Accession Number:

AD0871991

Title:

Deposition and Degradation Characteristics of Aircraft Turbine Engine Lubricants. Volume I.

Descriptive Note:

Technical rept. 1 Feb-1 Dec 69,

Corporate Author:

SOUTHWEST RESEARCH INST SAN ANTONIO TX

Personal Author(s):

• Barber, B. B.
• Cuellar, J. P.
• Montalvo, D. A.

Report Date:

1970-06-01

Pagination or Media Count:

84.0

Abstract:

A detailed description of the bearing deposition test method for evaluating deposite and degradation characteristics of aircraft turbine engine lubricants at various temperature severity levels is presented. The 350500F bearing deposition test data are presented for 103 lubricants, identified generally as MIL-L-7808 and MIL-L-23699 type lubricants. Approximately 40 percent of the lubricants evaluated at these test conditions gave a deposit rating of less than 60. Lubricant O-68-10, a MIL-L-7808 type lubricant, gave the lowest mean deposit rating, 18, of all the lubricants evaluated. Analysis of the results shows that one to three tests, depending upon the value of the mean deposit rating, are generally required to obtain reasonable confidence in the mean deposit rating. No evidence of incompatibility, with respect to deposit ratings or degradation characteristics, was noted for 30 lubricant blends evaluated. The need for an improved test bearing heater mount design which will provide improved temperature distribution on rated surfaces became evident when temperature spreads of approximately 100F or more were measured on the rated surfaces during routine 350500F bearing deposition tests. Author

Descriptors:

• *GAS TURBINES
• *AIRCRAFT ENGINE OILS
• LUBRICANTS
• TEST METHODS
• DEPOSITS
• DEGRADATION

Subject Categories:

• Lubricants and Hydraulic Fluids
• Jet and Gas Turbine Engines

Distribution Statement:

APPROVED FOR PUBLIC RELEASE