By Ron Marshall for the Compressed Air Challenge
A metal products manufacturer was well aware of the benefits of large storage receivers installed on its system of load/unload compressors. The receivers act as a quiet zone where water and lubricant can settle out of the air before entering the system dryers. In this zone, the air is cooled—making it easier to dry. And the significant storage reduces the compressor’s load/unload cycle frequency, which reduces the energy consumed.
The processor purchased a 1,060-gal storage tank, which was placed on the wet side of his refrigerated air dryer. All was well for many months until the maintenance personnel noticed the compressors cycling excessively. The air dryer was also performing poorly, allowing water into the downstream piping, fouling air-operated tools.
An experienced auditor was called in to take a look at the system. After checking the compressor settings, the dryer and filter differential, and examining the piping, he had a look at the wet receiver condensate drain. For some reason, the automatic drain had failed. A manual valve was opened—and about 1,000 gal of water was released after draining the tank for what seemed like hours. A failed drain had caused the tank to completely fill with condensed water over a period of time, making the receiver ineffective in improving the system. The free water that gurgled out was overwhelming the air dryer.
The plant engineer was concerned, as the completely full tank was extremely heavy and could have caused mounting structures to collapse. The drain was replaced and compressor operation returned to normal. The plant now has a regular maintenance schedule to test the drains.
Learn more about condensate drains in our next Compressed Air Challenge seminar in your area. Visit www.compressedairchallenge.org for more information.
William K. says
It is hard to imagine why a device to monitor the water/condensate level was not included in the installation described. Any system that is likely to have condensate needs to have a monitored draining arrangement. I once saw a very inexpensive and yet very effective system in a small plant which used a time switch to do the blow-off enable. The air blast sound doubled as the end-of-shift announcement, and so it was monitored by the whole production floor. Any changes in the sound were immediately reported. A very effective and inexpensive monitoring scheme.
JOHN KEIGHTLEY says
We leave the condensate drain cracked open so it is always draining – the small leak is insignificant compared to the overall air consumption