How to Improve Vacuum Efficiency For Packaging Applications

How to Improve Vacuum Efficiency For Packaging Applications

Tony Greenly | July 11th, 2018

Vacuum applications can be prone to inefficiencies and, therefore, waste a lot of energy. If you have a “dumb” or under-sensored process, you may as well count the dollars as the air blows through the exhaust of a venturi! Inefficiencies are a fact of life with vacuum applications, but there is a way to safeguard your investment. Here is an example of how Cross Company implemented a Coval LEMAX, which turns on/off the air flow to the venturi based on sensor readings.

A Vacuum Packaging and Loading Application

During a site visit, our customer took me to their R&D room to show me an application they were working on. When I walked through the door I saw a nest of air lines running all over the place attached to vacuum sensors, blow off modules, vacuum venturis and pneumatic valves. The task he was attempting to complete was a case-fill operation on a conveyor. An empty corrugated container was traveling down a conveyor and stopped at a predetermined location. An arm with two vacuum cups swung out to grip the flap for case-filling. Once the packaging was complete, the vacuum released, and the container moved forward for taping.

We discussed some options for tube management and for sizing the components correctly. During our conversation, he mentioned that his customer is very air conscious and this got me thinking. He said the desired operation was to shut off the air flow supply when a vacuum was met and to have a blow-off circuit to prevent residual vacuum. One neat side effect of using a blow off was that it put the lids in a more advantageous position for the flap closure.

Coval LEMAX Provides Process Efficiency

Once I was able to understand the full breadth of what he was looking for, the first product to jump into my mind was the LEMAX by Coval. It had all of the features they wanted, especially increased efficiency. This is achieved by a vacuum switch and a small valve internal to the unit. Once 65% of the vacuum is met, the sensor knows there is a part present. At 75% of the vacuum met, the valve turns off and relies on the vacuum in the cup. If there is a tiny leak and the vacuum drops below 65%, the sensors know to turn on the valve and increase vacuum again. All of the vacuum set points and hysteresis are adjustable so for instance, if you’re picking up a delicate slip sheet, the vacuum can be adjusted not to destroy the sheet.

Coval LEMAX is Smart Vacuum Sensing Solution

I went back to my customer for a follow-up visit and showed them the LEMAX smart vacuum pump. We discussed its features and benefits and decided this was the best choice for the operation. They bought eight of these for the line and they have been working flawlessly for a few years now. If you are trying to sense vacuum, need a blow-off, and are concerned about energy usage while keeping it in a nice neat package, consider the Coval LEMAX smart vacuum pump.

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Tony Greenly


Tony graduated from the Center for Automation and Motion Control (CAMC) program at Alexandria Technical College in Alexandria, MN in 2004. He's worked inside and outside sales for distributors for most of his career. Tony has been with Cross Company since 2008 and has become Fluid Power Certified.