Abstract: A system includes a milling assembly with a mill bit and a drill string that mills a new wellbore section. The system further includes a whipstock assembly that is formed by a reamer shoe that reams an obstruction in a wellbore, a whipstock that deflects the milling assembly away from the wellbore, and a bypass valve mechanism that guides a fluid to circulate through the reamer shoe. Within the system, the milling assembly is fluidly connected to the whipstock assembly.

Abstract: A casing removal system includes a flow diversion valve. The flow diversion valve includes a flow switch that engages an upper end of an inner casing. When the flow switch engages the upper end of the inner casing, the flow diversion valve opens and at least a portion of the fluid flow through the casing removal system exhausts to the annulus. The remaining fluid flow below the flow diversion valve is insufficient to operate a mud motor that drives a casing cutter. In other embodiments, when the flow switch is not engaged with the inner wall of casing, the flow diversion valve prevents fluid flow to components that are downhole of the valve and when the flow switch is engaged with the inner wall of casing, the flow diversion valve allows for fluid flow to components that are downhole of the valve.

Abstract: A horseshoe lateral is drilled having two substantially parallel lateral sections connected with a horseshoe section. The horseshoe section may be obtained by steering a drill bit within a first plane over an in-plane angle of about 180°, and then continuing drilling along a straight path. A second lateral well system may drilled from a second borehole section, to create an additional lateral section interdigitally arranged between the previous two substantially parallel lateral sections.

Abstract: A pump down device is deployed at an anchor point in a pipe to perform a pipe severing operation. The pump down device includes: a cutting head positioned at one end of the pump down device that severs the pipe; one or more centralizers that are positioned adjacent to the cutting head and configured to provide friction for deployment of the pump down device at the anchor point and centralize the cutting head; a seal that is positioned near an end opposite to the one end of the pump down device; and an electronics housing that includes a plurality of electronic sensors. The pump down device releases an anchor mechanism upon reaching the anchor point as determined by the plurality of electronic sensors based on preprogrammed inputs. The seal prevents fluid from moving past the pump down device when in operation.

Abstract: A controlled rate of propagation of the fluid saturation front or thermal front is desired in may oil and gas and geothermal operations. Natural fractures and fractures created during hydraulic stimulation may have heterogeneous hydraulic properties resulting in uneven flow distributions, therefore leading to short-circuiting and breakthrough issues. The present invention relates to wellbores connected hydraulically by multiple fracture zones; methods are directed to control for even flow distribution among fractures, regardless of heterogeneities in fracture hydraulic properties, and to control propagation of saturation fronts and thermal fronts in subsurface reservoirs.

Abstract: A perforating gun for use in oil and gas operations. The gun is carried to a desired area of a wellbore using only fluid pressure. The gun comprises a charge housing disposed within a removable sleeve. The charge housing comprises a plurality of shaped charges in communication with one or more sensors. The sensors are programmed to initiate the detonation sequence of the shaped charges upon measuring set parameters. Upon detonation, the gun fragments into a plurality of pieces that may be washed away from the detonation site.

Abstract: A downhole autonomous cutting tool and methods are described. The downhole autonomous cutting tool including: a body comprising a hydraulic motor, the body having a generally cylindrical configuration such that the body limits a downhole flow of fluids past the autonomous cutting tool between the autonomous cutting tool and the pipe when the tool is deployed in the pipe; a locking unit attached to the body, the locking unit actuable to engage inner surfaces of the pipe in the wellbore; a sensor module operable to detect interactions between the pipe and walls of the wellbore; an actuation unit attached to the body and rotatable by the hydraulic motor, the actuation unit operable to move a plurality of cutting elements between a running position and a cutting position; and a control unit in electronic communication with the sensor module, the locking unit, and the actuation unit.

Abstract: The embodiments include methods and tools to activate downhole apparatuses. In one embodiment, a hydrostatic pressure intensifier includes a housing having at least two different internal cross-sectional surface areas. The housing includes a device mounted on the housing and operable to actuate in response to being subject to a threshold amount of pressure. The housing also includes a first piston housed in a first chamber of the housing, where the first piston has a first cross-sectional area and a first stroke length, and a second piston housed in a second chamber of the housing, where the second piston has a second cross-sectional area and a second stroke length, and where the first cross-sectional area is greater than the second cross-sectional area. The hydrostatic pressure intensifier also includes a fluid flow restrictor that restricts fluid flow through the valve to control an amount of pressure applied by the first piston.

