Piston Safety Relief Valve
Resistant
Sealing
Operation
Long Life
Piston Safety Relief Valve is designed to protect pressure systems from overpressure by automatically relieving excess pressure when it exceeds the set pressure. It is suitable for boilers, pressure vessels, pipelines, water systems, process plants, and industrial applications.
Specifications
Size Range
DN15 to DN100 (½" to 4")
Set Pressure
As per system requirement
Body Material
Carbon Steel / Stainless Steel / Cast Steel
Seat Material
PTFE / Metal Seat
Pressure Rating
PN16, PN25, PN40 / Class 150–300
Operating Temperature
Up to 200°C*
Piston Material
Stainless Steel / Alloy Steel
Discharge
Open / Closed Discharge
Product Images
Frequently Ask Questions
A Piston Safety Relief Valve automatically releases excess pressure when system pressure reaches the preset relief pressure.
Its primary purpose is to protect pressure-containing equipment and piping from excessive pressure.
The valve must be capable of discharging enough fluid to prevent system pressure from exceeding the permitted limit.
Set pressure is the pressure at which the valve is intended to open, while operating pressure is the normal pressure of the system.
Yes, but the valve must be correctly sized and configured for the specific medium and relieving conditions.
When system pressure exceeds the set pressure, the piston moves against the spring force and opens the discharge passage to relieve excess pressure.
Blowdown is the difference between the set pressure and the pressure at which the valve closes after relieving excess pressure.
An undersized relief valve may not provide sufficient relieving capacity, potentially allowing pressure to remain above the safe limit.
Back pressure can affect the opening and closing behaviour and relieving capacity of the valve, so it must be considered during selection.
Yes, ALIS Valves is a Piston Safety Relief Valve Manufacturer in India, offering pressure-relief valve solutions for industrial pressure protection applications.