DEVICE AND METHODS OF CONTROL OVER TUBULAR ELEMENTS Russian patent published in 2015 - IPC E21B19/06 

FIELD: transport.

SUBSTANCE: set of invention relates to devices and methods for control over pipes in round-trip operation. Proposed device comprises pipe lowering tool, pipe lifting tool and pre-straining mechanism. Said pipe lowering tool comprises the element with several elongated cutouts extending in direction parallel with pipe lengthwise axis, element with recesses coupled with said elements with cutouts, each cutout extending between deep end and shallow end, and several sliding elements engaged with several cutouts and recesses that displace in the pipe direction and interact with the latter so that said tool grips the pipe. Lifting tool allows engagement of said pipe with pipe lowering tool. Aforesaid pre-straining mechanism allows a reversible application of axial force to pipe end gripped by pipe lowering tool for gripping of said pipe. Note here that pipe lowering tool can grip every pipe with appropriate load bearing capacity to prevent pipe fall irrespective of jobs performed by pipe lifting tool.

EFFECT: higher safety.

27 cl, 8 dwg