AKO Pressure Relief Pinch Valves Protecting Pumps & Motors From Damage

AKO pinch valves are becoming more and more popular for protecting pumps and motors from damage.

The AKO Pressure Relief Pinch Valve is fitted onto a bypass line of a pump. The valve is then charged with air and set closed at the pressure it is required to relieve at. If the associated pump becomes clogged or blocked, causing the line pressure to exceed the pressure at which the valve is set closed at, it will open allowing the product to bypass the pump equalizing the pressure until the blockage is cleared. When the blockage is cleared the valve will reset itself in its ‘closed’ position to the original set pressure.

Conventional spring-operated globe-type valves have always been popular for most pressure relief duties, but in some applications the spring can easily become clogged with ‘difficult’ products being pumped; and the result is a pressure-relief bypass line that constantly fails to close properly.

Experience has shown that spring-operated relief valves require an operational tolerance band which is significantly wider than that required by the AKO Pressure Relief Valve. Consequently, in some installations the higher risk of damaging a pump or its drive motor because the spring fails to act at the correct pressure, this leads to the use of the AKO Pressure Relief Valve, which are considerably more reliable in their operational threshold.

At a sewerage treatment plant four 150mm progressive cavity pumps are used to move sludge between treatment tanks during the water-recovery process. Each pump is equipped with a simple bypass controlled by an AKO Pressure Relief Valve. Kept normally-closed by an air pressure of 6 bar, the pinch valves are only forced open if the sludge pressure in the line builds up either by someone closing a downstream valve, or due to a blockage caused by the heavy solids content of the sludge. Once the line pressure exceeds 6 bar, the sludge effectively forces open the pinch valve by back-pressure. Once open, the pinch valve allows sludge to flow into the bypass, back to the suction end of the line-thus equalizing the pressure and protecting the pump.

A foot pump or small battery operated compressor can be used to charge the pinch valve when the valves are being used in remote locations where compressed air is not available.

The valves can also be fitted with an IP65 Pressure Switch. The optional switch has two switches inside a single housing. It is set so it will send a rising signal when the valve is relieving or a falling signal if there is a problem with the valve. The electrical signal can be sent to a local starter or PLC Control to stop the pump or open/close other valves on the system until the problem is rectified. An alarm or telephone alarm can also be sent to alert operators that maintenance is required.

Other important advantages of the AKO Pressure Relief Valve include: clear and true bore meaning no blockages or friction, no mechanical parts to get clogged or blocked and single body casting meaning no chance of leaks.

The AKO Pressure Relief Valve is proving to be the best and most cost effective solution to protect pumps and motors from over pressure and damage.

For information on AKO pressure relief pinch valves email us at info@c2c.co.nz or if you would like to discuss a particular application phone us on 09 535 6677.