초록 ▼

A pipe coupling assembly of threaded and coupled (T and C) type for forming well strings by operably connecting lengths of pipe or tubes in a coaxially aligned relationship. The interior longitudinal bore of the pipes are preferably lined or coated with a corrosion resistant material. A plastic corr

A pipe coupling assembly of threaded and coupled (T and C) type for forming well strings by operably connecting lengths of pipe or tubes in a coaxially aligned relationship. The interior longitudinal bore of the pipes are preferably lined or coated with a corrosion resistant material. A plastic corrosion barrier seal ring is operably positioned in a recess in the longitudinal bore of the coupling member to protect the metal-to-metal seals, torque shoulders and engaged threads of the coupling assembly and pipes from contact with corrosive fluids. The plastic seal ring prior to thread make up is substantially rectangular in cross-section with a radial dimension between the outside and inside diameter or width equal to a greater than 1.5 times the axial or longitudinal height. With this dimension ratio the plastic seal ring is secured against displacement from the desired sealing position during controlled thread make up in the hostile environment at a well site which deforms only the inner radial portion of the height dimension.

대표청구항 ▼

A coupling member for joining lengths of first and second tubular conduits, each conduit having an annular nose operably positioned within the coupling member to form a well conduit, including: a tubular coupling member defining a longitudinal axis and having a first annular end surface and a second

A coupling member for joining lengths of first and second tubular conduits, each conduit having an annular nose operably positioned within the coupling member to form a well conduit, including: a tubular coupling member defining a longitudinal axis and having a first annular end surface and a second annular end surface and having a longitudinally extending bore formed internally through said coupling member between said first annular end surface and said second annular end surface, said bore forming an inner surface; said inner surface forming a first annular shoulder and a second annular shoulder within said bore, said first and said second annular shoulders being spaced apart a predetermined distance and facing in opposite longitudinal directions; said inner surface forming an annular recess disposed between said oppositely facing annular shoulders, said recess having an outer cylindrical surface and a pair of facing annular surfaces disposed so the outer surface faces toward the center of the bore, said outer surface having an axial height between said facing annular surfaces; a first helical internal thread means formed in said bore by said inner surface adjacent said first annular shoulder for threadedly engaging a corresponding helical external thread means formed on a first tubular conduit for releasably securing the first tubular conduit in coaxial longitudinal axis alignment with said tubular coupling member; a second helical internal thread means formed in said bore by said inner surface adjacent said second annular shoulder for threadedly engaging a corresponding helical external thread means formed on a second tubular conduit for releasably securing the second tubular conduit in coaxial longitudinal axis alignment with said tubular coupling member; said first annular shoulder engaging the first tubular member to limit rotational make up of said first helical internal thread means with the corresponding helical threads on the first tubular conduit for positioning the first tubular member in a predetermined height relationship to said recess; said second annular shoulder engaging the second tubular member to limit rotational make up of said second helical internal threads with the corresponding helical threads on the second tubular conduit for positioning the second tubular member in a predetermined height relationship to said recess; and a resilient seal ring means for forming a corrosion barrier by sealing between the annular nose of the first tubular member and the annular nose of the second tubular member when each tubular member is positioned in the predetermined height relationship to said recess, said resilient seal ring means having a cylindrical inner surface and a cylindrical outer surface that are radially spaced apart to form a width dimension and defining a longitudinal axis, said seal ring means having a first flat annular surface and a second flat annular surface that are longitudinally spaced apart to form a seal ring height dimension that is substantially the same as the height dimension of said outer surface of said recess, said outer cylindrical surface of said seal ring sized for operably positioning adjacent said outer surface of said recess so the longitudinal axis of the seal ring is substantially coaxial with the longitudinal axis of said tubular coupling member, said seal ring means initially being substantially rectangular in cross section having a height substantially the same as the outer surface of said recess and a width that is at least 1.5 times the height prior to sealing engagement with the annular noses of the first and second tubular member; said seal ring means sized to be operably compressively deformed in the height dimension adjacent the inner cylindrical surface by the annular noses of the tubular conduits to form the corrosion barrier seal when the tubular members are in the predetermined height relationship to said recess and with the height dimension of said seal ring adjacent the outer cylindrical surface remaining substantially undeformed in said recess to provide a generally T-shaped configuration to the deformed seal ring means.