UNIVERSAL HEAD OF PIPE STRING Russian patent published in 1999 - IPC

FIELD: oil and gas production industry. SUBSTANCE: universal well head is used for connection of casing pipes at head of oil-gas well. It has following components: external pipe string head and internal pipe string head, sealing components in annular clearance between pipe string heads, seating cones, slots for circulation of solution, and pipe unions. Universal head is also provided with components which prevent sliding of internal pipe string head relative to external pipe string head at unscrewing of allowance pipe union. Internal pipe string head has guiding annular shoulder located on its external surface below seating cone. Made in cylindrical surface of guiding annular shoulder are lateral low-module teeth. External pipe string head has insert with mating teeth. Insert is installed in slot of wall with possible reciprocal radial and horizontal movement. Insert is connected with plug axle. Plug has threaded shank which ends in tail-piece for wrench. Plug is installed in threaded bush which in its turn is hermetically secured in wall of external pipe string head. Application of aforesaid universal pipe string head widens functional potentialities, prevents uncontrolled turning with subsequent unscrewing of pipes in production pipe string at unscrewing of allowance pipe union which altogether results in enhancing operational reliability. EFFECT: higher efficiency. 2 dwg