Dorot S100 QR Series Cast Iron Hydraulic High Pressure Quick Relief Valve with Relief Pilot

The Dorot S100 QR Series High Pressure Quick Relief Valve with Relief Pilot is a diaphragm-operated, hydraulically controlled valve engineered to provide immediate pressure relief in high-pressure irrigation, filtration, and water distribution systems. Designed to protect pipelines, pumps, and system components from sudden surges or overpressure events, this valve opens instantly when pressure exceeds a preset value and closes smoothly once safe conditions are restored.

Constructed from high-strength cast iron and rated for pressures up to 25 bar (360 psi), this high-performance valve is equipped with a spring-loaded relief pilot that continuously monitors line pressure. When the system exceeds the setpoint, the pilot triggers the valve to open—venting excess pressure safely to atmosphere or return lines.

The S100 QR High Pressure model is ideal for critical points in hydraulic networks such as pump discharges, filtration manifolds, and elevation-induced pressure zones, where fast-acting protection is essential.

FEATURES

• Function: Quick pressure relief for system overpressure protection
• Operation: Pilot-operated hydraulic quick relief
  
• Pilot Type: Adjustable spring-loaded Relief Pilot
• Available Sizes: DN25 to DN150 (1" – 6")
  
• Max Fluid Temperature: 60°C (140°F)
• End Connections: Threaded, Flanged
• Body Material: Cast Iron 
• Bonnet: Cast Iron 
• Diaphragm: Reinforced Natural Rubber (optional: NBR, EPDM, Neoprene)
• Spring: Stainless Steel 302 
• Coating: Polyester Epoxy, Rubber, or Nylon
• Relay Valve Manual Override: Built-in 3-position selector

BENEFITS

• Instantly opens to release excess pressure and protect system components
• High-pressure design suitable for demanding installations
• Smooth closing action prevents water hammer and secondary surges
• Relief pilot allows easy setpoint adjustment and accurate pressure control
• Fully hydraulic—no power or electronics required
• Heavy-duty cast iron body with corrosion-resistant coating
• Ideal for pump protection, filter stations, and pressure-critical pipelines