Low Pressure Pilot Operated Relief Valve

Abstract

Embodiments of the invention provide a relief valve body arranged between an inlet and an outlet. The relief valve body includes an expanding nozzle extending along an axis, a first ramp extending in an arcuate path from an apex to a first terminal point, and a second ramp extending in an arcuate path from the apex to a second terminal point. The first ramp and the second ramp define an expanding flow area for a fluid flow between the inlet and the outlet.

We claim: 
     
         1 . A relief valve body arranged between an inlet and an outlet, the relief valve body comprising:
 an expanding nozzle extending along an axis;   a first ramp extending in an arcuate path from an apex to a first terminal point; and   a second ramp extending in an arcuate path from the apex to a second terminal point, the first ramp and the second ramp define an expanding flow area for a fluid flow between the inlet and the outlet.   
     
     
         2 . The relief valve body of  claim 1 , wherein the expanding nozzle includes a nozzle bulb, a nozzle exterior surface, and a valve seat. 
     
     
         3 . The relief valve body of  claim 2 , wherein the nozzle bulb defines a substantially protrudent shape that protrudes away from the axis. 
     
     
         4 . The relief valve body of  claim 2 , wherein the first ramp and the second ramp wrap around opposite sides of the nozzle exterior surface. 
     
     
         5 . The relief valve body of  claim 1 , further comprising a redirecting pallet arranged downstream from the inlet. 
     
     
         6 . The relief valve body of  claim 1 , wherein the first terminal point and the second terminal point are arranged between the axis and the outlet. 
     
     
         7 . The relief valve body of  claim 1 , further comprising an arced portion and a flat portion adjacent to the outlet. 
     
     
         8 . A relief valve body arranged between an inlet and an outlet, the relief valve body comprising:
 an expanding nozzle extending along an axis;   an interior surface arranged downstream of the expanding nozzle and including a first ramped portion and a second ramped portion, the first and second ramped portions ramping from an apex toward the outlet around opposing sides of the expanding nozzle; and   a redirecting pallet arranged downstream of the expanding nozzle and configured to direct fluid flow away from the axis and toward the interior surface.   
     
     
         9 . The relief valve body of  claim 8 , wherein the expanding nozzle includes a nozzle bulb, a nozzle exterior surface, and a valve seat. 
     
     
         10 . The relief valve body of  claim 9 , wherein the nozzle bulb defines a substantially protrudent shape that protrudes away from the axis. 
     
     
         11 . The relief valve body of  claim 8 , further comprising an arced portion and a flat portion adjacent to the outlet. 
     
     
         12 . The relief valve body of  claim 11 , wherein the arced portion defines a decreasing flow area for fluid traversing toward the outlet. 
     
     
         13 . The relief valve body of  claim 8 , wherein the redirecting pallet defines a curved portion and a flat portion that cooperate to direct fluid flow towards the interior surface. 
     
     
         14 . A relief valve body arranged between an inlet and an outlet, the relief valve body comprising:
 a nozzle extending along an axis and defining a nozzle expansion region and a nozzle bulb arranged downstream of the nozzle expansion region, the nozzle bulb protruding away from the axis; and   an interior surface arranged downstream of the nozzle and including a first ramped portion and a second ramped portion, the first and second ramped portion ramping from an apex toward the outlet around opposing sides of the nozzle, wherein a fluid flow area traversed by fluid flowing from the inlet toward the outlet is initially expanded by the nozzle expansion region and is subsequently expanded by the first and second ramped portions.   
     
     
         15 . The relief valve body of  claim 14 , further comprising an arced portion and a flat portion adjacent to the outlet. 
     
     
         16 . The relief valve body of  claim 15 , wherein the arced portion defines a decreasing flow area for fluid traversing toward the outlet. 
     
     
         17 . The relief valve body of  claim 14 , further comprising a redirecting pallet arranged downstream from the nozzle. 
     
     
         18 . The relief valve body of  claim 17 , wherein the redirecting pallet defines a curved portion and a flat portion that cooperate to direct fluid flow toward the interior surface. 
     
     
         19 . The relief valve body of  claim 14 , wherein the nozzle expansion region defines a substantially frusto-conical shape. 
     
     
         20 . The relief valve body of  claim 14 , wherein the nozzle expansion region defines an expansion ratio R exp  of between about 1.5 and about 2.1.