Abstract: In a threaded joint for steel pipes which are connected by threaded engagement of a pin member having a tapered male thread, a metal seal-forming portion, and a torque shoulder-forming portion on the end of a pipe, and a box member having a tapered female thread, a metal seal-forming portion, and a torque shoulder forming-portion corresponding to these on the end of a pipe, a buttress thread having contact at the load flanks and the thread root surface and gaps at the thread crest surface and the stabbing flanks is mixed in a single joint with a rugged thread having contact at the load flanks and stabbing flanks and having gaps at the thread root surface and thread crest surface.

Abstract: A connector part (3) for connecting a material supply device (10) to a spray gun (20) that includes a hollow cylindrical connection piece (5); a threaded wedge element (8) with a lower starting point (8a) and an upper end (8b) running around the outer circumference of connection piece (5) and serving to produce a threaded wedge connection to a counter-element (15) arranged on gun base (19) of spray gun (20); and a stop element (14) that forms a limit stop during the production of the threaded wedge connection. In order to prevent the counter-element on the spray gun from digging into the soft connection pipe made of plastic and removing plastic chips there, it is provided in the connector part according to the invention that stop element (14) is arranged at a distance in the circumferential direction from upper end (8b) of threaded wedge element (8), whereby a gap (11) is formed between stop element (14) and upper end (8b) of the threaded wedge element.

Abstract: A threaded connection includes a first tubular, a second tubular, and a coupling. The first and second tubulars include external threads, a pin nose, a pin nose surface, a pin shoulder surface, and a pin seal surface located between the pin nose and pin shoulder surfaces. The coupling includes two internal threads corresponding to the external threads of the first and second tubulars and an inner seal support. Upon selected make-up, the pin noses overlap and contact occurs between the pin nose seal surfaces and the inner seal support is in an overlapping axial position with respect to the pin noses such that a diametrical gap exists therebetween.

Abstract: A threaded connection for a conduit includes a pin member and a box member. The pin member includes a pin thread having a pin thread crest, a pin thread root, a pin load flank oriented at a pin load flank angle, and a pin stab flank oriented at a pin stab flank angle. The box member includes a box thread having a box thread crest, a box thread root, a box load flank oriented at a box load flank angle, and a box stab flank oriented at a box stab flank angle. At least one of the pin load flank angle, the pin stab flank angle, the box load flank angle, and the box stab flank angle varies over at least part of the threaded connection.

Abstract: A submersible pump drop pipe and casing assembly and method of manufacture is disclosed. The drop pipe/casing has a seated connector and base. The seated connector has a first and second cylinder section, the first cylinder section being used to align and direct the base into the seated connector and to provide lateral strength to the pipe.

Abstract: A threaded connection includes a male member having threads thereon defining a load flank lead and a stab flank lead. The threaded connection also includes a female member having threads thereon adapted to mate with threads on the male member, wherein the threads on the female end define a load flank lead and a stab flank lead, wherein at least one of the load flank lead and the stab flank lead on at least one of the female member and the male member change at a predetermined rate beginning at a selected distance from either one or both ends of the threads, wherein the stab flank lead and the load flank lead are different from each other over at least part of the thread length.

Abstract: A threaded connection includes an externally threaded pin connection and an internally threaded box connection. The pin connection has a proximate end, a distal end, a pin shoulder at the proximate end and a distal contact surface at the distal end. The box connection has a proximate end, a distal end, an internal contact surface at the proximate end and an external shoulder at the distal end. At least one deformable element is positioned either between the pin shoulder of the pin connection and the external shoulder of the box connection or between the distal contact surface of the pin connection and the internal contact surface of the box connection. The deformable element is of a softer material than that of the pin connection and the box connection, such that the deformable element deforms in response to a momentary torque overload.

Abstract: A threaded oilfield tubular connection includes a box connector 12 having internal threads 16, 18, and a pin connector 14 having external threads 22, 24 for mating with the internal threads. Each of a box torque shoulder 20 and a pin torque shoulder 26 may be negative angle shoulders, and the thread flanks on the internal and external threads may also be negative angle load flanks. The connector substantially maintains a desired preload when dope is trapped between the threads during makeup. Another embodiment provides positive angle torque shoulders and positive angle load flanks.

