| 摘要 |
A packer has a swellable element and has end rings and compressible elements at each end of the swellable element. The packer may be first set using internal bore pressure to compress one of the compressible elements against one of the end rings with a first hydraulic setting mechanism. The packer may then be set a second time using annulus pressure to compress against the other compressible element with a second hydraulic setting mechanism. Either way, the compressible elements are compressed to expand out to the borehole and to limit extrusion of the swellable element outside the compressed elements. |
