AD402 Auto Drain Valve

OLKAD402 auto drain valveAutomatically and reliably discharges drainage without the need for manual operation. Dust- and corrosion-resistant for long-lasting performance, with a durable bowl guard included as standard.Designed for efficiency, built for reliability!

AD402 auto drain valveWorking Principle:

1.No Pressure in the Bowl:

   When there’s no internal pressure, the float drops due to its weight, sealing the chamber hole. The piston is pushed down by a spring, and drainage flows through an elongated hole to the housing, where it’s discharged.  

2.Pressure Applied to the Bowl:

   When internal pressure exceeds 1 MPa, it overcomes the spring force, lifting the piston until it seals against the O-ring. This isolates the inside of the bowl from the outside.  

3. Drainage Accumulation:

   As drainage collects, the float rises, opening the chamber hole and allowing pressure to enter. This pressure, combined with the spring force, pushes the piston down, discharging the drainage through the drain guide.  

Notice

1: When installing drainage pipes, use pipes with an inner diameter of more than 10 millimeters and a length not exceeding 5 meters. Do not bend the pipes upwards.

2. The compressor power should be greater than 3.7kw

SMC type AD402 series auto drain valveGeneral parameters