Abstract: A casing brush for cleaning the walls of a well casing, the casing brush comprising a body (1) in which are mounted cleaning bristles (2) and an adapter (4) to connect the upper end of the body (1) to the lower end of a bridge plug. The body (1) and the adapter (4) are comprised of a material which is at least drillable by a rock bit.

Abstract: A traction apparatus (1A) includes at least one traction member (51) when engages a surface (10A) against which traction is to be provided. The traction member can move relatively freely in one direction over the surface but has high resistance to movement in the other direction. The apparatus can be made to move by having a number of traction members (51-56) which move or oscillate relative to each other. There are preferably a large number of traction members which are in the forms of bristles in a brushlike part of the apparatus. The apparatus is suitable for use in down-hole tools. The bristles are bent in a first direction by being constrained in a hole facilitating movement in the opposite direction but preventing movement in the first direction.

Abstract: A stand-off device for tubulars comprising a sleeve adapted to fit around a tubular, the sleeve comprising an outer surface and a plurality of blades extending along the outer surface of the sleeve, the blades comprising a bearing surface, wherein the bearing surface of each blade is curved longitudinally. The device may be metallic or non-metallic. Non-metallic devices further comprise a protective coating to inhibit abrasion, corrosion, sparking, and electrolysis. The stand-off device is particularly suitable for use with casing in deviated wellbores.

Abstract: A casing scraper comprises a generally cylindrical body (1) adapted for connection at one end to a drill string, having a plurality of scraping or scouring elements (2) disposed around the outer surface thereof. A pipe (6) extends through the cylindrical body (1). One end of the pipe (6) is adapted for connection to a source of cleaning fluid and the other end is connected to a tail pipe (7). The tail pipe (7) has at least one opening (8) in it through which cleaning fluid may be circulated into the well casing. The casing scraper further comprises filtration means (4) located above the openings (8) in the tail pipe (7) and remotely operable means (9, 10) for selectively directing the flow of cleaning fluid from passing outside the filtration means (4) to passing through the filtration means (4).

Abstract: An automatic paraffin removal unit, comprises a scraper body (3), a tumbler(4), an arc spring leaf (2) and a return torque spring(16), and the upper, lower commutators consist of a sleeve(1), an open spacing ring(5) and a tower spring(6). In operation, the scraper is clamped on a pumping rod(9), while the upper, lower commutators are respectively connected to the upper, lower ends of the tubing section from the well head to the section having toe temperature lower than paraffin deposition temperature requiring paraffin removal, the scraper moves up and down following the pumping rod, via unidirectional upward or downward movement, paraffin removal is performed to the inner wall of tubing and pumping rod unceasingly, and variations in direction being performed in the upper, lower commutators. The apparatus has the features of a reasonable structure, simple and convenient in mounting, able to perform reliable automatic running and long service life.

Abstract: A down-hole tool 1 has a body of varying cross-sectional diameter to correspond with a stepped profile of a well bore, such as at the well head. The tool is provided with cleaning members, such as bristles, and fluid circulation paths terminating in radial outlets 11 for cleaning otherwise difficult formations or profiles.

Abstract: A tubular body or mandrel incorporated into a string of tubular pipe, on which first and second swab cups and a casing scraper are mounted, is run into a cased earth borehole to displace a first fluid in the borehole, usually a drilling fluid, with a second fluid, usually either a completion fluid or a workover fluid. In a first embodiment, reverse circulation, in which the second fluid is pumped into the borehole annulus above the swab cups, and in which the first fluid is thereby pumped back towards the earth's surface through the interior of the string of tubular pipe, causes displacement of the first fluid merely by lowering the string of pipe while pumping the second fluid into the borehole annulus. In a second embodiment, using normal circulation, the first fluid is pumped from the earth's surface downwardly through the interior of the string of tubular pipe into the borehole annulus between the pair of swab cups.

Abstract: A downhole tool for cleaning internal surfaces of subsea drilling rig equipment, including drilling risers, blowout preventor assemblies and wellhead assemblies, as well as for retrieving wear bushings, comprising an elongated support body, at least a pair of scraper blades and wash ports. A unique method of cleaning internal surfaces of subsea drilling rig equipment and retrieving a wear bushing in a single operation.

Abstract: Well cleaning apparatus comprises a tubular body member attached to a work string which supports one or more resilient and pliable cleaning members. Each cleaning member is provided with a means for allowing bypass as sized and adapted to wipe the well casing. In one embodiment, the apparatus may be used to plunge the well with the cleaning members providing the sealing relationship with the well casing.

