Combination Air Valve (WSI-AV2Plus-2) - Alwasail Products

Combination Air Valve (WSI-AV2Plus-2)

Combination Air Valve (WSI-AV2Plus-2)

• Main Irrigation Networks – Air relief, protection against air accumulation and vacuum formation downstream of pumps, along supply lines, and at elevations in main irrigation networks.

• Irrigation Control Heads – Air relief, protection against air accumulation and vacuum formation at filtration and fertilization stations, and downstream of main control valves.

• Infield Systems – Protection against air accumulation and vacuum formation in proximity to water meters and automatic regulators.

• Landscape Irrigation – Protection against air accumulation and vacuum formation.

Features & Benefits

  • Straight flow body with large diameter automatic orifice – Higher than usual flow rates.
  • Aerodynamic full-body kinetic shield – Prevents premature closing without disturbing air intake or discharge.
  • Dynamic sealing – Prevents leakage under low-pressure conditions (0.1 bar).
  • The boss on the base can be tapped with a thread for pressure gauge connection, checkpoint, or test drain for air valve function.
  • A compact, simple, and reliable structure whose parts are fully corrosion, chemical, and fertilizer resistant – Lower maintenance and increased life span.
  • Factory approval and Quality Control – Performance and specification tested and measured with a specialized test bench, including vacuum pressure conditions.

Additional Features

  • Surge Protection (anti-slam) – Smoother operation, preventing damage to the valve and the system.
  • Inflow prevention – Prevents intake of atmospheric air in cases where this could lead to damaged pumps, required re-priming, or disruption of siphons.

Pipeline Filling:

  • During the filling process of a pipeline, high airflow is forced out through the kinetic orifice of the air valve.
  • Once water enters the valve’s chamber, the float buoyed upwards causes the kinetic orifice to close. The unique aerodynamic structure of the valve body and float ensures that the float cannot be closed before the water reaches the valve.

Pressurized Operations:

  • During the pressurized operation of the pipeline, air accumulates in the upper part of the air valve chamber, causing the float to gravitate downwards. The automatic orifice opens and the accumulated air is released.
  • Once the air is discharged, the water level and float rise, causing the automatic orifice to close.

Pipeline Draining:

  • When a pipeline is drained, a negative differential pressure is created causing atmospheric air to push the float downwards.
  • The kinetic orifice stays open and air enters the valve chamber, preventing vacuum formation in the pipe.

Surge Protection (anti-slam):

  • The anti-slam device is fitted to the air valve outlet. In the event of a pressure surge, it partially closes the valve’s outlet. The approaching water column decelerates due to the resistance of the rising air pressure in the valve.

Inflow Prevention:

  • Inflow prevention is a normally closed check device fitted on the valve’s outlet and prevents the flow of atmospheric air into the valve.

Technical Specification

Model Max Working Pressure
Sealing Pressure
Air Outtake Flow
Air Intake Flow 
1″ BSP 225 5 280 m³/h @ 0-5 psi -280-0 m³/h @ -5-0 psi

Valve Selection

  • Inlet sizes: ( 1″, 2″)
  • Connections: Threaded Male BSPT

Operational Data

  • Pressure rating: ISO PN 10
  • Operating pressure range: 0.1-10 bar
  • Operating temperature: Water up to 60°

Performance Charts

For more information about this product and its related items, you may check and browse the catalog below:

  1. Landscape Irrigation Products Catalog


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