Patent ID: 9617821
Date: 2017-04-11
CPC Classifications: E21B

Claim:
1. A swellable packer, comprising: a base pipe; at least one first swellable seal on the base pipe, the first seal comprising a first swellable material; and at least two second swellable seals on the base pipe, the second swellable seals comprising a second swellable material, and the first and second swellable materials being different materials, wherein two of the second swellable seals longitudinally straddle the first swellable seal, and wherein the first swellable material swells faster than the second swellable material in response to contact with an activating agent, wherein each of the second swellable seals contacts the first swellable seal other along a respective frusto-conical interface surface, and wherein the second swellable seals hold back ends of the first swellable seal from swelling while the first swellable seal pushes the second swellable seals outward into contact with a well surface in response to contact between the first swellable seal and the activating agent.