Patent ID: 8381754

Claim:
A method of configuring a butterfly valve within a bore, comprising: obtaining a butterfly valve including a butterfly and at least one ring attached to the butterfly; extending the at least one ring completely around a perimeter of the butterfly, wherein the butterfly valve includes a clearance for the at least one ring to expand and contract, wherein the at least one ring is adapted to develop an expansion force in the radial direction when the at least one ring is in a contracted state with respect to the radial direction; contracting the at least one ring to develop the expansion force in the radial direction; securing the at least one ring to the butterfly in the contracted state so that radial expansion due to the developed expansion force of the at least one ring is effectively restrained; placing the butterfly valve within the bore having an inner diameter so that the butterfly valve is in a closed position; unsecuring the at least one ring from the butterfly and permitting the at least one ring to expand to the inner diameter of the bore; and resecuring the at least one ring to the butterfly so that further outward radial expansion of the at least one ring is effectively restrained.