What are pilot-operated valves?

Pilot-operated valves are pressure relief valves that control the main valve’s inlet and outlet port. They are similar to spring-loaded valves but are the best alternative solution for reaching the highest pressure and highest capacity. These valves offer excellent performance for overpressure protection. This valve type was initially recognized as a unique solution to withstand high backpressure or improve system stability, but its outstanding capability to optimize valve selection is often overlooked. Due to their compact design, these valves are typically used in the oil and gas industry, especially upstream in offshore applications.

How pilot-operated valves work

Any pilot-operated valve is designed to withstand higher backpressure than a spring-loaded valve. The main valve piston is protected by the guide and balanced without having any fragile components that are prone to fail. The main valve has the same pressure at the inlet and on the dome—the dome is the upper part of the main valve, and due to sectional area variation, drawback force is applied on the piston. The pilot opens when you increase the pressure and reach the set point. It disconnects the upper part of the piston. The pressure is a direct vacuum to the atmosphere, making the piston open and relieving the main valve’s total capacity.

However, when several valves are connected to the same flare, the superimposed backpressure can exceed inlet pressure, and the upward force generated can open the main valve prematurely. It works with the main valve, which the pilot controls. As pressure is transmitted from the main valve inlet to the dome chamber through interconnecting tubing, a positive load is exerted on the main valve disc. This loading is due to the 30% larger dome seal area relative to the inlet seat.

The benefits of pilot-operated valves

Pilot-operated valves are the ones to go with when you have a significant pressure drop for its capacity to modulate. Many accessories can connect to a pilot valve as it is significantly easier than a spring-loaded valve. It also has a better size and pressure capability than the spring-loaded valves. The pilot-operated valves can be directly connected to your vessel using a static or remote sensing line. The pilot controls the main valve and allows it to keep its open position whatever the pressure drop at the inlet.

What makes Trillium’s choke valves different?

Trillium Flow Technologies manufactures a complete range of application-specific pilot-operated pressure relief valves. They are the most advanced pilot-operated valve design to provide tight shut-off at 98% set pressure. These valves ensure minimal product loss, avoid oversizing consequences, and reduce environmental pollution in any industry relief situation. We provide exceptional service and solutions to meet the changing market needs by expanding pilot-operated capabilities, making them an undisputed pressure relief solution provider for any industrial application.