Abstract: A threaded connection including a pin member and a box member, and methods for manufacturing and forming said threaded connection. The pin member has a pin thread with a pin thread crest, a pin thread root, a pin load flank, and a pin stab flank. The box member has a box thread with a box thread crest, a box thread root, a box load flank, and a box stab flank. At least one of the pin thread crest, the pin load flank, the pin stab flank, the box thread crest, the box load flank, and the box stab flank has at least one perturbation formed thereon. Upon a selected make-up of the pin member with the box member, an increased contact stress exists between the pin thread and the box thread at the at least one perturbation.

Abstract: A thread form having improved strength and fatigue resistance. The root of the thread may be cut on multiple cutting radii having displaced centers. At least two of the root surfaces formed by cutting radii may have lengths that are greater than the root truncation. The threads may be used in a double start configuration to increase the connection strength and reduce makeup and breakout rotations.

Abstract: An expandable threaded connection between segments of expandable tubulars. The present invention utilizes two complementary thread segments. The first segment of the threaded connection utilizes standard box and pin threads. In the second segment of the threaded connection, material is removed from the stab flank of the pin threads to reduce the standard width of the pin threads, while the box threads of the second segment are standard thread width. The use of the reduced thread width in the pin threads of the second segment allows for a loose fit between the pin threads of the second segment and the box threads of the second segment. The loose fit between the pin and box threads of the second segment allows radial and axial movement between those threads without causing disengagement of the threaded connection during the expansion process.

Abstract: A screw connection comprising a wire thread insert 8 which is inserted between a female thread M of a workpiece 4 and a male thread B of a screw 6 and which consists of a helically coiled wire thread member having a male thread adjacent internal thread 10 and a female thread adjacent external thread 12, characterized in that the profile angles ?B, ?M of the internal and external threads 10, 12 of the wire thread insert 8 are smaller than the respective profile angles ?B, ?M of the male thread B and, respectively, the female thread M such that when the screw connection is loaded by a predetermined biasing force KV the load flanks of the internal and external threads 10, 12 of the wire thread insert 8 engage the associated load flanks of the male and female threads B, M in full contact relationship.

Abstract: A thread form is shown which is used to make a threaded pipe connection capable of being screwed together and subsequently unscrewed. A pin member is provided having external threads with stab flanks and load flanks and flat crests and roots for mating with the mating internal threads of a box member to make up a pipe connection. One of the stab or load flanks is made up of two facets and three radii. The other selected flank is made up of three facets and four radii, giving it irregular features forming a complex geometric profiles. The thread form can be used to form a premium threaded connection which is used with such tubulars as casing and tubing for oil, gas, water and waste disposal wells.

Abstract: A tubular connection having a first joint having outer threads and an inner bore, and a second joint having outer threads and an inner bore. The tubular connection further includes an outer nut having inner threads that cooperate with the outer threads of the first joint and the second joint. The tubular connection further includes an inner sleeve positioned within the first inner bore and the second inner bore. In one embodiment, the first inner bore contains a first groove having first seal disposed therein and the second inner bore contains a second groove having second seal disposed therein, wherein the first and second seal prevents a pressure from exiting the first and second inner bore.

Abstract: An elongated drive string assembly comprising a plurality of hollow sucker rods and connecting elements with an axis, connected together and between a drive head located at the surface of an oil well and a rotary pump located deep down hole in an oil well. Each hollow sucker rod has at least a first end comprising an internal female threaded surface engaging an external male threaded surface on a connecting element, such as a nipple. In order to further optimize the stress distribution between the elements, frustro-conical, non-symmetrical threads with a differential diametral taper are used. Preferably two torque shoulders with a maximized mean diameter and cross-sectional area are used to resist storing reactive torque in the drive string. The nipple free end defines a second torque shoulder that adds to the torque transmission during make-up while also defining a small seal at that free end to decrease corrosion erosion problems.

Abstract: A drill string comprises a first drill string member having a male end; and a second drill string member having a female end configured to be joined to the male end of the first drill string member, the male end having a threaded portion including generally square threads, the male end having a non-threaded extension portion coaxial with the threaded portion, and the male end further having a bearing surface, the female end having a female threaded portion having corresponding female threads, the female end having a non-threaded extension portion coaxial with the female threaded portion, and the female end having a bearing surface. Installation methods, including methods of installing instrumented probes are also provided.

Abstract: A submersible pump drop pipe and casing assembly and method of manufacture is disclosed. The drop pipe/casing has a seated connector and base. The seated connector has a first and second sections, the first section being used to align and direct the base into the seated connector and to provide lateral strength to the pipe.

