Jet-Fuel Thermal Oxidation Tester

High temperature stability of the fuels was measured using an Alcor, Inc. Jet Fuel Thermal Oxidation Tester (JFTOT) (j ). Low temperature (storage) stability was determined by measurement of gums, contamination and peroxide concentration (all by ASTM standard methods) before and after exposure to temperatures of 60 C for four weeks. The fuels were stored in l low actinic, dark pyrex glass bottles and were loosely covered to prevent exposure to airborne particulates. Air could still diffuse into the vessel. The vessels with fuel and various additives were thermostated at 60 C for the specified length of time. 

Better correlation between test results and refinery experience with anti-foulants is claimed with data from the Jet-Fuel Thermal Oxidation Tester (JFTOT) developed by a San Antonio, Texas firm. The device operates on the same principles as the Erdco coker developed in 1965 by Amoco, and according to ASTM D-1660. One of the main advantages of the JFTOT tester is that it uses only one quart of fuel. 

This test method for measuring the high temperature stability of gas turbine fuels uses the Jet Fuel Thermal Oxidation Tester (JFTOT) that subjects the test fuel to conditions that can be related to those occurring in gas turbine engine fuel systems. The fuel is pumped at a fixed volumetric flow rate through a beater after which it enters a precision stainless steel filter where fuel d radation products may become trapped. 

Jet Fuel Thermal Oxidation Tester (JFTOT)—Five models of suitable equipment may be used as indicated in Table 1. 

A2.1.1 The instrument described in this annex is the Jet Fuel Thermal Oxidation Tester, or JFTOT, that is used to test the thermal oxidation stability of turbine fuel. There are five models of JFTOT which will be described. All provide a means to pump the sample once through the test system across the metal test coupon and through a test filter. There are means to control and measure coupon temperature, system pressure, and pressure drop across the filter, and methods of control and measurement vary with each model of JFTOT. Mechanism for pumping is positive displacement using a gear pump or piston pump. 

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