PACKER Russian patent published in 2003 - IPC

FIELD: oil and gas producing industry. SUBSTANCE: packer has system of slips installed successively from top down in cased well and engageable with control surface and whose initial position is locked by shear pin and self-sealing collar made of flexible material. Packer has spring device located above slips on threaded bushing and ensuring packer coaxial position with respect to casing string. Packer has centralizing device located below self-sealing collar. Centralizing device has spiral guide projection on its side surface. In zone of location of slips and self-sealing collar, packer is provided with protective case installed on shear pin and embracing said slips and collar. Casing string in zone of packer location has section whose cross-section area is smaller than cross-section area of casing string sections located above with formation of circular rest on casing string internal surface which is engageable with protective case in the course of packer setting. Made on casing string section with smaller flow area is circular bore for engagement with slips and for packer locking in casing string. Slips and self-sealing collars are installed with axial motion relative to protective case after cutting of shear pin with subsequent locking of slips in circular bore and location of self-sealing collar on casing string section with smaller flow area. EFFECT: higher reliability of packer setting. 1 dwg