Compression-set plug including an outer soft material which has a removable cover to protect the soft material during running in

摘要

A high expansion packer or bridge plug is described. It features an external portion of a soft material 28 that flows into spiral exterior leak paths 30 formed when the sealing element 20 is subjected to longitudinal compression. Preferably, the sealing element is an elastomer such as cured rubber, while the outer material 28 is a soft uncured or somewhat cured rubber. The outer covering 28 may itself be covered for protection when running in with such protective covering 36 breaking or otherwise getting out of the way during the element compression process. As a result of compression, the soft material occupies the exterior helical or other leak paths for a sufficient length along the scaling element to withstand high differential pressures, without leakage.