BLOWOUT PREVENTION VALVE OF CASING-HEAD STUFFING BOX Russian patent published in 2001 - IPC

FIELD: oil producing industry. SUBSTANCE: blowout prevention valve of casing-head stuffing box includes seal and torsion spring located on axle. Lock is installed on axle and made of two rods connected in lower part of transverse rod. Two rods have transverse parallel holes on their ends. Secured to lock on axle is roller. Opened seal is locked by transverse rod of lock. Roller comes in contact with stuffing box end. Lock axle is installed under opened seal. Roller is located between seal and stuffing box rod above axle. Axles of seal and lock are secured in plates. Blowout prevention valve is located in cavity of body of casing-head stuffing box. Roller secured to lock is made of polymer. After coming of stuffing box out of body, lock turns on axle and frees seal which closes open hole running to stuffing box head. Linkage from seal to lock reduces force of contact of roller and stuffing box rod to increase serviceability of casing-head stuffing box with blowout prevention valve and stuffing box rod. EFFECT: prevented pollution of environment with oil and oil losses in cases of emergency coming of stuffing box rod of casing-head stuffing box. 5 cl, 2 dwg