, and a sliding sleeve slidably fitted within the housing, the sliding sleeve being transitional from a first position to a second position and from the second position to a third position, wherein, in the first position, the sliding sleeve does not permit fluid communication via the one or more ports and the expandable seat is retained in a narrower, non-expanded conformation, wherein, in the second position, the sliding sleeve permits fluid communication via the one or more ports and the expandable seat is retained in a narrower, non-expanded conformation, and wherein, in the third position, the sliding sleeve does not permit fluid communication via the one or more ports and the expandable seat is allowed to expand into a wider, expanded conformation.

Abstract: A method of actuating multiple valves in a well can include applying a pressure cycle to the valves without causing actuation of any of the valves, and then simultaneously reducing pressure applied to the valves, thereby actuating the valves. Another method can include releasing a locking device of each valve which prevents actuation, and then reducing pressure applied to the valves, thereby actuating the valves. A valve can include a port which provides for fluid communication between an exterior and an interior of the valve, a closure member which selectively permits and prevents fluid flow through the port, the closure member permits flow through the port in response to a decrease in a pressure differential from the interior to the exterior of the valve, and a locking device which prevents displacement of the closure member, the locking device being released in response to mechanical force applied to the locking device.

Abstract: According to one embodiment, a rotationally activated downhole well valve for connection in a tubing string is disclosed that can be repeatedly opened and closed selectively to place the tubing string in communication with the annulus. The valve is moved between the closed position and the open position by rotating the string in the first direction. In another embodiment, the valve is opened and closed by rotating the string in the first direction and is reset in the closed position by lifting and lowering the tubing string.