Abstract: A down-hole tool for use in an oil or gas well is provided with detachable components that are held to a body or tool housing by longitudinal mechanical fasteners disposed in a generally radial orientation. The mechanical fasteners allow for the components to be quickly removed and refurbished or replaced, while also permitting radial movement or floating of the components during operation of the tool. A spring may be incorporated to bias the components in a radial outward direction during operation.

Abstract: A well cleaning tool adapted for connection to a drill string for removing debris and residues from the inner wall of a well casing, comprises an elongate generally cylindrical member (1) having a plurality of scratching elements (2) in the outer surface thereof. First and second helical channels or grooves (3 and 4) are defined in the outer surface of the cylindrical member (1) between the scratching elements (2), the second helical channel or groove (4) running in the counter direction to the first helical channel or groove (3).

Abstract: A method of setting a packer in a bore comprises the steps: mounting a packer on an elongate support member; mounting a casing scraper (10) on the elongate member; running the packer and the casing scraper (10) into a bore on the elongate member to a section of the bore where the packer is to be set; cleaning the section of bore with the scraper (10); and setting the packer in the cleaned section of bore. The scraper (10) comprises: a mandrel (22) adapted for coupling to the elongate member; a sleeve (14) mounted on the mandrel (22); and a plurality of scraper members (16) on the sleeve (14), the members (16) being radially movable relative to the mandrel (22).

Abstract: The invention relates to washpipe assemblies for use in well bores and provides a washpipe assembly (2) comprising a washover shoe (10) attached to a washpipe (18), wherein a washpipe stabiliser (22) is provided on the washpipe (18) so that, when in use, deflection of the washover shoe (10) from a desired position is substantially prevented. The washpipe assembly of the present invention has the advantage over the prior art assemblies of providing means for supporting the washpipe off the wall of a well bore or well bore casing (52), and thereby reducing the torque required to rotate the washover string and the tendency of the washover shoe (10) to deviate from its preferred path down the well bore.

Abstract: Run into a well, e.g., in a tube, on a pipe string is a hydromechanical cleaner. The bridge is washed out by the direct desending flow of drilling mud pumped through the pipe string 2. The cleaner is moved downward as the bridge is washed out by moving the pipe string. Ascending flow of drilling mud rotates cleaning heads in opposite directions. Cutting knives of the cleaning heads mechanically remove deposits from the walls of tubing 1. Deposits from the walls are removed mechanically during running of the cleaner into the well and during its lifting from the well. Products of the washed out bridge and deposits are removed from the well by an ascending flow through the side branch pipe of the wellhead circulating head. The device for embodiment of the method includes also a mechanism for moving the pipe string and a pump unit.

Abstract: A downhole tool for cleaning internal surfaces of subsea drilling rig equipment, including drilling risers, blowout preventor assemblies and wellhead assemblies, as well as for retrieving wear bushings, comprising an elongated support body, at least a pair of scraper blades and wash ports. A unique method of cleaning internal surfaces of subsea drilling rig equipment and retrieving a wear bushing in a single operation.

Abstract: A cleaning tool (1) for cleaning casing within a wellbore is comprised of an upper (3) and lower (4) sleeve which are mounted via ball bearings (5) on a work string (2). The ball bearings enable the upper (3) and lower (4) sleeves to have no or negligible rotational movement notwithstanding rotation of the work string (2). The upper (3) and lower (4) sleeve limit the axial movement of the cleaning tool (1) along the work string (2). The cleaning tool (1) is further comprised of at least one lantern (6) which supports the plurality of cleaning member (7) which may be brushes or scraping blades.

Abstract: A tube cleaning article removes material from a tube in a well. A resilient member defines an encompassing path around a portion of the outer surface of the tube. The resilient member has a metallic inner surface biased toward the tube when the member is mounted on the tube such that the metallic inner surface scrapes material from the outer surface of the tube in response to reciprocating the tube relative to the resilient member. The metallic inner surface preferably presents more than two metallic edges along a longitudinal path of the outer surface of the tube. A particular implementation includes a split metallic ring. The split preferably extends at a transverse angle to the axial length of the ring. A spacer can be used with the ring. The spacer mounts on the tube such that the ring, when mounted on the tube, is between upper and lower portions of the spacer.

Abstract: A well cleaning tool for cleaning the inside walls of a well casing has at least two types of cleaning members; for example it may have a row of scraper blades and a row of brushes. The tool may also include one or more rotatable stabilizers that serve to maintain contact of the tool with the internal casing walls. The tool provides for obtaining the benefits of different types of cleaning members from a single trip into a well bore.

