Rotary Airlock / Rotary Air Valve


Rotary air locks, as the name suggests, acts as a seal (locks out “false” air) while moving the material from the inlet to the outlet due to continuous rotation. The rotary air lock maintains a constant pressure (or vacuum) difference between the inlet & outlet port whilst moving material continuously.

Rotary air lock, rotary air valve, rotary valve, RAL, RAV, rotary feeder.

The rotary airlock has 3 main components – housing, rotor & drive arrangement. The rotor is the moving part of the RAL. The rotor generally has 8 blades & closed ends. The RAL is primarily material handling equipment &is subjected to wear & abrasion. The proper selection of RAL for an application depends on flow rate, nature & characteristics of material being handled.

Wear, due to abrasion, from a material being handled through RAL can be divided in 2 categories – surface drag abrasion & pneumatic assisted abrasion. Surface drag abrasion is created by moving or pushing an abrasive material.Wear also occurs due to abrasion created by “false / blow-by” air developed at the outlet port when used on pressured pneumatic system. This “false / blow-by” air provides the force behind pneumatic assisted abrasion. The characteristics & flow rate of the material being handled, pressure difference & sealing efficiency
are used to decide the size & material of construction of the RAL. Proper selection will reduce down-time & help drive process performance.

The components of the RAV are fabricated & assembled. The rotor is checked to ensure that it moves freely in the housing. The motor is then coupled to the rotor. The RAL assembly is operated with motor to check for vibrations & noise. Various parameters such as pressure drop, rotor speed, etc. are measured & recorded.