High torque threaded casing joint

摘要

The utility model can be used to connect elements of casing strings, in particular directional casing strings. A threaded connection includes female and male elements, while the outer surface of the male element includes a section with a trapezoidal unequal thread, threaded sections located on different sides of the threaded section, a thrust end, and the inner surface of the female element includes a surface section with a trapezoidal unequal thread, threadless surface sections located on different sides of the threaded section, persistent ledge. In this case, the persistent end face of the male element and the persistent ledge of the female element are in contact, the angle of inclination of the embedded side surface of the thread of the female element is greater than the angle of inclination of the embedded side surface of the thread of the male element, and the tops of the protrusions and the grooves of the threads of the elements are made of cylindrical and conical surfaces. The angle of inclination of the conical surface of the tip of the protrusion of the thread of the male element is greater than the angle of inclination of the conical surface of the vertex of the tip of the thread of the male element. The threadless portion of the inner surface of the enclosing element from the side of the thrust ledge has a protrusion associated with the thrust surface of the ledge, while the protrusion is in contact with the threaded portion of the outer surface of the covered element. The threadless portion of the outer surface of the male member located on the other side of the threaded surface portion than its thrust end has a protrusion in contact with the threadless portion of the inner surface of the female member located on the other side of the threaded surface portion than its thrust shoulder. The male element has a thrust ledge, the thrust surface of which is mated with the tip of the protrusion located on the threadless portion of the outer surface of this element, and the female element has a thrust end, mated with a threaded portion of the inner surface of this element, located on the other side of the threaded surface than his stubborn ledge. In this case, the persistent ledge of the male element and the persistent end of the female element are in contact. In a longitudinal section along the axis of symmetry of the threaded connection at the male element, the form of a threaded portion of the outer surface mating with the surface of the thrust end, the shape of the mating surface of the thrust end, the shape of the threaded portion of the outer surface located on the side of the thrust ledge, including the tip of the protrusion, as well as the shape of the mating surface thrust ledge made in straight lines. In a longitudinal section along the axis of symmetry of the threaded connection at the enclosing element, the shape of a threaded portion of the inner surface mating with the surface of the thrust end, the shape of the mating surface of the thrust end, the shape of the threaded portion of the inner surface located on the side of the thrust ledge, including the apex of the protrusion conjugated with the surface of the thrust ledge , as well as the shape of the mating surface of the thrust ledge made in straight lines. The technical result achieved using this utility model is to increase the reliability of the casing joint under the action of operational loads, including during their rotation in a variable direction. 6 c.p. f-ly, 9 ill.