| 摘要 |
An elevator apparatus for manipulating well bore tubing includes a circular body having a top and a central cavity around a body axis. The cavity has a diameter allowing the collar portion of the tubing to pass longitudinally therethrough. A plurality of cavity restricting members above the body, supported on and spaced apart around the top of the body, have proximal and distal portions in respect to the cavity. One or more actuators are operatively associated with the petal plates for moving the proximal portion of each cavity restricting member into the cavity an extent sufficient, in combination with the other cavity restricting members so moved, to prevent passage of the collar portion of the tubing through the cavity, thereby to hold the tubing with the elevator. |
