| 摘要 |
An overshot tool for retrieving an object in a well includes a housing having a housing bore with upper and lower portions. A cam having a cam bore is carried in the upper portion of the bore. The housing and the cam are rotatable relative to each other from an aligned position, in which the cam bore axis and the housing bore lower portion axis coincide, to a misaligned position, in which the cam bore axis and the housing bore lower portion axis are misaligned with each other. The housing bore and the cam bore are open at a lower end for sliding over an object in the well when the tool is in the aligned position. Rotation of the housing and the cam relative to each other causes the cam bore axis and the lower portion axis to move toward the misaligned position, thereby gripping the object for retrieval. |