Abstract: A threaded joint for steel pipes comprised of a pin 1 and a box 2 each having a threaded portion (1a, 2a) and an unthreaded metal contact portion (1b, 2b) exhibits adequate leakage resistance and galling resistance when used for makeup of oil country tubular goods with application of a green dope or even without any dope. The threaded joint has a first plating layer of Sn—Bi alloy plating or Sn—Bi—Cu alloy plating formed on the contact surface of at least one of the pin 1 and the box 2. The first plating layer may have a second plating layer selected from Sn plating, Cu plating, and Ni plating on its lower side and at least one layer of a lubricating coating, and particularly a solid lubricating coating, on its upper side.

Abstract: A thread form having improved strength and fatigue resistance. The root of the thread is cut on multiple cutting radii having displaced centers. At least two of the root surfaces are formed by cutting radii having lengths that are greater than the root truncation. The threads are used in a double start configuration to increase the connection strength and reduce makeup and breakout rotations.

Abstract: There is provided a screw joint for oil well tubing, excellent in seal performance and having a high maintainability. A screw joint for oil well tubing comprising a male screw tube equipped with a seal forming portion having a convex curved surface shape on a tip end portion of the tube and a female screw tube equipped with a tapered seal portion, wherein when the convex curved surface shape comes into contact with the tapered seal portion, a contact surface pressure Pc60 equivalent to 60% of a maximum contact surface pressure Pcmax applied to a contact surface is larger than an inner pressure Pi applied to the screw joint and is smaller than a proportional limit or of a screw joint material, wherein a taper angle ?s of the tapered seal portion and an angle ?t of a tapered screw satisfy a formula ?s??t, and curvature radius R of the convex curved surface shape is not smaller than 90 mm and not larger than 170 mm, wherein the angle ?s is from 1.4 degree to 9.

Abstract: Expandable tubing and methods seal a connection between expandable tubulars, and in particular, seal a connection between expandable tubulars post-expansion. In one embodiment, a method includes sealing a connection between expandable tubulars in the form of sections of an expandable liner. The method comprises the steps of connecting a first expandable tubular in the form of a first section of the liner and a second expandable tubular in the form of a second section of the liner. A seal is located between radially overlapping portions of the liner sections, and the seal is configured to maintain sealing between the liner sections both pre and post expansion.

Abstract: Tubular connections and methods of designing tubular connections having selected root/crest clearance when the box member and pin member are made-up. When the tubular connection is radially expanded, a thread seal is formed over at least part of the tubular connection.

Abstract: A threaded joint for steel pipes comprising a pin 1 and a box 2 each having a contact surface comprising a threaded portion 3 or 4 and an unthreaded metal contact portion 8 is provided with improved anti-galling propertied by forming a lubricating coating on the contact surface of at least one of the pin and the box, the lubricating coating exhibiting a self-repairing function by liquid lubrication and having a decreased greasiness. The lubricating coating is (1) a coating which comprises a lower lubricant layer which is in liquid form in the temperature range of above 0° C. and below 40° C. and an upper lubricant layer which is in solid form at 40° C., or (2) a coating which is semi-solid or solid at 40° C. and is formed of a mixture comprising a lubricating oil which is in liquid form in the temperature range of above 0° C. and below 40° C. and a wax which is in solid form at 40° C., the mixture preferably having been heated so as to liquefy the wax and dissolve in each other the wax and lubricant oil.

Abstract: Lubricant escape passages are formed in the threads used to connect one tubular body to another. The passages conduct trapped thread lubricant out of the threaded area to prevent the creation of high lubricant pressure that may damage or cause improper make up of the threaded connection. The passages may be grooves in the crests of the thread teeth and/or may be corner bevels on the thread teeth. In a conductor pipe or other pipe assembly using axially spaced internal and external seals at each axial end of the threaded area, the escape passages form a helical flow path through the engaged thread area. The external seal prevents the entry of corrosive fluids into the threaded area and the internal seal prevents leakage through the threaded area from within the conductor pipe. When the lubricant pressure increases excessively during assembly or impact loading of the connection, the lubricant escapes past the seals to prevent connection damage.

