Shear rams for a blowout preventer

A blowout preventer system, comprising:

• a body surrounding a bore configured to enable fluid flow between a wellhead and a drilling riser;
• a first ram disposed adjacent a first end of the body, wherein the first ram is coupled to a first actuator;
• and
• a second ram disposed adjacent to a second end opposite the first end of the body, wherein the second ram is coupled to a second actuator,
• wherein the first ram, the second ram, or both, comprise:
• a body portion having a tapered surface, wherein the body portion comprises a first hardness;
• and
• a ledge comprising a top surface, a bottom surface opposite the top surface, and a tubular contact surface having a length extending from a first end in contact with the bottom surface to a second end in contact with the top surface, wherein the top surface and the bottom surface extend radially away from the tapered surface with respect to a central axis of the bore, wherein the entire length of the tubular contact surface is substantially parallel to a surface of a tubular string extending through the bore when the first ram and the second ram are used during a shearing process, wherein the ledge comprises a second hardness, greater than the first hardness;
• and wherein the width of the ledge extends horizontally with respect to the vertical orientation of the central axis of the bore across the width of the first ram, the second ram, or both.

A method, comprising:

• monitoring a well condition of a wellbore, wherein a tubular string is disposed in the wellbore;
• actuating a blowout preventer having opposed shearing rams when the well condition is indicative of blowout conditions, wherein each of the opposed shearing rams comprises a ledge, extending a distance from a surface of each of the opposed shearing rams, wherein the ledge comprises a top surface, a bottom surface opposite the top surface, and a tubular contact surface having a length extending from a first end in contact with the bottom surface to a second end in contact with the top surface, wherein the top surface and the bottom surface extend the distance radially away from the surface of each of the opposed shearing rams with respect to a central axis of the wellbore;
• and wherein the width of the ledge extends horizontally with respect to the vertical orientation of the central axis of the wellbore across the width of each of the opposed shearing rams;
• directing the opposed shearing rams toward one another into a first position, wherein the entire length of each tubular contact surface of each ledge of the opposed shearing rams is substantially parallel to and contacts an outer surface of the tubular string in the first position;
• and
• directing the opposed shearing rams toward one another into a second position, wherein the opposed shearing rams overlap in a direction of movement of the opposed shearing rams in the second position, such that the tubular string is sheared when the opposed shearing rams are in the second position.