SWAB Russian patent published in 2002 - IPC

FIELD: oil and gas producing industry. SUBSTANCE: swab is designed for use as intrawell sealing device included into equipment used for lifting liquid from well at completion and trial operation of well. Swab installed on housing consists of pack of longitudinal load-bearing members (slips), support ring base, replaceable sealing flexible member placed inside pack of longitudinal load-bearing members, and ring lock spring. Longitudinal load-bearing members (slips) are installed in pack over periphery of swab, close to each other in initial position, and they form widening part. Lower part of pack, together with support ring base and ring lock spring, form support-and- lock unit. Support-and-lock part of each longitudinal load-bearing member (slip) is provided with end face steps with recesses from outer side which form support ring cavity in pack. Support ring cavity is semioval in cross section. Support ring base is provided with ring projection in its upper part which is semioval in cross section meeting support ring cavity of pack of longitudinal load bearing members (slips). Projections made at lower end of lock part of longitudinal load-bearing member (slips) on outer side of side surface form ring projection in pack getting into corresponding ring groove made on inner surface of support ring base. Ring-lock spring is fitted in groove formed at assembling on inner surface of lock part of pack of longitudinal load-bearing members. Cavity of pack lock part and corresponding projection of support ring base are semioval in cross section. Longitudinal load-bearing members are relatively rigid, with cross section in widening part in form of ring sector of circumference. Wedge-shaped recesses are made in widening part of pack of longitudinal load-bearing members in place of their joint from inner side to which projections found on outer surface of replaceable flexible sealing member correspond. EFFECT: improved efficiency of swabbing at completion and trail operation of well. 4 cl, 3 dwg