TUBING HEAD Russian patent published in 2002 - IPC

FIELD: mining industry; applicable as wellhead equipment in operation of oil, gas, gas-condensate wells. SUBSTANCE: tubing head includes body with connecting flanges and upper and lower side branches. Body has step axial and radial channels. Installed in axial channel is pipe holder which is locked by stop screws. Located above pipe holder in body axial channel is ball shutoff member with upper and lower seals and through and blind axial channels. Outer diameter of pipe holder is less than inner diameter of through axial channel in ball shutoff member. Ball shutoff member is controlled by turning shaft. Axis of turning shaft and also axes of through and blind axial channels of ball shutoff member are mutually perpendicular and crossing in one point. Adapter flange is installed on body from atop. Installed in body axial channel is pressure bushing engageable with upper seat. Circular bore is made on level of lower side branches in body axial channel. Circular bore accommodates branch pipe, spring and circular piston. Body has radial holes in which bolts with conical end tips are installed and which may be engageable with upper end face of circular piston. Throttling unit may be located in blind axial channel of ball shutoff member. Similar throttling units may be installed in body upper branches. EFFECT: higher reliability and ecological safety in process of operation of tubing head, simplified its servicing and repairs, and prevented nonsanctioned taking of formation fluid. 3 cl, 3 dwg