Swivelsub
OwnerSvein Gleditschinventor
Life of this patent
Estimating the term…
Abstract
A swivelsub comprising a sleeve member which is sealable and lockable by means of the annular preventer of a blowout preventer, with at least one end portion of the sleeve being lockable to the drill string, and with means providing sealing and enable relative rotational movement between said sleeve member and the drill string. The swivelsub forms a sealable and pressure controlling passage for a dril string in a drilling well and is particularly useful for cutting operation of casings in an abandoned well.
Claims5
A swivelsub, for use with an annular preventer of a blowout preventer, said annular preventer having expandable rubber elements to seal off the drill string and to provide a sealable and pressure controlling passage for a drill string, comprising:
- a sleeve member, positioned around said drill string and surrounded by said annular preventer so as to be lockable by said annular preventer and sealable by said expandable rubber elements of said annular preventer;
- retaining means, positioned at one end of the sleeve member, for locking around said drill string for rotation therewith;
- and
- means, positioned at at least one end of the sleeve member, for enabling relative rotation between the sleeve member and the drill string.
Dependencies are inferred from the claim text.