The disclosed threaded connection for steel pipes includes a pin including a tapered male thread part and a shoulder part, and a box including a tapered female thread part and a shoulder part. In a made up state in which the shoulder parts are in contact with each other, clearances are provided between crests of the male thread part and roots of the female thread part. At a longitudinal section that includes a pipe axis of the threaded connection, the crests of the male thread part are formed in a convex curve that is tangent to both first corner portions which are formed in an arc that connect the crests and load flanks, and second corner portions which are formed in an arc that connect the crests and stabbing flanks. A solid lubricant coating is provided on the surface of the male thread part.

A threaded connection includes a pin and a box. The pin includes, in the order from a free end side of the pin toward a tubular body side thereof, an inner sealing surface, an inner male threaded portion, a shoulder portion, an outer male threaded portion, and an outer sealing surface. The box includes, in the order from a tubular body side of the box toward a free end side thereof, an inner sealing surface, an inner female threaded portion, a shoulder portion, an outer female threaded portion, and an outer sealing surface. Between the inner sealing surface and the inner female threaded portion of the box, an inner groove along a circumferential direction is provided, and some threads of the inner male threaded portion of the pin are contained in the inner groove.

A threaded connection that provides high sealing performance is provided. A threaded connection (10) includes a pin (1) and a box (2). An inner male thread (13) of the pin (1) includes a parallel portion (131). The parallel portion (131) is located at an end portion of the inner male thread (13) adjacent to the pin inner sealing surface (11), and has thread roots parallel to the pipe axis. An inner female thread (23) of the box (2) includes a tapered portion (231). The thread height in the tapered portion (231) is larger than that in the parallel portion (131). Da<Db is satisfied, where Da is the difference in diameter between adjacent thread crests (231a) in the tapered portion (231) in a longitudinal cross section of the pin (1) and box (2) as found when the connection is not made up, and Db is the difference between the diameter of the thread root (131a) in the parallel portion (13) and the maximum diameter of the pin inner sealing surface (11).

An assembly for producing a threaded connection includes first and second tubular components with an axis of revolution and each provided at one end with at least first, second, and third continuous threaded zones provided in succession on the same helix on the outer or inner peripheral surface of the component depending on whether the threaded end is male or female. The components are capable of cooperating together upon makeup. At least one of the first, second, or third threaded zones has a variable width thread profile and is self-locking. The ends respectively finish in a free terminal surface. Each of the ends is free of a specific abutment surface. At least one sealing surface is provided between each of the adjacent threaded zones in order to cooperate in a sealed interference fit with a sealing surface provided on the corresponding end when the connection is made up.

A tubular connection includes a tubular joint including a pin with a first pin thread having a first pitch and a second pin thread having a second pitch, and also includes a connector that includes a box with a first box thread having the first pitch and a second box thread having the second pitch. The connection also includes an elastomeric seal ring comprised of a material that swells in the presence of hydrocarbons. Upon make-up of the connection, the first pin thread engages with the first box thread, the second pin thread engages with the second box thread, and the elastomeric seal ring is disposed around the tubular joint between the first pin thread and the second pin thread and forms a metal-to-elastomer seal between the tubular joint and the connector.

A cap is described for connection to a medical connector, the cap includes a housing having a top wall and sidewall forming a first cavity, and a removable or integrally formed protrusion. The protrusion includes an inner thread on an inner surface, the inner thread being sufficient to interlock with a mating feature of a female needleless connector. The inner surface of the protrusion defines a second cavity. The protrusion includes an outer thread on an outer surface, the outer thread being sufficient to interlock with a mating feature of a male needleless connector. The second cavity configured to define a chamber to contain an absorbent material and disinfectant or antimicrobial agent. The cap may also include a peel seal and/or septum to prevent the disinfectant or the antimicrobial agent from exiting the second cavity. An exterior sidewall surface of the housing may include a plurality of grip members.

A threaded joint for oil well steel pipe is provided. The threaded joint includes a pin provided with a male thread, and a box provided with a female thread threadedly engaged with the male thread, and at an outer periphery side sealing portion, a cross-sectional area S1 of the pin at a seal point, and a cross-sectional area S0 of a pipe body portion, which is an unprocessed pin portion, satisfy an expression (S1/S0)10015(%), at an inner periphery side sealing portion, a cross-sectional area S2 of the box at a seal point, and a cross-sectional area S0 of a pipe body portion, which is an unprocessed box portion satisfy an expression (S2/S0)10020(%), and a surface area S3 of a contact portion of an intermediate shoulder between thread rows and the cross-sectional area S0 satisfy the expression (S3/S0)10010(%).

A threaded connection for drilling tubulars includes a tubular box section having a sidewall. The box section has a tapered box portion of an inner surface of the sidewall between a first end and a second end. The tapered box portion has internal threads, a first torque shoulder on a first side of the tapered box portion, and a second shoulder on a second side of the tapered box portion. A threaded collar having internal collar threads is positioned between the second end and the second shoulder. A threaded insert having a tubular body with an inner surface and an outer surface having external insert threads is configured for threadably connecting to the internal collar threads. A direction of the internal threads of the tapered box portion is opposite to a direction of the internal collar threads and the external insert threads.

The application relates to a threaded cylindrical member, which may be used for a segmented drilling tube. The member has opposing first and second ends and a central axis between the ends. The first end is threaded with a pin thread including a pressure flank, a crest and a root. The second end is threaded with a box thread including a pressure flank, a root, wherein the pin and box threads are configured whereby when threaded together a portion of the root of the pin thread is out of contact with the crest of the box thread to leave gap therebetween. The secondary geometries of the pin and box threads are configured to generate an interference fit between the pin and box threads. The roots and crests of the pin and box threads define parallel tapering conical frustrums that differ from each other in their taper angles.

A cap is described for connection to a medical connector, the cap includes a housing having a top wall and sidewall forming a first cavity, and a removable or integrally formed protrusion. The protrusion includes an inner thread on an inner surface, the inner thread being sufficient to interlock with a mating feature of a female needleless connector. The inner surface of the protrusion defines a second cavity. The protrusion includes an outer thread on an outer surface, the outer thread being sufficient to interlock with a mating feature of a male needleless connector. The second cavity configured to define a chamber to contain an absorbent material and disinfectant or antimicrobial agent. The cap may also include a peel seal and/or septum to prevent the disinfectant or the antimicrobial agent from exiting the second cavity. An exterior sidewall surface of the housing may include a plurality of grip members.