With the introduction of turbine oils using Group II base oil technology, varnish has presented itself as one of the most prevalent issues facing turbomachinery equipment operators today. While ion resin exchange filtration solutions providers and chemical detergent manufacturers have scrambled to offer solutions to combat existing problems with varnish, it wasn’t until recently that a major oil company, Chevron Lubricants, developed a two part solution that uses the same technology used to remove varnish deposits to also prevent future varnish formation.
What is Varnish?
In the simplest terms possible, varnish is produced when oxidation byproducts deposit on to a surface. With regards to a turbine, compressor, or hydraulic system, the surfaces that varnish often forms on include:
- Valves
- Bearings
- Orifices
- Pumps
- Filters
While decreased lubricant life and varnish deposits are some of the most obvious symptoms of varnish, there are several problems that will indicate that you have a problem with varnish in your turbine, compressor or hydraulic system. You can also use oil analysis to detect if you have a problem with varnish.
Problems Caused by Varnish
- Journal bearing failures – Varnish prevents oil from performing most of its lubricant functions including; cool surfaces, prevent wear, prevent oxidation, and transfer contaminants to filters, leading to bearing failures.
- Filter Plugging – Once the solvency of a lubricant is lost, filters will quickly begin to plug with degradation byproducts such as varnish.
- Flow Restriction – Not only will filters begin to plug but varnish deposits will begin to restrict flow in small orifices and strainers.
- Restriction and sticking of moving parts – such as servos, directional valves, and other mechanical parts.
- Component Wear – Varnish does a great job of attracting hard particles and causing them to stick to the surface of lubricated components. This will promote component wear.
- High Bearing Temperatures/System Tripping – Varnish has a thermal insulating effect on metal surfaces, especially bearings where the oil is intended to not only lubricate but dissipate heat from the surfaces of the bearings.
- Decreased Oil Life /Oxidation – Varnish is an auto-catalytic reaction that leads to accelerated oxidation and loss of an oil’s useful life.
Chevron’s Holistic Approach to Tackling Varnish
Chevron’s VARTECH™ Industrial System Cleaner (ISC) + GST Advantage™ RO
While lubrication services providers have always been happy to remove varnish with a combination of a chemical clean and high velocity oil flush, this method is extremely expensive and inefficient. Additionally, compromising the integrity of the final fill oil additive package is something to be concerned about when using certain chemicals.
Chevron Lubricants developed VARTECH™ Industrial System Cleaner (ISC) in order to create a holistic approach to not only removing varnish deposits, but also preventing them by including this chemistry in their new GST Advantage RO™ Turbine Oil.
Click here to learn how IFM can use VARTECH™ ISC to tackle varnish in your equipment.
Chevron VARTECH™ ISC
Chevron VARTECH™ ISC is a deposit cleaning product added directly to the oil in use during operation in order to clean a system of varnish and sludge deposits before a scheduled oil change. It helps prepare the system for optimum performance prior to a new, fresh oil change.
- Stabilizes varnish and sludge surface deposits in the oil to enable their efficient removal through a scheduled oil change, restoring system operational efficiency
- Being solvent free, reducing volatility and seal compatibility concerns.
- Minimal filter plugging
- Excellent compatibility with many compressor and turbine oil products (mineral and synthetic hydrocarbon based)
- Retains oxidation control performance
- Excellent seal compatibility
- Extended cleaning duration times are possible
- Minimal flushing
Click here to learn more about VARTECH™ Industrial System Cleaner (ISC)
Chevron VARTECH™ ISC
Chevron GST Advantage RO w/ VARTECH™ ISC
GST Advantage™ RO products are formulated with VARTECH™ Technology, which is advanced chemistry combined with premium base oils that inhibits varnish formation to help maintain peak performance, reliability and productivity.
- Low Varnish Potential ensures varnish formation is minimized to extend oil life and protect equipment.
- Exceptional Oxidation and Thermal Stability for long service life at severe temperatures with minimal deposit formation.
- Outstanding Rust and Corrosion Protection
- Minimum Foaming helps prevent sump overflow or erratic governor operation.
- Fast Air Release minimizes possibility of pump cavitation in systems with high circulation rates and lesser residence time.
- Rapid Water Separation facilitates water removal.
- Hydraulic Fluid Service for systems requiring an ISO viscosity grade 32 or 46, and pressures not exceeding 1000 psi.
Click here to learn more about Chevron GST Advantage RO.
Chevron GST Advantage RO
