Valve seat insert for high power density and high speed diesel engines

A valve seat insert for an intake valve in an internal combustion engine comprising:

• an annular insert body defining a valve seat center axis extending between a first axial end surface structured for facing the cylinder in the internal combustion engine, and a second axial end surface;
• the annular insert body further having an inner peripheral surface defining a throat structured to fluidly connect the cylinder to an intake conduit in an engine head, an outer peripheral surface, and a valve seating surface for contacting an intake valve extending between the first axial end surface and the inner peripheral surface;
• the valve seating surface including, in profile, an outer curved segment forming a first wear crown for contacting the intake valve at an early wear state, an inner curved segment forming a second wear crown for contacting the intake valve at a later wear state, and a linear segment extending between the outer curved segment and the inner curved segment;
• and
• the inner peripheral surface including, in profile, a vertical segment extending downwardly from the second axial end surface to the inner curved segment.

A valve seat insert for an exhaust valve in an internal combustion engine comprising:

• an annular insert body defining a valve seat center axis extending between a first axial end surface structured for facing the cylinder in the internal combustion engine, and a second axial end surface;
• the annular insert body further having an inner peripheral surface configured to fluidly connect the cylinder to an exhaust conduit in an engine head, an outer peripheral surface, and a valve seating surface for contacting an exhaust valve extending between the first axial end surface and the inner peripheral surface;
• the valve seating surface including, in profile, an outer curved segment forming a first wear crown for contacting the exhaust valve at an early wear state, an inner curved segment forming a second wear crown for contacting the exhaust valve at a later wear state, and a linear segment extending between the outer curved segment and the inner curved segment;
• the inner peripheral surface including, in profile, a vertical segment extending downwardly from the second axial end surface, and a sloping segment extending between the vertical segment and the valve seating surface;
• and
• the sloping segment extending radially outward from the vertical segment toward the valve seating surface at an acute angle, of about 6° or greater, relative to the valve seat center axis.