| 摘要 |
A compensating system for an inflatable element is disclosed which can be responsive to a temperature increase or decrease and still regulate the inflate pressure of the inflatable element, despite fluctuations in pressures above or below the element. A compensating piston with an atmospheric chamber is used. The compensating piston is coupled to a balancing piston. The balancing piston is ported to receive pressure from above the element on one side, and below the element on the other side. When the apparatus is run in the hole, wellbore pressure causes the compensating piston to be in the collapsed position. Upon inflation, the compensating piston strokes. A positioning mechanism positions the compensating piston in the center to allow it to handle both temperature increases and decreases. Upon complete inflation of the element, the positioning mechanism releases the balancing piston to let it float and porting is opened from above and below the inflated element to the balancing piston. The balancing piston applies an opposite load on the compensating piston to counteract either a change in inject pressure from above or formation pressure from below.
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