| 摘要 |
FIELD: oil-and-gas production field; devices for oil and gas well operation. ^ SUBSTANCE: device includes flow string, production tubing with circulatory valve, lower and upper stop block of ramming piston, packer, liner and ramming piston inside. Lower stop block of ramming piston rests upon internal flange of circulatory valve case, and consists of upper and lower feet connected with each other by two to twelve connective webbings. Central hole is made in centre of upper foot, and peripheral through holes are located in circular part of foot. External surface of lower foot has flange and central hole is made with cone profile. ^ EFFECT: operational capability and reliability of device is increased. ^ 4 cl, 5 dwg |
