Do you Need Assistance?

Contact our Technical department if you need more information.

+98 (21) 56804700

  • Mirab Co.

Large Orifice Air Valve

Size (mm) : 200-1000
Pressure rating : 10-63 (bar)
Body Material: All Types of Ductile Cast Iron, Cast Steel, Stainless Steel, Copper Alloys
Float Material: All Types of Stainless Steel

Large orifice Air Valve is recommended as part of safety system for large diameter and long length pipes. Under normal conditions (positive pipeline pressure) this Air Valve is fully closed, it serves as vacuum breaker when the internal pressure in the pipe drops to negative value. For example in case of pipe burst situation with very rapid medium drainage , a huge volume of air is inserted to the pipe through the large orifice of the Air Valve to prevent damages or crumple of the pipes. After pressure increases in the pipe line, the air valve will be closed again. A pneumatic damper is located in the valve for adjusting valve closing speed to avoid damages in the pipe or valve due to rapid closing.

Paint Coating :
Electrostatic epoxy powder (RAL 5005 or 5015) with min. thickness 250 micron.

This valve is applied to transmit large amount of air into water pipeline in critical situation (e.g. pipeline burst). One of the important applications is using this air valve after emergency shutdown valves.

Product features:
• Valve disc starts to open when fluid pressure drops to -0.1 bar
• Valve disc completely opens when fluid pressure drops to -0.2 bar
• Producible in large and pressure up to 63 bar
• Equipped with single chamber air valve