| CPC E21B 23/06 (2013.01) | 10 Claims |

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9. A method for maintaining energy in a seal during temperature down cycling, comprising:
automatically compensating for temperature related reduction in the seal energy by expanding a set energy compensating device in contact with the seal by increasing dimensions of a negative thermal expansion material associated with the device and pressurizing a noncompressible fluid with the material thereby moving a piston in a chamber, the chamber filled with the fluid and the material.
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