Abstract: A cutting bed impeller comprises a body portion and a plurality of paddles projecting outwardly from the body portion, at least one of the paddles comprising a radially outer face extending between a leading edge and a trailing edge in a normal direction of rotation of the impeller about an axis of rotation of the cutting bed impeller, a leading face, and a trailing face. The radially outer face extends between the leading face and the trailing face. The leading face is inclined at a first angle &agr; to a first tangent T1 to the radially outer face at the leading edge. The trailing face is inclined at a second angle &bgr; to a second tangent T2 to the radially outer face at the trailing edge, the second angle &bgr; being less than the first angle. The radially outer face of one or more of the paddles may be provided with one or more replaceable wear elements.

Abstract: A down hole cleaning assembly and method of cleaning a tubular. Generally, the down hole assembly is connected to a work string concentrically located within a casing string. In one embodiment, the down hole assembly comprises a mandrel operatively connected to the work string, with the mandrel having an opening therein. A pad member is received within the opening, with the pad member having a groove formed therein. Also provided is a wire brush member, operatively positioned within the groove of the pad member, for cleaning the internal diameter of the casing string. The pad member and groove may be helical, with the wire brush member positioned within the groove. The down hole assembly further comprises a biasing member, operatively positioned between the mandrel and the pad member, adapted for biasing the wire brush means against the inner diameter of the well bore.

Abstract: A downhole cleaning tool (20) is suspended within a well tubular member (10) by coiled tubing (12) for the removal of deposits (29) within the tubular member (10). Tool (20) includes a hydraulic fluid motor (26) for rotating a combined fluid jetting and milling head (28). Fluid jetting and milling head (28) has a tapered body with a lower rounded nose (60). Embedded milling inserts or elements (62, 64) project outwardly from the tapered body and nose (60) to contact the deposit and are randomly spaced on head (28). A plurality of upper radial jets (70) extend above milling elements (62). Lower fluid jets or ports (78) extend from the lower rounded nose (60) of head (28). Power fluid from the coiled tubing (12) is divided at port (38) to the rotor bore (34) into a bypass fluid stream flowing through central bore (34) and a fluid power stream in annular passage (39) outside rotor (32) for rotation of rotor (32) and shaft (27) to rotate the fluid jetting and milling head (28).

Abstract: A tool for use in a well bore has a housing attachable to a work string or drill string wherein the housing supports a floating component that is free to move in the lateral or radial members relative to the housing within predetermined limits. The floating component is suitable for supporting active tool components such as wire bristles, scraper blades or other functional apparatus. Typically, the floating component is provided as a sleeve around the housing held within axial limits, while enabling radial movement.

Abstract: A well bore cleaning tool adapted for close tolerance well bores is provided comprising a plurality of cylindrical collars attached to an elongated cable by a plurality of corresponding bent sleeves. The collars are adapted for detachable securing on a casing pipe in a vertically spaced apart relationship to each other. Each sleeve is fixedly secured within a cutout of a corresponding collar by a strip juxtaposed over an exterior surface of the sleeve, opposing ends of the strip extending beyond the cutout for attachment to the corresponding collar, such that a minimal portion of the sleeve extends beyond an outside diameter of the collar. The elongated cable is threaded through the sleeves of the collars such that the cable extends along and in close proximity to the casing pipe, to thereby facilitate cleaning of a well bore in close tolerance conditions.

Abstract: A method of cleaning the casing string comprises lowering the drill string with a cleaning apparatus thereon. The cleaning apparatus includes a mandrel, a wire brush member located in an opening in the mandrel, a spring, and a centralizer. The method includes urging the wire brush member against the inner diameter of the casing string and cleaning the inner diameter of the work string. Also, the casing string may have a highly deviated section so that a low side and a high side of the casing string is created. The method includes lifting the apparatus from the low side the inner diameter of the casing string with the centralizer and urging the wire brush member against the low side and the high side of the casing string with the spring.

Abstract: A cutting bed impeller (10) comprises a body portion and a plurality of paddles (24) projecting from the body portion, one or more of the paddles (24) having a recess (18) on its leading face in the direction of rotation of the impeller (10). The radially outer face (26) of one or more of the paddles (24) may be provided with one or more replaceable wear elements (30, 38). For example the elements may comprise nylon inserts (30) fitted into openings (28) in the radially outer faces (26) of the paddles (24).

