Patent ID: 8439327

Claim:
A shear blowout preventer (BOP), comprising: a body having a horizontal elongated cavity extending along a horizontal axis and a vertical elongated cavity extending perpendicular to and intersecting the horizontal elongated cavity; a shear block provided in the horizontal elongated cavity and configured to slide along the horizontal axis, wherein the shear block has upper and lower surfaces and a frontal face facing the vertical elongated cavity and the frontal face is configured to slide towards the vertical elongated cavity; a shear blade having a rear face attached to the frontal face of the shear block and configured to shear a tool provided in the vertical elongated cavity when the shear block slides towards the tool; an elongated groove extending across one of the faces, the groove having opposite edges defining a face opening at said one of the faces, an inclined wall extending from each of the edges into said one of the faces, the inclined walls diverging from each other from the face opening to a base of the groove, defining a dovetail configuration; and a pin member protruding from the other of the faces, the pin member having a configuration that mates with the elongated groove to retain the shear blade on the shear block.