Abstract:
Radial seal type threaded joints for steel pipes have still room for improvement in ensuring sealability in terms of the rigidity of the pin nose. Specifically, the outer circumferential surf ace of the nose ( 8) of the pin ( 3) has an outward convex curved shape, and the sealing surface of the box (1) has a tapered shape; and the cross- sectional area of the pin (3) at a seal point, sp that is a portion on the outer circumferential surface of the nose (8) of the pin (3), the portion first coming into contact with the sealing surf ace of the box ( 1) when threaded-joined, is 35% or more of the cross-sectional area of an original pipe portion corresponding to an unprocessed portion. Figure 1
Abstract:
Provided is a screw joint for steel piping that exhibits excellent sealing properties even when subjected to a bending load. Specifically provided is a screw joint for steel piping in which a pin (3) and a box (1) are coupled by means of screw coupling, bringing the outer peripheral surface of the nose portion of the pin (8) and the inner peripheral surface of the nose portion of the box into metal to metal contact, this contact portion forming a seal portion (20). The load flank angle α of the screw portion (the screw coupling portion of a male screw (7) and a female screw (5)) is the load side and the torque shoulder angle &bgr; of a shoulder portion (12, 14) is the load side, and L/d
Abstract:
La presente brinda una unión roscada para una tubería, en la cual se mejoran la capacidad de sellado, la resistencia a la compresión y la resistencia al desgaste por roce. Específicamente, una superficie periférica externa de la protuberancia del pasador (30) forma una curva convexa orientada hacia afuera en la vista transversal axial; la curva convexa es tal que una curva R compuesta (N), en la cual una pluralidad de arcos convexos orientados hacia afuera que tienen diferentes radios de curvatura (Rs) se conectan secuencialmente con una línea de generación de una parte cilíndrica próxima al miembro macho (5), se curva de tal modo que los radios de curvatura (Rs) de los arcos aumentan con la distancia desde el miembro macho (5) y las tangentes en puntos de conexión de los arcos están alineadas con las de los arcos correspondientes conectados; y la superficie periférica interna de un componente caja (1) opuesta a la protuberancia del pasador (30) es una superficie cónica (20) que interfiere con la superficie periférica externa de la protuberancia del pasador (30) cuando se conecta con un componente pasador (3).
Abstract:
Provided is a screw joint for steel piping that exhibits excellent sealing properties even when subjected to a bending load. Specifically provided is a screw joint for steel piping in which a pin (3) and a box (1) are coupled by means of screw coupling, bringing the outer peripheral surface of the nose portion of the pin (8) and the inner peripheral surface of the nose portion of the box into metal to metal contact, this contact portion forming a seal portion (20). The load flank angle α of the screw portion (the screw coupling portion of a male screw (7) and a female screw (5)) is the load side and the torque shoulder angle &bgr; of a shoulder portion (12, 14) is the load side, and L/d
Abstract:
Disclosed is a pipe screw coupling that has increased sealing properties, compression resistance, and galling resistance. Specifically, the pin nose outer peripheral surface (30) forms a convex curve on the outside thereof in a cross section in the axial direction. Said convex curve has a curved shape wherein a compound-R curve (N) comprising a plurality of outwardly convex arcs that are connected in sequence and that have radii of curvature (R) that differ from each other at the generating line of a cylindrical section that is adjacent to a male screw section (5) is such that the radii of curvature (R) of the arcs increase with distance from the male screw section (5) and the line tangent to the connection point of an arc is the same as that of the arc connected to. The inner peripheral surface relative to the pin nose (30) of a box member (1) has a tapered surface (20) that interferes with the pin nose outer peripheral surface (30) when connecting with the pin member (3).
Abstract:
Se provee una junta roscada para caños de acero que tiene una alta capacidad de sellado, incluso bajo una carga de flexión. Para ser específicos, en la junta roscada, cuando un vástago 3 y una caja 1 se enroscan entre sí, la cara periférica exterior de una cara libre 8 del vástago y la cara periférica interior de una cara libre de la caja se encuentran en contacto de metal con metal entre sí, en una porción de contacto, y la porción de contacto sirve como una porción de sellado 20. Una porción roscada (en la cual la porción con roscas externas 7 y la porción con roscas internas 5 se enroscan entre sí) tiene un ángulo lateral de carga negativo a, unas porciones del brazo 12 y 14 tienen un ángulo del brazo de torque negativo b, y la relación L/d0 de un largo L de la cara libre y un diámetro externo del caño d0 es igual o superior a 0,08.