| 摘要 |
Apparatus (100) for pulling a projecting tube (14) from a tube sheet (12), along the tube axis (18), comprising a base (200) for engaging the tube sheet and a jacking assembly (300) mounted on the base and actuable by a first fluid pressure variation between extended and retracted positions (302) away from and toward the base respectively. A substantially annular gripper assembly (400) is connected to the jacking assembly for extended and retracted movement therewith and adapted to coaxially receive the tube. The gripper assembly includes a housing (404) having a gripper piston chamber (410) in which a second fluid pressure variation can be introduced into the gripper piston chamber. A gripper piston (420) is situated for movement in the gripper piston chamber in response to the second fluid pressure in the chamber. The gripper piston includes a substantially annular body portion (422) having a bearing surface (436) facing the axis, a gripper (402) supported in contact (434) with the body portion bearing surface, for movement toward the axis to engage and grip the tube in response to the movement of the gripper piston when the second fluid pressure increases in the gripper piston chamber, and first and second fluid pressure ports (226, 418) associated respectively with the jacking assembly and the gripper assembly, whereby the gripper piston can be actuated and the jacking assembly extended to grip and pull the tube. |
