Low Lubricity Fuel

The use of the pumped fuel as the lubricant for the pump and all components within the fuel system is an established and required practice. Unfortunately, there is no requirement for lubricity in the fuel specifications. Therefore, some knowledge of the minimum lubricity to be expected in the field is necessary. The key factor to determine is the lubricity of the fuel under boundary lubricating conditions for evaluating the wear characteristics of the gear tooth profiles and the fuel lubricated spline teeth. An intensive cooperative industry and government evaluation effort has identified the Exxon ball and cylinder wear test machine as an accurate and reliable method of evaluating the lubricity characteristic of aircraft gas turbine fuels. The pump specification will contain the fuel lubricity level with which the pump will be required to demonstrate operation for its intended service. The pump designer must select gear materials and geometries that are compatible with the specified lubricity level and operating conditions. Wear experienced on low-lubricity fuel is a threshold type of surface failure. Therefore, this threshold limit must be avoided for all operating conditions. The test for compliance with this requirement is usually operation at take-off and cruise conditions on the specified fluid at controlled lubricity conditions. The fluid lubricity level is checked periodically to ensure compliance is met. See Reference 6 for a detailed description of the test procedure.

End of Days Apocalypse

End of Days Apocalypse

This work on 2012 will attempt to note them allfrom the concepts andinvolvement by the authors of the Bible and its interpreters and theprophecies depicted in both the Hopi petroglyphs and the Mayan calendarto the prophetic uttering of such psychics, mediums, and prophets asNostradamus, Madame Blavatsky, Edgar Cayce, and Jean Dixon.

Get My Free Ebook


Post a comment