a single ring following the circumference perimeter of each seat 112 114 that may be separate from or integral to the seats 112 114 the first seat 112 which is structurally analogous to the second seat 114 includes a cone shaped member 120 affixed to the inside of the housing 110 such as by a weld orientation of the cone shaped member 120 faces an apex of the cone shaped member toward the flow through the first seat 112 a tubular shaped ring 122 affixed to the smallest inside diameter of the cone shaped member 120 provides a seat surface 124 directed toward the first disc 113 when the disc and lever arm assembly 102 is in the second position any known connection such as a weld may affix the tubular shaped ring 122 to the cone shaped member 120 the seat surface 124 and an inside surface of the tubular shaped ring 122 may include a surface finish having a high resistance to abrasion and erosion such as but not limited to a stellite 1 coating welded thereto similarly a peripheral portion of the disc 113 that contacts the seat surface 124 may include a surface finish having a high resistance to abrasion and erosion such as but not limited to a stellite 1 coating welded thereto and finished by machining or grinding the surface finishes on the seats 112 114 and or discs 113 115 help ensure proper sealing when in contact with each other while the seats 112 114 are shown having the cone shaped member 120 and the tubular shaped ring 122 the actual design or structure of the seats.