초록 ▼

Metal-to-metal seals for pin and box member tubular joints are disclosed where mating annular surfaces are machined at slightly different angles such that the bearing load from initial contact is entirely on the leading edge of the pin annular surface and the trailing edge of the box annular surface

Metal-to-metal seals for pin and box member tubular joints are disclosed where mating annular surfaces are machined at slightly different angles such that the bearing load from initial contact is entirely on the leading edge of the pin annular surface and the trailing edge of the box annular surface. The mismatch of the sealing surfaces is selected for any particular seal geometry such that at final make-up, the bearing load has a relatively even distribution across the entire sealing surface in contact, thus broadly distributing make-up bearing stresses and minimizing any resulting tendency for galling that may occur, in particular for joints having relatively thick walls for both pin and box members.

대표청구항 ▼

A joint adapted for multiple connections and disconnections of oil and gas well pipe sections having an internal bore therein and for sealing against high pressures of such sections comprising, tubular male and female members of high yield strength steel material, said members having companion threa

A joint adapted for multiple connections and disconnections of oil and gas well pipe sections having an internal bore therein and for sealing against high pressures of such sections comprising, tubular male and female members of high yield strength steel material, said members having companion threads adapted to be screwed together, metal-to-metal seal means on said members located adjacent said threads, said seal means including, first frusto-conical seal surface means on an end of one of said members, second frusto-conical seal surface means adjacent a base of the threads of the other of said members, where the angle of inclination of the generatrix of said first seal surface means with respect to the longitudinal axis of the joint initially is less than the angle of inclination of said second seal surface means with respect to such axis, thereby creating an initial angle mismatch between said first and second seal surface means, so that as said threads are screwed together, a zone of substantially line contact initially is effected between said first frusto-conical seal surface means and said second frusto-conical seal surface means which develops into a substantially full area contact seal of an axial length therebetween when said threads are fully made up, said end of said members on which said first frusto-conical seal surface means is located is characterized by a first wall thickness, said second seal surface means formed at a location of said other of said members is characterized by a second wall thickness, and said second wall thickness is greater than said first wall thickness, and wherein said angle of inclination of said first seal surface means, said initial angle mismatch between said first and second seal surface means, said first wall thickness relative to said second wall thickness, and said axial length of said full area contact between said first and second seal surface means, are so constructed and arranged that the bearing load distribution across said full area contact seal is substantially uniform as characterized by maximum pressures of approximately equal magnitude at each end of said seal and by pressures less than said maximum pressures between said ends of said seal and as a result, said joint has enhanced anti-galling sealing characteristics of said first and second seal surfaces such that said joint may be used for multiple connections and disconnections.