Patent ID: 9022104
Filing Date: 2015-05-05
Classification: E21B

Abstract:
1. A blade assembly of a blowout preventer for shearing a tubular of a wellbore penetrating a subterranean formation, the blowout preventer having a housing with a hole therethrough to receive the tubular, the blade assembly comprising: a ram block movable between a non-engagement position and an engagement position about the tubular; a blade carried by the ram block to cuttingly engage the tubular; and a retractable guide carried by the ram block and slidably movable therealong, the retractable guide having a guide surface to urge the tubular into a desired location in the blowout preventer as the ram block moves to the engagement position; wherein the guide surface is concave with an apex along a central portion thereof and wherein the blade has a puncture point extendable beyond the apex.