Soluble and Insoluble Varnish Test Methods for Trending Varnish Buildup in Mineral Turbine Oil

Varnish problems in turbine oil of power plants Thailand are still an issue today. The the coefficient friction will increase along with varnish concentration and deposits. This creates starting/re-starting turbine. Even advent manufacturing research to improve base quality antioxidant additive, contamination starting have been one most concerning for maintenance. recent version ASTM D4378-20 suggests that maintenance personnel should test their in-service monitor membrane patch colorimetry a warning limit at ∆E 30. monitoring is known as D7843-20 Standard Test Method Measurement Lubricant Generated Insoluble Color Bodies In-Service Turbine Oils using Membrane Patch Colorimetry (MPC). study introduces soluble color bodies, addition insoluble, same time. Focusing only on value insoluble-MPC can sometimes be misleading may cause inaccurate ineffective decisions. In this paper, both insoluble body analytical results from gas oils presented. Three were monitored varnish. It show how use combination assessments would further diagnostic services lubricants by providing insights into capability solubilize oxidation by-products antioxidants highly refined oil. Appropriate removal technologies also decided applied respond proactively issues.