HPFlap, Inc.
HPF, Inc.
13540 Indian Creek
Cleveland, Ohio 44130
Tel: 440-816-2195
Fax: 440-816-2196

Pneumatic Level Detection

On this page are shown two different types of Pneumatic Overfill Device both specially designed to give dependable and safe operation in open tank top loading. Both systems basically operate by the following method.

The pneumatic circuit continually bleeds a small flow of air out through the sensing tube (connected to the Drop Pipe). When the liquid level in the tank reaches the end of the sensing tube, the air signal is amplified by the air logic control giving either overfill alarm or shut-off. As the air flow continually purges the sensing tube, liquid and vapours cannot enter the system which is completely independent of product flow rate, pressure or temperature.

Model 2794 - Pneumatic Overfill Alarm

When the sensing tube is submerged by 2-3 cm the amplified back-pressure closes (or opens) an EEx-d electrical contact, for connection to site alarm or pump. The air logic control is automatically reset when the sensing tube is withdrawn from the liquid.

Required air pressure : 3 - 5 Bar
Air consumption : 1.5 nl / min.


Model 3013 - Pneumatic Overfill Shut-Off

Loading valve is operated by pneumatic actuator controlled by push button. The Loading valve shuts off when the sensing tube becomes submerged. Automatic system reset on withdrawal of the sensing tube from liquid. In addition the Loading valve or ball valve will also close in the event of air failure as a safety precaution.

Required air pressure : 5 - 6 Bar Air consumption : logic control 1.5 nl / min : valve actuator 1.5 nl / per cycle

© 2006 HPF, Inc.    Home  .:.  Contact  .:.  Policies