Patent ID: 8807516

Claim:
A ram type blowout preventer, comprising: a housing forming a central bore extending generally vertically through the housing, and horizontal ram bores extending radially outwardly in opposite directions through the housing and intersecting the central bore; a pair of rams, each ram having a front end portion, a rear end portion, a top portion and a bottom portion and being adapted to be positioned in one of the horizontal ram bores for sliding movement therein between an extended position, with the front end portion extending across the central bore and the rear end portion within the horizontal ram bore, and a retracted position within the horizontal ram bore, each ram being configured with a front face to seal against the front face of the opposing ram and to accommodate a tubular member, if present in the central bore; a primary rope packing seal formed on each ram from a first length of rope packing of a rope packing material in a braided, twisted, woven or knitted form, the primary rope packing seal extending horizontally across the front face, rearwardly, and then either or both of upwardly over the top portion and downwardly over the bottom portion at a position rearwardly of the front end portion, the primary rope packing seal being held as a closed loop in, so as to protrude radially outwardly from, a continuous first groove formed in the ram, the continuous first groove being adapted to accommodate joined abutting ends or overlapping ends of the first length of rope packing; and an actuator connected to the rear end portion of each ram for extending and retracting the ram between the extended and retracted positions, such that in the extended position the primary rope packing seals on opposing rams seal against each other on opposing front faces, against the tubular member if present, and against the ram bores so that the primary rope packing seals themselves seal the central bore.