Patent ID: 8740174

Claim:
A ram-type blowout preventer, comprising: a body; a vertical bore through the body; a horizontal bore through the body intersecting the vertical bore; a pair of ram blocks disposed in the horizontal bore on opposite sides of the body, wherein the ram blocks are configured to move along the horizontal bore to have controlled lateral movement to and from the vertical bore; a seal carrier disposed about the vertical bore between the body and adjacent to the horizontal bore; and a sealing device positioned between the body and the seal carrier; wherein the seal carrier is configured to be displaced along an axis of the vertical bore such that the seal carrier moves unbiased within a predetermined range along the vertical bore, and the sealing device is positioned further away from the axis of the vertical bore than a top seal of the at least one of the pair of ram blocks such that when a pressure from above the pair of ram blocks is applied, a net force is generated that pushes the seal carrier towards the pair of ram blocks.