US 4,762,344 AGranted

Well casing connection

AssigneeLee E. Perkins

InventorsLee E. Perkins, James J. Petrella

Life of this patent

Estimating the term…

Loading patent…

Abstract

A well pipe connection wherein the ends of the pipes have complementary sealing surfaces and are joined together by means of an internally threaded tubular connector that engages with corresponding threads on each of the pipe ends. One of the pipe ends has threads of a pitch that is greater than the pitch of the threads on the other pipe end, and the connector threads have corresponding thread pitches. The disclosed arrangement permits the connection to be assembled to the point short of relative sliding movement between the complementary sealing surfaces on the pipe ends and final tightening is accomplished by restraining the respective pipes from relative rotation while rotating the connector to draw the two pipe ends together into compressive sealing engagement without relative sliding in order to prevent galling of the sealing surfaces.

Claims5

Dependent claims

A threaded connection for oil and gas well pipe sections, said connection comprising:

a first pipe section having an external thread formed thereon and having an end terminating in a first sealing surface, said thread having a first pitch;
a second pipe section having an external thread formed thereon and having an end terminating in a second sealing surface for cooperative engagement with said first sealing surface and adapted for sealing engagement therewith, said second pipe section external thread having a second pitch different from the first pitch, said threads on each of said first and second pipe sections being of the same hand when said pipe ends are opposite each other;
an internally threaded tubular connector adapted to engage with the respective threaded ends of said pipe sections, said connector having first threads adjacent one end thereof engagable with and having the same pitch as the threads on said first pipe section and having second threads adjacent the other end thereof engageable with and having the same pitch as the threads on said second pipe section, each of said first and second threads of said connector having the same;
and said first and second pipe sections being threadedly engaged with the corresponding threads of said connector so that final tightening of the section can be accomplished by rotating the connector relative to the pipe sections and without relative rotation between the pipe sections, to draw the pipe ends together axially, without relative sliding between the respective sealing surfaces until the sealing surfaces are engaged under compressive stress, the pitch of said first thread being at least three times the pitch of said second thread.

1 more element

A threaded connection for oil and gas well pipe sections, said connection comprising;

a first pipe section having an external thread formed thereon and having an end terminating in a first sealing surface, said thread having a first pitch;
a second pipe section having an external thread formed thereon and having an end terminating in a second sealing surface for cooperative engagement with said first sealing surface and adapted for sealing engagement therewith, said second pipe section external thread having a second pitch different from the first pitch, said threads on each of said first and second pipe sections being of the same hand when said pipe ends are opposite each other;
an internally threaded tubular connector adapted to engage with the respective threaded ends of said pipe sections, said connector having first threads adjacent one and thereof engageable with and having the same pitch as the threads on said first pipe section and having second threads adjacent the other end thereof engageable with and having the same pitch as the threads on said second pipe section, each of said first and second threads of said connector having the same hand;
and said first and second pipe sections being threadly engaged with the corresponding threads of said connector so that final tightening of the section can be accomplished by rotating the connector relative to the pipe sections and without relative rotation between the pipe sections, to draw the pipe ends together axially, without relative sliding between the respective sealing surfaces until the sealing surfaces are engaged under compressive stress, each of said pipe ends having a first sealing surface that is inclined relative to the axis of the connector and a second sealing surface that extends in a direction generally along the axis of the connection, the angles of inclination of said first sealing surfaces on said pipe ends being different from each other to define a divergent angle therebetween having its vertex innermost relative to the pipe axis, the difference between the angles of inclination of said inclined sealing surfaces being from 1.degree. to 5.degree..

1 more element

Dependencies are inferred from the claim text.