How to efficiently remove varnish from your system

How to efficiently remove varnish from your system

In YouTube video, “How to efficiently remove varnish from your system”, HYDAC shows viewers how to maintain clean oil filters via its varnish elimination unit (VEU) as well as extend the lifetime of fluid, filters, and components.

Oil oxidation products, also referred to as varnish in hydraulic and lubricating systems, can result in malfunctions and increased operating temperatures. This has the unwanted effect of unplanned downtime and high maintenance costs.  

Oxidation describes the reaction of base oil with oxygen.  

There are a variety of catalysts that speed up this process. Contaminants, electrostatic discharges, and burning of oil are the biggest contributors to the formation of varnish.  

Varnish can build up sludge in different areas throughout a system, resulting in problems such as sticking valves, reduced cooler efficiencies, and premature blocking of filters. 

Due to increasing industrial demands, the life expectancy of oil now relies heavily on implementing correct maintenance strategies. Classic techniques include particle filters and water removal through vacuum dehydration.

Currently, there is increased focus on the removal of oil degradation products. 

Identification of oil varnish

Varnish can be identified through laboratory oil analysis. 

One technique is particle counting at different temperatures, which allows measurement of the varnish molecules as they dissolve. 

Another option is the MPC test, which is widely used in turbine applications and involves measuring the colour of these insoluble contaminants. 

HYDAC varnish elimination unit for clean oil filters

Varnish elimination unit (VEU) for clean oil filters

Conventional oil filters are multi-layered, allowing for increased efficiency of particulate removal. However, when it comes to varnish removal, the surface of these filters becomes blocked, which renders them useless. In extreme circumstances, the lifetime of these filters can drop to just a few hours.  

To combat this costly dilemma, HYDAC developed a bespoke solution: the varnish elimination unit (VEU). 

By cooling the oil this innovative technology separates the undesirable oxidation products out, returning the oil to its varnish-free state.  

HYDAC’s VEU continually runs alongside a system, ensuring varnish build is eradicated whilst also extending the lifetime of fluid filters and components. It helps to prevent costly oil changes, unplanned downtime, and the premature replacement of costly system components by curing as much as 40,000L of oil in as little as two weeks. 

In most cases HYDAC’s VEU pays for itself within one year of installation, making it a cost-effective system maintenance choice. 

To watch the video visit HYDAC's homepage, click the YouTube icon at the bottom, and search for “How to efficiently remove varnish from your system”.

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