Abstract: A thread form is shown which is used to make a threaded pipe connection capable of being screwed together and subsequently unscrewed. A pin is provided having external threads with stab flanks and load flanks and flat crests and roots for mating with the mating internal threads of a box to make up a pipe connection. The stab flanks and load flanks form complex geometric profiles which in one version form an inclined Z-shape in profile and in another version form a reverse inclined Z-shape profile. Each profile includes at least three separate facets with the facets on the stab flank and the facets on the load flank both leaning in the same direction with respect to the longitudinal axis of the pipe, when viewed in profile.

Abstract: A threaded connection between adjacent tubular members includes a pin member providing an external wedge thread and a box member providing an internal wedge thread, wherein the internal wedge thread corresponds with the external wedge thread. Further, the threaded connection includes at least one interruption along a helical thread length of one of the external wedge thread and the internal wedge thread and at least two regions along an axial length of the threaded connection where the external wedge thread and the internal wedge thread form a thread seal.

Abstract: A threaded tubular connection includes two elements, male and female, made up one into the other to a given torque in which, prior to making up, at least one thread face under contact pressure has a convexly rounded shape that is continuous over its width with a radius of curvature in the range 2 to 60 mm and is in point contact with the corresponding face of the mating element. Such a threaded connection has an increased resistance to breakout or to overtorquing. In one embodiment, the convexly rounded face is a male or female thread flank and one of the male or female threads includes a groove opening into the thread crest to render flexible either the convexly rounded flank or the corresponding flank. Such a geometry can accommodate variations in contact between the flanks.

Abstract: A method to improve fatigue resistance of a threaded tubular connection. Radial interference between a male and female threading operates between stabbing flanks inclined at about 27° with respect to an axis of the threadings, wherein mutual contacting surfaces are radially spaced from a root of the male threading, which is defined by a concave rounded portion. Thus, micro-cracks caused by friction between these surfaces during relative movements of the male and female threaded elements are not affected by tensile stresses moving along an envelope of the male thread root, improving fatigue resistance of the connection. Such a method may find particular application to hydrocarbon wells connected to offshore platforms.

Abstract: An expandable coupling arrangement for coupling first and second tubulars includes a male thread portion on an end of the first tubular and a female thread portion on an end of the second tubular. The thread portions comprise dovetail threads having flanks, roots and crests, wherein the flanks are inclined at an angle of greater than 10°.

Abstract: A submersible pump drop pipe and casing assembly and method of manufacture is disclosed. The drop pipe/casing has a seated connector and base. The seated connector has a first and second cylinder section, the first cylinder section being used to align and direct the base into the seated connector and to provide lateral strength to the pipe.

Abstract: A threaded tube joint for oil extraction industry has a trapezoidal thread and a toroidal sealing surface (11) placed at its end near the thread and engages, for sealing, a corresponding frusto-conical sealing surface (12) wherein the toroidal sealing surface (11) has a radius Rs value comprised within the range given by the formula E 2 ? Vo ? ( b 2.15 ) 2 ? Rs ? ? · E 2 ? tn n 3 ? OD 2 240 ? ? ? · ? ad 2 ? wt 2 ? ( 1 - ? 2 ) ? [ 3 ? ( 1 - ? 2 ) R n 2 ? tn 2 ] 3 / 4 .

Abstract: A threaded connection includes a continuous pin thread including at least a first step, a mid-step, and a second step formed sequentially thereon. A continuous box thread includes at least a first step, a mid-step, and a second step formed sequentially thereon, wherein the steps on the box thread correspond generally in axial position with the steps on the pin thread. The first step has a first wedge ratio, the mid-step has a transition wedge ratio, and the second step has a second wedge ratio, wherein thread leads are substantially constant within each of the steps. The connection is designed such that at make-up of a pin member with a box member, a clearance exists between at least one of corresponding load flanks and corresponding stab flanks on at least one of the first step, the mid-step, and the second step.

Abstract: A tubing connection arrangement and a method used for coupling expandable tubing sections together. In one embodiment, there is disclosed a tubing connection arrangement comprising a first expandable tubing section defining a male portion; a second expandable tubing section defining a female portion, the first and second expandable tubing sections being engageable with one another; one of the first and second expandable tubing sections including a restraining member for restraining part of the other expandable tubing section; and the first expandable tubing section including a tapered shoulder for co-operating with a corresponding tapered shoulder of the second expandable tubing section.

