A connector for connecting a fluid pipeline includes an inner socket, which is a columnar body having a channel, and both ends defined as a first end and a second end. The inner socket has a guide portion, an attaching portion, an anti-leak portion and a connecting portion sequentially arranged on the outer side from the first end to the second end; the first end is socketed into an end of a tube by the guide portion; the attaching portion is a spiral concave groove on an outer side of the inner socket for attaching an inner side of the tube; the anti-leak portion is between an end of the tube and the connecting portion for sealing an opening of the tube; and the connecting portion is between the anti-leak portion and the second end and exposed from the tube for connecting another connecting portion of another connector.

A connector for connecting a fluid pipeline includes an inner socket, which is a columnar body having a channel, and both ends defined as a first end and a second end. The inner socket has a guide portion, an attaching portion, an anti-leak portion and a connecting portion sequentially arranged on the outer side from the first end to the second end; the first end is socketed into an end of a tube by the guide portion; the attaching portion is a spiral concave groove on an outer side of the inner socket for attaching an inner side of the tube; the anti-leak portion is between an end of the tube and the connecting portion for sealing an opening of the tube; and the connecting portion is between the anti-leak portion and the second end and exposed from the tube for connecting another connecting portion of another connector.

A threaded pipe connection includes a first tubular member having a pin end defining external threads, a second tubular member having a box end defining internal threads threadably engageable with the external threads of the pin end, and a thread profile that defines at least a portion of one of the internal or external threads and includes a crest, a root, and a transition surface extending between the crest and the root. The transition surface includes a first arcuate surface extending from a top of the crest at a first radius, a second arcuate surface extending from the first arcuate surface at a second radius, and a third arcuate surface extending from the second arcuate surface at a third radius. The first radius and the third radius are each smaller than the second radius.

A threaded pipe connection includes a first tubular member having a pin end defining external threads, a second tubular member having a box end defining internal threads threadably engageable with the external threads of the pin end, and a thread profile that defines at least a portion of one of the internal or external threads and includes a crest, a root, and a transition surface extending between the crest and the root. The transition surface includes a first arcuate surface extending from a top of the crest at a first radius, a second arcuate surface extending from the first arcuate surface at a second radius, and a third arcuate surface extending from the second arcuate surface at a third radius. The first radius and the third radius are each smaller than the second radius.

A tubular member for threadably engaging another tubular member to form a tubular string includes a first end including a helical female thread formed in an outer surface of the tubular member, wherein the female thread includes a slot extending radially inwards from the outer surface, and a root extending radially inwards from the slot, wherein the root has a maximum width that is greater than a maximum width of the slot, a second end opposite the first end and including a helical male thread formed on an inner surface of the tubular member, wherein the male thread includes a shank extending radially outwards from the inner surface, and a notch extending radially outwards from the shank, wherein the notch has a maximum width that is greater than a maximum width of the shank.

An optimized thread profile (140) for joining composite materials is presented. This thread profile (140) maintains a certain material strength when used as part of a composite threaded joint (101). The thread profile (140) comprises a repeating pattern of four components: a crest region (150), a first flank (162), a root region (170) and a second flank (164). The thread profile (140) is symmetrical, that is, the dimensions of the four components do not change throughout the length of the thread profile. The crest (152) has a flat profile and the root (172) has a rounded profile. When a shaft (120) is affixed to a joining shaft (110) using this optimized thread profile (140), the flat profiles of the crest (152) of the shaft (120) and corresponding rounded profiles of the root (172) of the joining shaft (110) create a gap to accommodate a substance such as an adhesive or a lubricant. Similarly, the flat profiles of the crest (152) of the joining shaft (110) and corresponding rounded profiles of the root (172) of the shaft (120) create a gap to accommodate a substance.

A connection includes a first tubular member having a first screw threadform defined by a first plurality of crests, roots, and flanks, where each flank separates each crest from each root. The connection also includes a second tubular member having a second screw threadform defined by a second plurality of crests, roots, and flanks, where each flank separates each crest from each root. The crests and roots are substantially axial to the tubular members and the flanks are substantially radial to the tubular members. The first tubular member and the second tubular member are configured to connect when the first threadform engages with the second threadform. Thread compound relief spaces are formed between the first plurality of crests and the second plurality of roots and between the second plurality of crests and the first plurality of roots when the first and second tubular members connect.

A connection includes a first tubular member having a first screw threadform defined by a first plurality of crests, roots, and flanks, where each flank separates each crest from each root. The connection also includes a second tubular member having a second screw threadform defined by a second plurality of crests, roots, and flanks, where each flank separates each crest from each root. The crests and roots are substantially axial to the tubular members and the flanks are substantially radial to the tubular members. The first tubular member and the second tubular member are configured to connect when the first threadform engages with the second threadform. Thread compound relief spaces are formed between the first plurality of crests and the second plurality of roots and between the second plurality of crests and the first plurality of roots when the first and second tubular members connect.

A connection includes a first tubular member having a first screw threadform defined by a first plurality of crests, roots, and flanks, where each flank separates each crest from each root. The connection also includes a second tubular member having a second screw threadform defined by a second plurality of crests, roots, and flanks, where each flank separates each crest from each root. The crests and roots are substantially axial to the tubular members and the flanks are substantially radial to the tubular members. The first tubular member and the second tubular member are configured to connect when the first threadform engages with the second threadform. Thread compound relief spaces are formed between the first plurality of crests and the second plurality of roots when the first and second tubular members connect.

A connection includes a first tubular member having a first screw threadform defined by a first plurality of crests, roots, and flanks, where each flank separates each crest from each root. The connection also includes a second tubular member having a second screw threadform defined by a second plurality of crests, roots, and flanks, where each flank separates each crest from each root. The crests and roots are substantially axial to the tubular members and the flanks are substantially radial to the tubular members. The first tubular member and the second tubular member are configured to connect when the first threadform engages with the second threadform. Thread compound relief spaces are formed between the first plurality of crests and the second plurality of roots when the first and second tubular members connect.