8. Compressed air fail: Compressor lubricant release
A food products company used lubricated screw compressors to feed the process machines in their plant. The compressors contained food grade lubricant because some of the compressed air came in contact with the product.
The lubricant is an important item within the compressor, acting as a lubricant, a coolant, a medium to capture contaminants and water, and a method to seal the gap between the screw elements. Lubricated screw compressors rely on an oil separator to filter the compressor lubricant from the stream of compressed air produced by the screw element. This separator, when working properly, will filter all but a few parts per million of oil particles. The remaining lubricant must be removed by downstream components.
The food products company maintained a tight maintenance budget and minimal staff to save costs. As a result, the recommended maintenance frequency of lubricant and filters were not followed for their air compressors. Due to neglect, there was a catastrophic failure of one of the oil separators in their oldest compressor. When this happened, the air compressor emptied its complete supply of lubricant into the system.