Exhaust brake valve

A method of manufacturing a butterfly member of an exhaust brake valve assembly, the method comprising:

• providing a valve housing having an interior surface;
• providing a metal material;
• machining the metal material to form a body configured to be positioned within the valve housing;
• drilling a through bore in a central portion of the body, thereby delimiting a first side of the body from a second side of the body that is opposite the first side;
• positioning the body for a single machining operation;
• and
• machining, during the single machining operation, the body to form a first sealing face on the first side of the body and a second sealing face on the second side of the body, thereby producing the butterfly member,
• wherein the first sealing face defines a first plane and the second sealing face defines a second plane spaced from the first plane, and
• wherein the body is formed to define a gap between a periphery of the body and the interior surface of the valve housing as the body pivots within the valve housing between a closed position and an open position, the gap defining a distance of at least 1.5 mm.

A method of manufacturing a butterfly member of an exhaust brake valve assembly, the method comprising:

• providing a metal material;
• machining the metal material to form a body, wherein the body includes:
• a first surface,
• a second surface opposite the first surface,
• a first spline formed on the first surface, the first spline extending between a central portion of the body and a periphery of the body,
• a second spline formed on the second surface, the second spline extending between the central portion of the body and the periphery of the body, and
• a plurality of protrusions formed on the first surface;
• drilling a through bore in the central portion of the body, thereby delimiting a first side of the body from a second side of the body that is opposite the first side;
• positioning the body for a single machining operation;
• and
• machining, during the single machining operation, the body to form a first sealing face around the periphery of the body on the first side of the body and a second sealing face around the periphery of the body on the second side of the body, thereby producing the butterfly member,
• wherein the first sealing face defines a first plane and the second sealing face defines a second plane spaced from the first plane, and
• wherein the step of positioning the body includes clamping the body in a lathe by exerting a force on the second surface at a first location disposed opposite a first of the protrusions that is formed on the first side of the body proximate the periphery of the body, a second location disposed opposite a second of the protrusions that is formed on the second side of the body proximate the periphery, and a third location disposed opposite a third of the protrusions formed on the second side of the body proximate the periphery, and wherein the second and third protrusions are located on opposite sides of the first spline.