Patent ID: 11959557
Assignee: DRESSER, LLC
Field: Mechanical elements (Mechanical engineering)
Classification: CPC F | IPC F

Claim 0:
1. A pilot-operated safety relief valve, comprising:
a valve body with flanged openings for connecting to pipes;
a coverplate coupled to the valve body so as to enclose a space inside of the valve body;
a port, separate from the flanged openings, which is coupled with the space;
a moveable piston disposed in the space and moveable along a movement axis, the moveable piston having a first part and a second part stacked on the first part and separable from the first part;
a guide having a central bore that receives the first part of the moveable piston;
a first spring having a first end and a second end, the first end of the first spring in contact with a surface of the second part of the moveable piston and the second end of the first spring in contact with the guide;
a second spring having a first end and a second end, the first end of the second spring in contact with a surface of the first part of the moveable piston and the second end of the second spring in contact with the guide; and
a pilot valve coupled with the port,
wherein the first spring generates a load in response to a decrease in pressure in the space that causes the second part to move to evacuate fluid from the space into the port.