"What are the best practices for oil mist systems?"
Oil mist systems should aid in the reduction of oil waste generation while improving equipment reliability. The majority of systems require little maintenance or inspection for hassle-free operation. However, when dealing with an oil mist system, it is important to understand the makeup of your system and how it operates. You must also ensure the system is selected correctly and installed properly.
Oil mist generators should be placed approximately within a 600-foot radius of process pumps. The first 50 feet of supply piping must be sloped back toward the mist generator so any excess oil runs back to the sump to decrease waste. All other piping should be sloped back toward the mist generator or sloped to low spots with a drain port. Any pooling spots provide a potential area for oil mist to collect and trap the oil.
Oil droplets should be in the range of 1 to 3 microns with an oil-to-air ratio of 1-to-200,000. Oil mist should be in the range of less than 1 pound per square inch (PSI) with a low velocity to prevent droplets from colliding and coalescing into larger droplets before reaching the lubricated components.
It is also critical to select the right reclassifier. Remember, if a little oil is good, a lot of oil is not necessarily better.
Common components of an oil mist system include an air filter, separator, regulator, air heater, oil reservoir, oil reservoir heater, supply piping, reclassifier or mist fitting, collection tank and vent piping. These items should all be inspected for periodic maintenance.
Air filters and air separators must be checked and cleaned so a clean supply of air is delivered to the system. The air heater and tank heaters also should be checked for proper operation. Tank heaters should operate around 170 degrees F to guarantee correct atomization of the oil. In addition, don’t forget to check and refill the tank level of the oil reservoir system as needed.
Collection tanks must be inspected regularly to prevent oil pooling and backing up the system. Also, periodic checks of all piping and pumps should be performed to identify any stray misting from piping or seals.
Finally, be sure to follow the four "Rs" of lubrication — using the right oil in the right amount in the right place and at the right time. If properly selected, installed and maintained, oil mist systems can provide decades of dependability and reliability.