Abstract: An illustrative hydraulic fracturing flow simulation method includes: identifying a network of fractures within a formation rock matrix; modeling each fracture in the network as fluid flow path having discrete points at which a fluid pressure is determined; representing the rock matrix with discrete nodes at which a fluid-solid interaction force is determined, each said discrete node being associated with multiple discrete points along a fluid flow path; deriving the fluid-solid interaction force for each node from the fluid pressure at the associated discrete points; estimating an extent of fracture propagation based in part on the fluid-solid interaction forces; and displaying a visual representation of the fracture propagation extent.

Abstract: A soluble abrasive cutting tool is configured to perform a cutting operation in a wellbore. The cutting operation comprising directing a pressurized stream of an abrasive fluid containing abrasive particles at a surface in the wellbore. For example, a stream of abrasive particles can be directed via a nozzle on the cutting tool at casing in the wellbore to perforate the casing. The abrasive particles are selected to dissolve in the wellbore fluid after the cutting operations have been completed. Once dissolved, the wellbore fluid can be removed from the area of the cutting operations without clogging tubing or pumps used to remove the wellbore fluid.

Abstract: A multi-string section milling tool has a longitudinally extending tubular body with mill carriers carrying hardened cutters that pivotally extend from a mill window in the tubular body by upward movement of a drive plunger. A downwardly biased piston mounted to the upper end of a flow tube is slidably inserted through a stationary thimble below the piston. The lower end of the flow tube is attached to a drive plunger which is pivotally attached to drive yoke links pivotally attached the mill carriers. The piston and thimble creates a pressure chamber in the milling tool. Fluid pressure in the pressure chamber moves the piston, flow tube and drive plunger upward to pivotally extend the drive yoke links and mill carriers radially outward through the mill window. Cessation of fluid pressure in the pressure chamber retracts the mill carriers.

Abstract: A piston initiator is used on an assembly having a milling tool and a whipstock for creating a sidetrack in a wellbore. A piston disposed in an uphole position in a bore of the milling tool seals the bore from communicating with the port. A line from the port can communicate pressure to components on the whipstock for initiating their activation. The piston is movable from the uphole position, but is held by a releasable connection configured to release the piston in response to a predetermined force from fluid flow in a downhole direction against an exposed surface area of the piston. An uphole shoulder in the milling tool prevents movement of the piston in an uphole direction so the piston does not stress the releasable connection in response to reverse fluid flow through the milling tool.

Abstract: A method for leakage detection of underground pipeline corridor based on dynamic infrared thermal image processing. The leakage can be detected by the following steps, including: converting infrared thermal videos into infrared thermal images; obtaining the gray scale information and temperature information of internal environment of the underground pipeline corridor. The gray scale information can realize the conventional target of pipe line state identification inside the pipeline corridor, and the temperature information can be used to detect the pipe leakage.

Abstract: A method for performing a formation fluid test in a borehole penetrating a subsurface formation includes disposing a fluid tester in the borehole, extracting a sample of fluid from the subsurface formation using the fluid tester, and analyzing the sample using the fluid tester to provide test data for a process used to analyze the sample. The method also includes fitting an equation to the test data and calculating a ratio of a first derivative of the equation to a second derivative of the equation. The method further includes continuing to extract the sample from the subsurface formation in response to the ratio indicating a clean sample will be forthcoming and terminating the extracting of the sample from the subsurface formation in response to the ratio indicating a clean sample will not be forthcoming.

Abstract: In some embodiments, a method for executing an emergency disconnect sequence in shallow water depth includes unlatching a lower marine riser package (LMRP) of a blowout preventer (BOP) from a lower stack of the BOP. The BOP defines a wellbore fluidically coupled to the subsea wellhead. A tubular is disposed within the wellbore. The method further includes shearing the tubular and sealing the wellbore. In response to an indication that a vessel operably coupled to the BOP has failed to keep station, an unlatch sequence and a shear and seal sequence are initiated, such that each sequence occurs at least partially simultaneously. The unlatch sequence includes disconnecting the LMRP from the lower stack, and the shear and seal sequence includes activating the lower stack to shear the tubular in less than about one second and seal the wellbore.

Abstract: An apparatus for performing a milling operation includes a mill having an internal fluid conduit and a fluid port configured to connect the internal fluid conduit to an exterior of the mill. A moveable flow diversion component is configured to move axially in the internal conduit from a first axial position in which fluid is prevented from flowing between the internal fluid conduit and the fluid port, to a second axial position in which the internal fluid conduit is in fluid communication with the fluid port. The apparatus also includes one or more slots configured to engage one or more pins extending into the internal fluid conduit, the one or more slots defining a path that directs movement of the flow diversion component. The flow diversion component is configured to be moved from the first to the second axial position by changing fluid pressure in the internal fluid conduit.

Abstract: A method includes cutting a production tubing disposed in a wellbore to form a lower production tubing section and an upper production tubing section, displacing the upper production tubing section away from the lower production tubing section, installing a production tubing conversion device within the upper production tubing section, and injecting a sealant into the wellbore through the upper production tubing section, through the production tubing conversion device, and through the bottom hole assembly. The production tubing conversion device is coupled to a bottom hole assembly disposed below the production tubing conversion device.

Abstract: A drill bit forming a borehole in the earth may be urged sideways, creating a curve in the borehole, by a cross-sectional shape of the borehole. For example, a borehole with a cross-sectional shape comprising two circular arcs of distinct radii, one larger and one smaller than a gauge of the drill bit, may push the drill bit away from the smaller circular arc and into the larger circular arc. Forming a borehole with such circular arcs may be accomplished by extending a cutting element from a side of the drill bit for only a portion of a full rotation of the drill bit. The relative radii and angular ranges occupied by the circular arcs may affect a radius of curvature formed in the borehole. The radii and angular ranges occupied by these circular arcs may be adjusted by altering the timing of extension and retraction of the extendable cutting element.

Abstract: A cutting system is used for cutting a hollow cylindrical support beam which forms part of a support structure of a sea platform. The cutting system comprises a fixating device to fixate the cutting system in an operation position around an outer wall of the support beam, and a drilling device to drill a series of through holes in the outer wall and around the support beam. The drilling device is movable along a drill track and around the support beam by a drill driver.

Abstract: This disclosure may generally relate to drilling operations and, more particularly, to systems and methods for sidetracking an existing well. A bottom hole assembly may comprise a milling assembly, a whipstock coupled to the milling assembly, wherein the whipstock comprises an inclined ramp configured for diverting the milling assembly toward a casing string, and a downhole subassembly coupled to the whipstock, wherein the downhole subassembly comprises a body portion and one or more components on the body portion operable to weaken and/or remove material from the casing string.

Abstract: A horseshoe lateral is drilled having two substantially parallel lateral sections connected with a horseshoe section. The horseshoe section may be obtained by steering a drill bit within a plane over an in-plane angle of more than 90°, and then continuing drilling along a straight path. The horseshoe section comprises a part that is tangential to a drilling rights limit line of a drilling plot.

Abstract: A straddle packer has a floating auto-J sleeve that automatically shifts the straddle packer from a run-in condition to a stay-set condition after pumping of high-pressure fluid into the straddle packer in excess of a predetermined pump rate is terminated. In the stay set condition, packer elements of the straddle packer remain in sealing contact with a well casing or well bore into which the straddle packer has been run.

Abstract: A ported casing collar. The ported casing collar comprises a tubular body defining an outer sleeve. At least first and second portals are placed along the outer sleeve. The casing collar also comprises an inner sleeve. The inner sleeve defines a cylindrical body rotatably residing within the outer sleeve. The inner sleeve contains a plurality of inner portals. A control slot is provided along an outer diameter of the inner sleeve. In addition, a pair of torque pins are provided, configured to ride along the control slot in order to place selected inner portals of the inner sleeve with the first and second portals of the outer sleeve. Preferably, the setting tool is a whipstock configured to receive a jetting hose and connected jetting nozzle. A method of accessing a rock matrix in a subsurface formation is also provided.

Abstract: A perforating gun system with at least one gun. Each of the perforating guns have charges disposed in a gun carrier that are angled to the longitudinal axis of the gun to achieve a predetermined proppant transport profile into clusters within a stage in a well casing. The perforation tunnels may also have burrs on each side of the casing and acts in initially aiding proppant transport during fracture treatment. A method of tuning a cluster to achieve a desired fracturing treatment based on a feedback from another cluster includes selecting a hole diameter, a hole angle for creating an angled opening, a discharge coefficient, and a proppant efficiency. Moreover, a method of improving perforation charge efficiency.

