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25 October 2023: Wear control specialist ISO-Reliability Partners manufactures products that have gained wide acceptance among power plants, steel mills, refineries, mines, and other industrial facilities with rotating equipment. Its vacuum dehydrator and oil purification system assists companies to reduce operating costs by improving machine reliability, safety, performance, and production, explains Craig FitzGerald.

The system is highly effective at removing dissolved, free, and emulsified water, entrained gas, and particulate contamination for heavy and light gear oils of any grouping. The overall water content can be reduced to levels below the water solubility point in the oil simply by using a vacuum dehydrator. Heat transfer oils used in concentrated solar systems can also be rejuvenated with the ISO-Reliability vacuum dehydrator and oil purification system.

By raising the oil temperature to approximately 50°C and passing it through a vacuum chamber, water turns to steam. Even water that is tightly held in an emulsion is removed, along with any free and dissolved water. “Our systems are equipped with high efficiency filter elements that remove particulate contamination and entrained gases to ultra-low levels,” highlights FitzGerald.

Water moisture can find its way into lubricated components in liquid or gaseous forms, this enters via seals, bulk reservoir breathers, and general storage of equipment. Its interaction with oil is harmful as it only takes a small amount of water (less than 500 ppm) to substantially shorten the service life of rolling element bearings. Water is the start of corrosion; it gives acids their greatest corrosive potential. Static etching and fretting are also accelerated by free water. Water further promotes foaming, which leads to rapid increases in metal-to-metal contact, friction, and higher temperatures. As a result, water reduces the lubricant’s ability to lubricate.

Foaming leads to sluggish response from hydraulic control systems and cavitation in pumps and bearings. Moisture in a lubricating oil or diesel presents an opportunity for microbes to thrive and grow. Microbes live in the water and feed off the hydrocarbon. They grow to interfere with lube circuits and can block valves and filters. Microbial contamination is corrosive and can be toxic.

The presence of water in a bearing load zone produces superheated steam which creates a mini explosion inside the oil, similar to micro-dieselling in hydraulic systems. Through oxidation, this phenomenon rapidly damages the oil and hardened fatigue cracks appear on bearing surfaces. What’s more, the presence of water can hydrolyse additives like extreme pressure and anti-wear, essentially denying equipment the protection that the additives are designed for.

The by-product is sludge water, which is similar to other contaminants in the lube oil such as soot, resin, spent additives, oxides, and dirt. These cluster into a sludge that will overwhelm strainers, in-line filters and eventually restrict oil flow in the system. A value of 0.1% (1,000 ppm) water in oil will reduce the life of a rolling element bearing by as much as 40 times. As moisture is absorbed into the lubricating oil, it affects the lubricant’s film thickness and ability to separate lubricated components.

FitzGerald adds that many companies have funds readily available in their maintenance budgets to purchase or rent a vacuum dehydrator onsite for emergency use or for scheduled maintenance. Similarly, many clients engage an expert like ISO-Reliability Partners that specialises in oil reclamation and purification to perform the dehydration service on-site with class leading technologies and unmatched ISO cleanliness results.