Abstract: A down hole cleaning assembly is connected to a work string concentrically located within a casing string. In one embodiment, the down hole assembly comprises a mandrel operatively connected to the work string, with the mandrel having an opening therein. A pad member is received within the opening, with the pad member having a groove formed therein. Also provided is a wire brush member, operatively positioned within the groove of the pad member, for cleaning the internal diameter of the casing string. The down hole assembly further comprises a biasing member, operatively positioned between the mandrel and the pad member, adapted for biasing the wire brush against the inner diameter of the well bore. In the preferred embodiment, the wire brush includes a wire bundle, a brace disposed about the second end of the wire bundle, and wherein the brace is disposed within the groove of the pad member.

Abstract: A tool for the cleaning and conditioning of tubular structures, such as well casings, comprises a central mandrel (1) upon which are mounted a plurality of interchangeable sleeves (4-9). The sleeves at each end bear stabilization elements enabling the tool to be used in a well casing of any disposition and the intermediate sleeves bear conditioning or cleaning elements (12) angularly spaced apart and separated by fluid channels (13), the cleaning elements of adjacent sleeves being off-set to form a substantially helical pattern of cleaning elements and channels to ensure 360.degree. of coverage as a tool is axially displaced within a well casing. The sleeves are mounted in such a way that relative rotation between them and the mandrel is prevented by a combination of keyways and of drive faces between adjacent sleeves formed by cut-away portions.

Abstract: An apparatus for cleaning the interior of a well tubing, comprising a body member (10) for insertion into the tubing, and at least one cleaning pad (14) mounted on the body member (10), the or each cleaning pad (14) comprising a body having an inner face engaged with the body member (10) and an outer face provided with protruding bristles (38). The apparatus further comprises protection pads (50) mounted on the body member (10).

Abstract: An apparatus and method for cementing a pipe in a well. A wiper is engaged with a pipe section as the pipe section is lowered into the wellbore. The wiper contacts the wellbore as the pipe section is reciprocated or rotated within the wiper. The wiper contacts and cleans the exterior surface of the pipe section as the pipe section is moved relative to the wiper. By cleaning the exterior of the pipe section before cement is placed between the pipe section and the wellbore, the potential for channeling in the microannulus between the pipe section exterior and the cement is substantially reduced.

Abstract: A cleaning tool for tubular members has a pattern of scratching elements arranged on the outside of an elongate member such as a mandrel. The mandrel is coated with a rigid or resilient polymeric material or a combination of both. The scratching elements are affixed in the polymeric material in an arrangement to allow fluid flow around the mandrel.

Abstract: A tool for cleaning oil, gas, and water well wall casing is disclosed. The cleaning tool includes a cylindrical member and a helical swath of scratching elements affixed to the side walls of the cylindrical member positioned for scouring the interior wall of the casing. Also included in the side walls of the cylindrical member is a helical channel adjacent to the swath of scratching elements. Typically, a workstring maneuvers the tool through the casing under mechanical force. Fluid is circulated through the channel of the tool to carry to the surface the loosened debris scoured from the interior wall of the casing. A method of cleaning a well casing is also disclosed. The method includes the use of a tool with scratching elements and flow channels, which tool can be used either with or without cleaning solvents.

Abstract: A device comprises cleaning heads 4,5 mounted on a shaft for free rotation. On sinking and elevating the device on a tractive member, in a liquid up-current, the heads start rotating in different sides. Cutting elements--knives--having an involute profile and arranged on oppositely directed spiral paths cut the deposits. On descent, cutting collars of said knives situated in the lower portion on head perform "rough" cutting, the knives of both heads crush the cuts and chips, and cutting collars in the upper portion of the upper head carry out the "finishing" of the internal surface of an uptake pipe. The given mathematical relations defining the ratio of parameters of the device elements are as follows: the heights of heads and an angle of attack of knives, the lengths of the shaft and a stabilizer, their mass, the length of the pitch of knives and the diameter of the heads.

Abstract: A combination clean-out and fishing tool for use under rotary power in a well bore. The tool is adapted for connection to the drill string by means of an elongated connector sub. The connector sub then carries a cylindrical sleeve thereon which houses a cylindrical hub secured within the sleeve by means of shear pins. A cylindrical extension then secures below the cylindrical sleeve to support a clean-out tool of selected type therebelow while the hub and extension sub carrying a selected fishing tool are inside the cylindrical extension. After rotary operation of the clean-out tool to expose the fish, sufficient weight jarring the drill stem shears the shear pins to lower the connector sub, hub, extension sub and fishing tool into rotary engagement with the fish.