Abstract: Apparatus having a focused transducer and methods of operating a focused transducer downhole in a well can provide high resolution downhole imaging. In various embodiments, a focused transducer is used for imaging downhole in a well in which the imaging is based on a seismoelectric effect. In various embodiments, a focused transducer is used for imaging downhole in a well in which the imaging is based on an electroacoustic effect. Additional apparatus, systems, and methods are disclosed.

Abstract: An apparatus for electrically machining including a rotatable shaft and an electrode for electrically machining is disclosed. The electrode is movably connected to the rotatable shaft. When the rotatable shaft is rotated, the electrode rotates together with the rotatable shaft and moves relative to the rotatable shaft under an action of centrifugal force. Further disclosed is a method for electrically machining including: movably connecting an electrode to a rotatable shaft; inserting the rotatable shaft into a hole in a workpiece, and keeping a gap between the electrode and the workpiece, wherein the hole has a first diameter; powering on the electrode and the workpiece; rotating the rotatable shaft in the hole to generate centrifugal force; and pushing the electrode relative to the rotatable shaft towards the workpiece under an action of the centrifugal force to remove a portion of a material of the hole.

Abstract: An apparatus for removing at least a section of a tubular includes an axially elongated body configured to be advanced through an inner tubular in a borehole to a selected location, the inner tubular disposed within an outer tubular in the borehole and having a diameter that is less than a diameter of the outer tubular. The apparatus also includes a cutter configured to be actuated between a closed position in which the cutter is disposed within the body and an open position in which the cutter extends radially, the cutter having a length sufficient to engage and cut the outer tubular, the cutter configured to be advanced in an axial cutting direction as the outer tubular is cut. The apparatus further includes an automatic stabilization member disposed on the cutter, the stabilization member configured to restrict lateral movement of the cutter by contacting the outer tubular during cutting.

Abstract: A system and a method of providing a reliable and consistent time delay in an oil and gas exploration/recovery device inserted in a bore hole is presented. The reliability and consistency of the time delay is a result of the use of electronic circuitry in determining the length of time delay. The system and method presented provide a time delay unit that is modular/commoditized, facilitating quick and easy integration of each component of the time delay unit in the field. Further, assembly and disassembly of the time delay unit is easily accomplished in the field and may be designed to operate with standard percussion and detonation elements.

Abstract: Apparatus, systems and methods provide protection for components of a downhole tool by using a liner and/or web protector to minimize, block, or prevent erosion of a pillar component, which is adjacent to an opening of the downhole tool, during activation and operation of the downhole tool. The downhole tool comprises a body having an external surface and internal volume configured to store thermite fuel, wherein the thermite fuel is configured to ignite into a molten thermite fuel. The downhole tool comprises an opening extending from the internal volume through the external surface, and a pillar defining one side of the opening, wherein the opening is configured to project the molten thermite fuel. The downhole tool includes web protectors, abutting at least an internal side of the pillar, to block the molten thermite fuel from impinging the internal side of the pillar, thus protecting the components of the downhole tool.

Abstract: An apparatus for removing rubber stator material from inside a housing includes a head, at least one blade, and an actuator. For example, the apparatus can be used to core out rubber material from the housing so new material can be molded therein. Also, the apparatus can be used to cut back excess rubber material newly molded in the housing. The head is rotated about an axis and is moved along the axis relative to the housing. The at least one blade is pivotably connected to the head and removes the rubber stator material at least partially from inside the housing with the rotation and movement of the head through the housing. The actuator is associated with the at least one blade and is operable to adjust a pivot of the at least one blade relative to the head.

Abstract: A cutting device using an ultrahigh pressure (UHP) hose carrying UHP fluid is designed to be inserted into a pipe or tube and cut the same from the inside out. In one example, the cutting device is for insertion into a wellbore for cutting the casing of the wellbore from within the wellbore with a revolvable UHP hose. The cutting head which effectuates the cut may be centered by a centering device that is generally conical in shape such that a portion of the centering device remains exterior to the pipe or tube as the UHP revolves during the cutting action.

Abstract: A downhole sensor deployment assembly includes a body attachable to a completion string and one or more arms pivotably coupled to the body. A sensor pad is coupled to each arm and movable from a retracted position, where the sensor pad is stowed adjacent the completion string, and an actuated position, where the sensor pad is extended radially away from the completion string. One or more actuators are pivotably coupled to the body at a first end and pivotably coupled to a corresponding one of the one or more arms at a second end, the one or more actuators being operable to move the sensor pad to the actuated position. One or more sensor devices are coupled to the sensor pad for determining a resistivity of a formation, the one or more sensor devices comprising at least one of a sensing electrode, a transceiver, and a transmitter.

Abstract: A subsea compact cutting system operable for cutting pipe utilizing two gates. Each gate preferably has a blanking portion and an opening through the gate. A first gate is moveable only between an open throughbore position and a partially open throughbore position. A second gate is moveable between an open throughbore position and a closed throughbore position. To cut pipe and seal off the throughbore, the first gate is moved to a position where a cutting element on the first gate is centrally located in the throughbore. The second gate moves to seal the throughbore. A cutting element on the second gate interacts with the cutting element on the first gate to cut pipe in the throughbore.

Abstract: Systems, tools, and methods include using a milling assembly with a mill having multiple, different types of cutting element inserts. A gage region of the mill includes a first type of cutting element insert, and a shoulder region of the mill includes a second type of cutting element insert. One cutting element insert may include chip-breaking features, and the other may be a shear or gouging cutting element.

Abstract: Systems and methods to maintain constant pressure within a chamber within a tool via a sliding seal, wherein the seal moves to increase or decrease the size of the chamber.

Abstract: A multi-stage stimulating system is provided. The system is wireline deployed comprises one or more hydraulic sealing devices, hydraulic anchors and a mechanical cutter or a shifting tool, further comprising an accumulator-pump unit in the system to provide a fluid source for hydraulically actuating the sealing devices, anchors and cutter. A method is further provided of stimulating multiple intervals of a subterranean formation by running a bottom hole assembly down a wellbore casing on a wireline.

Abstract: A blind shear ram includes an upper carrier including an upper blade and a lower carrier including a lower blade. The upper carrier and the lower carrier are positionable in a first position in which the upper carrier and the lower carrier are spaced apart and a second position in which the upper carrier and the lower carrier seal a wellbore. The upper blade and the lower blade are configured to cut at least one pipe and at least one cable when the upper carrier and the lower carrier move between the first position and the second position. At least one of the upper blade and the lower blade includes a textured surface configured to induce friction between the at least one cable and the blade.

Abstract: A downhole valve has a housing with a longitudinal main passage and at least one valve port extending from the main passage and through the housing, a valve member is arranged in the main passage, the valve member arranged to cover the at least one valve port, wherein at least a part of the valve member is made of a degradable material which is reactive to water or a well fluid, and has a surface coating of a material which is non-reactive to water or the well fluid.

Abstract: The present invention relates to a downhole completion device configured to be mounted as part of a well tubular metal structure. The downhole completion device comprises a housing enclosing a closed space, an electrical component arranged in the space inside the housing, the housing being filled with a liquid having a first volume of 1 bar at 20° C., wherein the housing has a first housing section and a second housing section, the first housing section having a first thickness and the second housing section having a second thickness, and the second thickness being smaller than the first thickness so that the second housing section is more flexible than the first housing section. Furthermore, the invention relates to a downhole completion system.

Abstract: A one trip bottom hole assembly allows setting and testing a plug and release from the plug. Cement can be pumped onto the plug, after the BHA is raised, to an extent to meet local regulatory requirements. The cutter spear combination can be activated with pressure built on a second dropped ball larger than the first ball to release the blades for extension with fluid circulation. The circulation path through the spear is opened using pipe manipulation during the spear setting sequence. The cuttings from severing the tubular fall onto the cement. The spear is set with string manipulation as the drill string rotates the blades while maintaining the string under tension. The spear can be released and repositioned for the top of the string to facilitate removal and disassembly at the surface. All the above described operations are accomplished with a single trip into the hole.