Abstract: A drill string comprises a first drill string member having a male end; and a second drill string member having a female end configured to be joined to the male end of the first drill string member, the male end having a threaded portion including generally square threads, the male end having a non-threaded extension portion coaxial with the threaded portion, and the male end further having a bearing surface, the female end having a female threaded portion having corresponding female threads, the female end having a non-threaded extension portion coaxial with the female threaded portion, and the female end having a bearing surface. Installation methods, including methods of installing instrumented probes are also provided.

Abstract: Pipe integral threaded joint formed by a male element (1) and a female element (2) respectively placed on the external surface and on the internal surface of two truncated cone-shaped parts of the threading (6, 7, 8, 9) having the same conicity value and being radially spaced, both being respectively divided by annular shoulders (5, 5?) which are parallel and orthogonal with respect to the pipe axis. They are provided two sealing surfaces (12, 12?, 13, 13?), one of them being cone-shaped and the other being spherical. After the screwing of the two elements (1, 2) said two annular shoulders (5, 5?) are in contact. Each male (1) and female (2) element comprises, respectively along its external and internal surface, a circumference cavity (14, 15) placed between a part of the threading and the annular shoulder (5, 5?) in order to allow the expansion of the lubricating fat.

Abstract: An expandable tubular coupling comprises a threaded male portion and a corresponding threaded female portion, wherein the thread portions feature thread profiles configured such that the coupling may be made up to a predetermined extent, and once made up to the predetermined extent be made up no further. In a disclosed embodiment the thread profiles are a combination of a square thread profile and dovetail thread profile.

Abstract: A flush-type integral threaded joint with truncated-cone threads, with two scaling surfaces 11?, 12?, 11?, 12?) set at the end of the threaded portions (7, 8), and with two annular scaling shoulders (5?, 6?, 5?, 6?). The two threaded portions (7, 8) of the male element (1) and female element (2), respectively, have the same value of conicity, and the two sealing surfaces (11?, 12?, 11?, 12?) are, in one case, conical or cylindrical, and in the other spherical. The threaded portion of each male and female element may have an end area with a thread that is not perfect.

Abstract: A threaded pipe connection includes a box member, a pin member and a wear indicator for the connection. The pin member has internal threads and the box member has external threads. The internal threads of the box member each increase in width in one direction, while the external threads of the pin member increase in width in the other direction so that the complementary internal and external threads move into engagement upon make-up of the connection.

Abstract: A threaded pin and box connection having thread geometries and/or dissimilar thread fits that prevent the pin thread of a connection from hanging up in the box thread as the pin is being stabbed into or destabbed from the box. Dissimilar geometries and/or threads include dissimilar thread types, dissimilar leads, overlapping leads, thread tooth widths of one component greater than thread grooves of the other component, multiple start threads, and combinations thereof.

Abstract: An elongated drive string assembly includes a plurality of hollow sucker rods and connecting elements between a drive head located at the surface of an oil well and a rotary pump located deep down in an oil well, with a series of holes at each end to substantially increase the flow of extracted fluid. Each hollow sucker rod has a first end with a torque shoulder, which engages a torque shoulder formed on a connecting element. The threads are frusto-conical, non-symmetrical threads with a differential diametral taper. The torque shoulders have a maximized mean diameter and cross-sectional area to resist storing reactive torque in the drive string.

Abstract: A threaded connection for a conduit is disclosed. The connection includes a male member having threads on it defining a load flank lead, a stab flank lead and a nominal lead. A female member has threads thereon adapted to mate with the threads on the male member. The threads on the female member define a load flank lead, a stab flank lead and a nominal lead. At least one of the load flank lead and the stab flank lead, on at least one of the female member and the male member, is changed at a predetermined rate beginning at a selected distance from an end of the threads. The load lead and the stab lead are different from each other over at least part of the thread length.

Abstract: A threaded joint which economically imparts effective sealing properties to a metal-to-metal seal portion and which can prevent seizing at the time of make-up comprises a steel pipe 1 having at its tip a male thread 1b and an unthreaded sealing surface 1a, and a coupling 2 having on its inner surface a female thread 2b and an unthreaded sealing surface 2a. With the yield pressure of the inner surface of the pipe being Py, (1) the average pressure Pm of the annular contact portion satisfies Pm/Py?3, and the width in the axial direction of the portion which receives a pressure Ps which satisfies Ps/Py?1 in the annular contact portion is at least 1 mm (or at least 2 mm), and the surface roughness Ry of both unthreaded sealing surfaces is at most 25 ?m (or at most 30 ?m), or (2) the relationship between the average pressure Pm of the annular contact portion and the surface roughness Ry (?m) of the unthreaded sealing surface satisfies Pm/Py?0.0032×Ry2+1.