Abstract: A combination scratcher-centralizer for use in installing casing in wellbores comprising a single piece of coiled wire or rod having a first hub part for tightly engaging the casing, a radially expanded centralizer and scratcher portion forming a helical wrap of said wire and a second hub part slidable on the casing and formed by a helical wrap of said wire. The first hub part includes serrations and/or a plurality of retaining screws provided so that the first hub part may be secured to the casing in a predetermined position to allow the expanded centralizer coil or wrap portion to undergo some elastic axial excursion during its scratching and scraping operation upon installation in a wellbore. The constricted hub part may be held in a radially expanded position during installation by a retainer engageable with spaced apart portions of the wraps of the hub part.

Abstract: A well cleaning attachment useful as a part of a collection of tools sent down a well bore on a tubing string includes a tubular mandrel provided with a plurality of longitudinal slots in which corresponding knife carriers are inserted. Each carrier is bedded on a leaf spring for radial motion within the slot and each is provided with a spring biased blade extending pivotally to the exterior. Two collars then fix the carriers within the slots, the same collars also engaging the periphery of the mandrel.

Abstract: A swab assembly for use within a pump barrel includes a longitudinal swab bypass mandrel which has a top end connectable to a reciprocating member and at least one longitudinal bypass channel on its circumference and axially spaced stop shoulders at each end of the bypass channel with a smooth sealing portion between the bottom end of the bypass channel and the lower stop shoulder. At least one swab cup is slidable vertically on the bypass mandrel between an uppermost fluid bypass position and a lowermost fluid lifting position. The swab cup has a generally cylindrical outer body formed of flexible resilient material surrounding a tubular metal sleeve and has a central longitudinal bore coaxial with the bore of the sleeve. The cup body has an upper portion extending beyond the top end of the sleeve and a lower portion extending below the bottom end of the sleeve.

Abstract: A clean-out tool system for use with a oil well production tubing extending downward through a casing terminating in a production zone in the well bore, which zone is isolated by a packer and includes flow restricting debris to be cleaned out. A generally vertical, elongated, cylindrical tool body, having a relatively small diameter and a bore therein, is located down through the inner production tubing into the zone located at the end of a tubing string extending downward through the production tubing for communicating fluid pressure to the bore in the body. Four, peripherally spaced, elongated slots extend radially inward into the body with their longitudinal axes aligned with the longitudinal axis of the body and communicate with the bore is the body. An elongated blade is pivotally attached in each slot to the body, movable from a first configuration wherein the blade is positioned vertically within the slot, and a second, expanded configuration positioned radially outward in the zone.

Abstract: A drilling tool which is suitable especially for clearing drill dust from a drillhole in rock-drilling work is provided. For this purpose, the spiral shank has brush elements (6, 17) which are arranged in the groove bottom of a conventional drilling tool or which themselves form spiral feed coils.

Abstract: A casing scraper is provided for scraping foreign materials from the inside of pipe casing and other tubular members. The casing scraper is comprised of a central mandrel supporting a plurality of longitudinally and circumferentially extending scraper blades, the collective configuration of the scraper blades comprising a tube structure with the mandrel located at the longitudinal axis of the tube structure. Connecting links attach the mandrel to the plurality of scraper blades. Said connecting links are each pivotally attached to the mandrel and to the scraper blades. An adjustable spring is provided at the base of the mandrel and biased against the underside of the connecting links normally biasing said connecting links at a right angle to the axis of the mandrel, thereby normally positioning the scraper blades at the maximum distance from the mandrel allowed by the length of the connecting links.

Abstract: Nozzle-effect well apparatuses including nozzle-effect protectors, centralizers and stabilizers and related methods, the apparatuses having two or more blades or ribs extending outwardly from a body, the blades or ribs spaced apart further at one end of the apparatus than the other; in one embodiment, the wall thickness of the apparatus varying so that one end is thicker than the other or a portion or portions between the ends are thicker or thinner in wall thickness than other portions; in another embodiment, portions of valley areas between ribs or blades varying in size to create nozzle effects.

Abstract: A well clean-out tool comprising a ported nipple, thimble, packer cup, packer cup mandrel and an inner mandrel.

