| 摘要 |
The pumping or swabbing device and apparatus of the invention utilizes an elongate barrel slidable upwardly and downwardly on an axial rod which carries a valve element for closing on a valve seat provided interiorly of the barrel to close passage through the barrel of down-hole pressure fluid and cause such fluid to raise barrel and rod of the device through a gas and oil well casing to the wellhead, where liquid above the device is pushed to discharge at the wellhead. Spring actuated detent latching elements coact with a pair of longitudinally spaced lower and upper latching recesses to hold the barrel and rod together against relative movement in lower valve-closed and upper valve-opened positions. A sealing packer encircles the barrel and a by-pass passage thereinto leading from and back into the barrel flow passage provides sealing pressure within such packer as the device rises in the well casing. A manually or pressure operated latch provides for holding the device in the wellhead as desired. |