Abstract: Threaded pipe joint comprising a male element (1) and a female element (2), threaded and provided with respective complementary sealing surfaces, which define, when screwed together, a notch (13) formed on the female element (2) of a predetermined length (X), and a space (7, 8) between the threads of predetermined section (S), forming reservoir to house the joint lubricant, which comes out of the volume between the threads of the female (2) and male (1) elements during the tightening of the joint.

Abstract: Lubricant escape passages are formed in the threads used to connect one tubular body to another. The passages conduct trapped thread lubricant out of the threaded area to prevent the creation of high lubricant pressure that may damage or cause improper make up of the threaded connection. The passages may be grooves in the crests of the thread teeth and/or may be corner bevels on the thread teeth. In a conductor pipe or other pipe assembly using axially spaced internal and external seals at each axial end of the threaded area, the escape passages form a helical flow path through the engaged thread area. The external seal prevents the entry of corrosive fluids into the threaded area and the internal seal prevents leakage through the threaded area from within the conductor pipe. When the lubricant pressure increases excessively during assembly or impact loading of the connection, the lubricant escapes past the seals to prevent connection damage.

Abstract: A coupled version of a threaded connection 10 includes first threads 16, 38 and second threads, 20, 34 on both elongate tubulars 14, 30 and a coupling 45. An integral joint version 50 preferably includes a first and second tapered threads 58, 60 on each of the connected tubular bodies 54, 56. The coupling preferably includes a dope entrapment cavity in one of the connected tubulars between the first and second threads. A tapered metal seal surface is provided preferably between the first and second threads. The second thread in a preferred embodiment is a hook thread with a negative rake angle. In another embodiment, the pin ends of a coupled connection may engage, with seals provided between the first and second threads on each tubular.

Abstract: The threaded connection between the pin and the box ends of two pipes is sealed externally and internally to protect the threads in the connection from exposure to corrosive fluids. Seals are provided at each axial end of the threads. External seals are formed by metal-to-metal engagement between the pin and box and a third metal body secured circumferentially about the pin. The metal body may be fashioned into a desired annular pin seal surface to mate with and seal with the box at full makeup of the connection. The metal body can be removed and replaced as required to repair or reconstructed the pin seal surface.

Abstract: A threaded pin and box pipe connection having makeup shoulders that contact when the pin and box threads are fully engaged. Upon initial engagement of the shoulders, load flanks of the pin and box threads furthest from the makeup shoulders engage each other and begin progressively separating from each other by an increasing amount along the length of the engaged threads in a direction from the end of the pin to a gauge point of the connection. Upon application of the makeup torque, the separation between the load flanks distributes the torque forces between the makeup shoulders along the length of the engaged threads to prevent concentration of stress forces near the base of the pin thread. The progressive separation of the load flanks is achieved by progressively changing the pitch of the load flank of the pin and/or box thread to vary the thread width. The separation of load flanks is achieved without modifications of the stab flank pitch.

Abstract: The premium threaded tubular connection comprises, on at least one threaded element, a distal abutment surface (7) at the free end of a threaded element and a lip sealing surface (5) at a given distance from the threading.

Abstract: A threaded pipe connection is shown which features a cylindrical metal-to-metal containment seal. In addition to the cylindrical sealing surfaces, the connection utilizes a separate ramp or ramp regions that simulate a pin swaging or a box expansion which results in the ability of the cylindrical components of the seal to assemble without interference or with only slight interference.

Abstract: This invention relates to a threaded joint for steel pipes which comprises a pin and a box each having a contact surface including a threaded portion and an unthreaded metal contact portion and which can be prevented from galling during repeated fastening and loosening without application of a compound grease. A solid lubricant coating which comprises a lubricating powder such as molybdenum disulfide and a resin binder is formed on the contact surface of at least one of the pin and the box. The solid lubricant coating has a hardness of 70-140 on the Rockwell M scale and an adhesive strength of at least 500 N/m as determined by the SAICAS (Surface And Interfacial Cutting Analysis System) method, and it exhibits excellent galling resistance even in the environment of high-temperature oil wells. Inclusion of ultraviolet screening fine particles such as titanium oxide fine particles in the solid lubricant coating increases the rust preventing properties of the threaded joint.