Abstract: The invention provides a method and apparatus for securement onto one end of a continuous length of remedial tubing which is introduced into a subterranean well concentrically through production tubing previously positioned within the well, with the well having a deviated configuration which includes an entry portion communicating with a curved portion extending downwardly in the well from the entry portion and a generally linear end portion traversable with a production formation. The apparatus includes a cylindrical housing and an element for securement of the housing to the tubing. A fluid passageway chamber is defined exterior of the housing with fluid passageways communicating between the interior of the housing and the expansion chamber. Turbulating elements are carried exteriorly around the housing and immediate the expansion chamber and are freely rotatable relative to the housing.

Abstract: An apparatus for use in energy exploration is disclosed which is used where a radially expanding device is required, for example in a stabilizer, retriever or an underreamer. The apparatus comprises a support tubular member for connection to a drilling string, the member supporting a movable member which is axially movable along the member. A further member which may either be fixedly secured or also axially movable along the member is axially spaced from the movable member. The movable member and, optionally, the further member have tapered outer surfaces which cooperate with a taper on a radially movable member. The arrangement is such that movement of the movable member in the axial direction is such that the cooperating tapers cause the radially movable member to expand or contact in the radial direction. Various means for securing and performing radial movement are disclosed.

Abstract: A clean-out tool system for use with a oil well production tubing extending downward through a casing terminating in a production zone in the well bore, which zone is isolated by a packer and includes flow restricting debris to be cleaned out. A generally vertical, elongated, cylindrical tool body, having a relatively small diameter and a bore therein, is located down through the inner production tubing into the zone located at the end of a tubing string extending downward through the production tubing for communicating fluid pressure to the bore in the body. Four, peripherally spaced, elongated slots extend radially inward into the body with their longitudinal axes aligned with the longitudinal axis of the body and communicate with the bore in the body. An elongated blade is pivotally attached in each slot to the body, movable from a first configuration wherein the blade is positioned vertically within the slot, and a second, expanded configuration positioned radially outward in the zone.

Abstract: An arrangement for cleaning the internal surface of casing strings, comprises a hollow cylindrical body with slots provided around the periphery thereof. The slots accommodate extendable cutting blades. The cutting blades are moved with the aid of walls of an elastic vessel. The elastic vessel is disposed inside the body and adapted to be communicated with a source of compressed fluid medium. The elastic vessel is disposed in a bushing installed coaxially with the body and provided with longitudinal ports. The ports are arranged opposite to the slots of the body and are equipped with flat spring elements. The flat spring elements substantially completely cover the ports of the bushing and cooperate by one side with the cutting blades and by the other side, with the elastic vessel.

Abstract: A scraper for pipe is provided with scraper blades having arcuate scraper surfaces projecting therefrom with the blades movable radially between a contracted and expanded position which provides a first minimum diameter of the scraper surfaces in contracted position and a second maximum diameter when in expanded position which extends at least to the maximum internal pipe diameter, and an adjustment arrangement which enables said arcuate scraper blades to be adjusted radially to maintain said first and second diameters as the scraper surfaces wear.

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

Abstract: A well bore cleaning tool comprises a plurality of collars which slip onto a pipe casing without welding, and can be securedly attached thereto using any conventional securing means, such as set screws. The collars are interconnected with a cable, disposed longitudinally on one side of the casing, substantially in a straight line. The well bore cleaning tool has utility in bore holes wherein there is a limited clearance or amount of space in the annulus (that is, the region between the exterior of the casing and the wall of the bore hole).

Abstract: Method and apparatus for cleaning out a cased or uncased wellbore (particularly a high angle wellbore) prior to running a(nother) string of casing, a logging tool, or the like, into the hole. A stiff-bristled scouring brush is run in the hole on the leading end of a drill string. The brush is rotated as it is advanced through the portion to be cleaned to enhance dislodgement of caked on cuttings, drilling mud, and the like. Drilling fluid is reverse-circulated down the casing to entrain the dislodged material and carry it uphole in the high-velocity stream inside the drill string. A centering dolly keeps the apparatus positioned in the wellbore and keeps the weight of the drill string from riding on the brush.

Abstract: A device for scraping the inside of pipes clogged with foreign materials is comprised of (1) a mandrel having a conical cam whose top is attached to a mechanical power source and around which is mounted (2) a plurality of annularly expandable scraper elements whose combined outside configuration approximates a tube which can be inserted into the pipe, and whose combined inside configuration approximates an expandable, conical dome into which the mandrel's conical cam is pulled in order to annularly expand the elements of the conical dome and hence expand the plurality of scraper elements as the entire device is pulled through the pipe and (3) means for limiting the annular expansion of the scraper elements.