Blind shear ram

A shear ram assembly for use in a blow out preventer (BOP) stack with a shear ram housing and a bore, the bore of the BOP configured for alignment with a wellbore when the BOP is attached to a wellhead, the shear ram assembly comprising:

• a ram block disposed within the shear ram housing and having a forward face facing the bore, the ram block movable between an open position, in which the ram block is retracted away from the bore, and a closed position, in which the ram block is extended toward the bore;
• a blade having a forward surface, a rear surface, a lower shearing edge, and an upper edge, the blade attached to the forward face of the ram block by fasteners;
• and
• an upper lip extending from an upper portion of the ram block toward the bore, the upper lip contacting the blade to reduce rotation of the blade relative to the housing as the ram block moves from the open to the closed position, thereby reducing stresses in the fasteners.

A shear ram assembly for use in a blow out preventer (BOP) stack with a shear ram housing and a bore, the bore of the BOP configured for alignment with a wellbore when the BOP is attached to a wellhead, the shear ram assembly comprising:

• a ram block disposed within the shear ram housing and having a forward face facing the bore, the ram block movable between an open position, in which the ram block is retracted away from the bore, and a closed position, in which the ram block is extended toward the bore;
• a blade having a forward surface, a rear surface, a lower shearing edge, and an upper edge, the blade attached to the forward face of the ram block by fasteners;
• a lower lip extending from a lower portion of the ram block toward the bore, the lip separated from the blade by a gap;
• and
• a seal disposed in the gap between the lower lip and the blade for sealing the interface between the ram block and blade.