New Test Method for Accelerated Oxidation Test to Evaluate the Oxidation and Deposit Control Performance of Turbine Oils
1. Scope
This test method covers the evaluation of the oxidation stability of inhibited turbine oils in the presence of oxygen, and copper and metal catalyst (copper and iron) at an elevated temperature. This test method is limited to a maximum testing time of 10,000 h. This test method is also used for testing may be used to evaluate industrial oils (for example, circulating oils and so forth).
Keywords
turbine oils; oxidation stability; deposit control; varnish potential; dry-air oxidation; copper/iron catalysts; accelerated aging; condition monitoring; antioxidant depletion; MPC; patch colorimetry; RULER; RPVOT; TOPP
Rationale
The Thermal Oxidation Performance Protocol (TOPP) is proposed as a distinct method because it addresses the need for accelerated and reproducible aging assessments that incorporate deposit-control metrics rather than relying solely on sludge evaluation. TOPP uses controlled thermal-oxidative stress conditions and applies endpoint-based termination criteria, such as viscosity increase, acid number, deposit rating, and other guideline recommendations as specified in ASTM D4378, to accommodate formulation differences and support risk management. This approach ensures that oxidation stability testing reflects performance requirements and provides actionable insights for lubricant development.
The title and scope are in draft form and are under development within this ASTM Committee.
Work Item Status
Date Initiated: 12-22-2025
Technical Contact: Douglas Purnell
Item: 000
Ballot:
Status: