Patent ID: 7207382

Claim:
A system for shearing an oil field tubular product, comprising: a. a blowout preventer body having an opening disposed therethrough for the tubular product; b. a first ram coupled to the blowout preventer body along a first guideway formed in the body having a guide surface for the first ram disposed at an angle to a centerline of the opening, comprising: i. a blade seal comprising: a) a first retainer with a first arcuate surface having a first radius and a centerpoint for the radius; b) a sealing element coupled to the first retainer; ii. a first ram block comprising: a) a V-shaped cutter extension having a first blade extending toward the centerline; and b) the ram block having a blade seal support disposed in a recessed portion of the block away from the centerline relative to the cutter extension and adapted to support the blade seal, the blade seal support having a first arcuate retainer stop, the first arcuate retainer stop having a radius with a centerpoint common to the first arcuate surface centerpoint of the first retainer and adapted to allow engagement with the blade seal; c. a second ram coupled to the blowout preventer body along a second guideway formed in the body having a guide surface for the second ram disposed at an angle to a centerline of the opening, comprising: i) a second ram block comprising a V-shaped cutter extension having a second blade extending toward the centerline and disposed in a different plane that the first blade to allow the second blade to pass the first blade during the shearing and contact a sealing element of the blade seal disposed in the first ram afler the shearing; d. a first actuator coupled to a first ram and adapted to move the first ram toward the centerline; and e. a second actuator coupled to the second ram and adapted to move the second ram toward the centerline, wherein first ram block comprises a second arcuate retainer stop disposed away from the centerline relative to the first arcuate retainer stop, the first and second arcuate retainer stops having a common centerpoint, and wherein the sealing element comprises a sealing element arcuate surface disposed away from the centerline relative to the first retainer and having a common centerpoint with the first arcuate surface of the first retainer, the sealing element arcuate surface sized to engage with the second arcuate retainer stop.