Over time, varnish buildup can increase the friction inside hydraulic valves, especially those with fine tolerances. This phenomenon can be especially troublesome in servo and proportional valves by causing erratic operation and equipment malfunctions. The impact of sticking valves on the hydraulic system is impaired responsiveness and reduced oil flow, which results in overall loss of efficiency and increase in maintenance costs.

Lubrizol Corp., Wickliffe, Ohio, recently introduced Lubrizol 6776, an additive that prevents varnish buildup in hydraulic systems. Available globally, it uses Lubrizol’s patent-pending Clean Technology.

“The hydraulics market has created a trend of increasing power output and at the same time smaller fluid reservoirs. As a consequence of these changes, the operating temperatures of hydraulic fluids used in these systems are significantly higher, leading to greater risks of oxidation and thermal degradation of the additives in the fluid. Varnish, the result of that degradation, can result in unplanned downtime, higher maintenance costs and lower profitability,” says Rob Profilet, Lubrizol’s commercial manager of hydraulic and gear oil additives.

Lubrizol’s new Clean Technology package provides:
• prolonged oxidation resistance to help extend oil life and prevent varnish formation,
• high thermal stability to help minimize varnish formation,
• high demulsibility so water separates out quickly,
• outstanding anti-wear protection of system components,
• high-level rust and corrosion protection to help extend component life, and
• excellent filterability, even in the presence of water.

Lubrizol 6776 is particularly suited to hydraulic applications where high temperatures — typically found in mobile equipment, plastic injection molding machines, and glass transfer systems — can be problematic and compromise the oil’s life. It is also suitable for equipment owners who want to extend the life of their oil and their equipment, including valves, filters, and pumps.

To learn more about Lubrizol’s Clean Technology or to obtain Lubrizol 6776 product brochures, e-mail industrial@lubrizol.com.