Abstract: A method and apparatus for cutting and pulling a casing string from a well. A downhole casing pulling tool includes a tubular housing having a bore therethrough, a packer assembly configured to isolate an annulus between a casing and the tool, a slip assembly configured to engage the casing, and a piston assembly disposed in the bore of the tubular housing. The piston assembly is configured to operate an actuator, wherein the actuator is configured to operate at least one of the packer assembly and the slip assembly and modify a fluid pressure in the bore of the tubular housing.

Abstract: A dual coiled tubing head has an outer coiled tubing connector, an inner coiled tubing connector, a central housing and a bottom housing. The inner coiled tubing connector fits within the outer coiled tubing connector such that a passage is created between the inner coiled tubing connector and the outer coiled tubing connector to allow for the passage of fluid through the outer coiled tubing connector. A central housing is connected to the outer and inner coiled tubing connectors. The central housing has a central passage, a peripheral downhole passage and an outlet. The peripheral downhole passages are in fluid communication with the outer coiled tubing connector. The bottom housing connects to the central housing. The bottom housing has a central passage. The central passage is in fluid communication with the peripheral downhole passages for permitting downhole flow of fluid from the exterior coiled tubing connector.

Abstract: A wellbore intervention tool for use in penetrating an obstruction in a wellbore includes a cutting tool having at least one rotating cutter member for penetrating the obstruction. A displacement mechanism coupled to the cutting tool sets and adjusts a cutting position of the cutting tool relative to a tool axis. A sweeper coupled to the displacement mechanism deflects the displacement mechanism about the tool axis, and the cutting tool is deflected with the displacement mechanism.

Abstract: A tubeless spoked wheel including a rim and a hub connected with wire spokes includes a rim that has no through-hole and is narrow in the vehicle width direction. A plurality of internal threads are aligned circumferentially in an annular raised portion arranged along the centerline of a rim. A connecting member that is hollow and has an external thread on its outer periphery is screwed into each internal thread. Each connecting member is pre-engaged with a distal end of a spoke in a rotatable manner. Each spoke bends at a position outward from the connecting member, tilts toward a hub, and has its basal end connected to a right or left flange of the hub with a nipple. The spokes are connected to the annular raised portion to narrow the rim in the vehicle width direction. The spokes are rotatably supported on the connecting members.

Abstract: Methods and apparatus include mechanically perforating a tubular positioned in a subterranean wellbore. A plurality of mechanical penetrators are moved radially outward, simultaneously or sequentially, in response to an actuating force applied from a downhole power unit or tubing pressure. After perforating the downhole tubular, the penetrators are retracted for re-use at a new location or for retrieval. A slip assembly can secure the tool in position during use.

Abstract: A liquid propellant driven hydraulic pressure supply device may include an elongated body having an internal bore extending from a power end to a discharge end having a discharge port, a hydraulic fluid disposed in the bore between a piston and the discharge end and a liquid propellant gas generator connected to the power end.

Abstract: This invention relates to a cutting unit for a well pipe.

Abstract: A system including a gripping tool and a rotary cutting tool may be used to grip a section of casing while cutting through a lower portion of the casing in a single trip. The gripping tool includes a mandrel with a flow bore extending therethrough, a slip actuator received on the mandrel, at least one slip corresponding to the slip actuator, a housing disposed around at least a proximal end of the mandrel, and a collet assembly disposed proximate the at least one slip. The rotary cutting tool is coupled to the mandrel. The gripping tool also includes a bearing assembly that enables the mandrel and the rotary cutting tool to rotate while the at least one slip is remains stationary engaging an interior wall of a casing. The system may include a hydraulic power section to help with setting the slips and removing the cut casing from the wellbore.

Abstract: A method for determining a material in an annulus between two objects disposed in a borehole includes positioning logging tools in the borehole, each of the logging tools being oriented at a different angle. The method also includes measuring a property of the material in the annulus using the logging tools and determining the material in the annulus based on the measured property.

Abstract: A method is for establishment of a new well path from a well. The method comprises disposing and anchoring a plug base in a casing in the well; lowering a perforation tool into the casing; forming holes in the casing along a longitudinal section; pumping a flushing fluid out through outlets in a flushing tool and into the casing and further out into an annulus; pumping a fluidized plugging material out through the flushing tool and into the casing and further out into the annulus; placing the fluidized plugging material along the longitudinal section so as to form a plug across a cross section of the well; wherein the outlets in the flushing tool are angled non-perpendicularly relative to a longitudinal axis of the flushing tool.