WELLHEAD EQUIPMENT Russian patent published in 2001 - IPC

FIELD: oil field equipment; applicable as well head equipment of oil wells equipped with sucker-rod pumps. SUBSTANCE: wellhead equipment has body with channel for communication with cavity of tubing, channel for communication with annular space and channel for communication of tubing with annular space. Body has cone sleeve for suspension of pipes, disk cutoff valve and casing head stuffing box for sealing of polished rod of sucker-rod pump. Shutoff members are installed in said communication channels. Connected coaxially with shutoff member and tightly to body of wellhead equipment is chamber of sluice box type. This chamber has movable rod for catching shutoff member and for its motion into chamber space. Chamber has slide gate for disconnection of chamber space from working cavity of wellhead equipment. Chamber internal space is communicated by means of channel with working cavity of wellhead equipment. Channel is closed with needle valve. EFFECT: provided replacement of shutoff members under pressure of working medium. 6 dwg