Aircraft and Aircraft Engine Fuel Pump Low Lubricity Fluid Endurance Test
This procedure is intended to apply to fuel pumps. This procedure will be defined in terms of recommended test fluid, test setup, test conditions, and test method. This procedure may be used for other fuel system components, by testing in conjunction with the pump, which normally supplies the component inlet flow, or a substitute test pump of similar capacity. This procedure may be used, with variations in test conditions and test fluid for performing pump evaluation tests. Tests at progressively increasing pump speeds and pressures will provide design limitation data. Alternate test periods on a test pump and another pump, of a design for which actual service durability is known, will provide useful comparison data.
Rationale: Section 3.4: 1. "Pump speed, engine flow, and discharge pressure shall be maintained at the conditions required for engine maximum normal steady-state loading condition for the duration of the test."
A statement should be added to allow for deviation from stated conditions if supplier or purchasing authority wish to conduct test at differing conditions.
Section 3.4: 6. "Fluid temperature at pump inlet (T2): 38 to 41 °C (100 to 106 °F) or that determined by the gear stage inlet temperature of the performance specification for the conditions specified in 1."
It would be easier for users to interpret the requirement if there were a criteria to decide which of the "38 to 41" or "the gear stage inlet temperature of the performance specification for the conditions specified in 1" to use.
Section 4.3.4 "building with lube" and Section 4.1.2 "packing lubricants"
It is recommended that assembly lube be limited as it inhibits the ability to dry the fuel.
A.1 Paragraph 14:
Remove plastic center support from clay filter bags
2500 pph max flow per bag
Latex or Neopreen instead of cotton gloves