Fuel system inhibiting, Other Engineering

Fuel system inhibiting.

The fuel used in turbine engines usually contains a small quantity of water which, if left in the system, could cause corrosion. All the fuel should therefore be removed and replaced with an approved inhibiting oil by one of the following methods:

Motoring Method

This should be used on all installed engines where it is convenient to turn the engine using the normal starting system. A header tank is used to supply inhibiting oil through a suitable pipe to the engine. A filter and an on/off cock are incorporated in the supply pipe, which should be connected to the low pressure inlet to the engine fuel system and the aircraft LP cock closed. After draining the engine fuel filter a motoring run should be carried out bleeding the high pressure pump and fuel control unit, and operating the HP cock several times while the engine is turning. Neat inhibiting oil will eventually be discharged through the fuel system and combustion chamber drains. When the motoring run is complete the bleeds should be locked, the oil supply pipe disconnected and all apertures sealed or blanked off.

Pressure Rig Method 

This may be used on an engine which is installed either in the aircraft or in an engine stand. A special rig is used which circulates inhibiting oil through the engine fuel system at high pressure. The fuel filter should be drained and, where appropriate, the aircraft LP cock closed. The inlet and outlet pipes from the rig should be connected to the high pressure fuel pump pressure tapping and the system low pressure inlet respectively, and the rig pump turned on. While oil is flowing through the system the components should be bled and the HP cock operated several times. When neat inhibiting oil flows from the combustion chamber drains the rig should be switched off and disconnected, the bleed valves locked and all apertures sealed or blanked off.

Gravity Method 

This is used when the engine cannot be turned. A header tank similar to the one used in the motoring method is required but in this case the feed pipe is provided with the fittings necessary for connection at several positions in the engine fuel system. The fuel filter should first be drained then the oil supply pipe connected to each of the following positions in turn, inhibiting oil being allowed to flow through the adjacent pipes and components until all fuel is expelled:

(a) High pressure fuel pump pressure tapping.
(b) Fuel control unit pressure tapping.
(c) Burner Manifold.
(d) Low pressure inlet pipe.

Components should be bled at the appropriate time and the HP cock operated several times when inhibiting the fuel control unit. All bleeds and apertures should be secured when the system is full of inhibiting oil.

 

Posted Date: 9/12/2012 9:20:13 AM | Location : United States







Related Discussions:- Fuel system inhibiting, Assignment Help, Ask Question on Fuel system inhibiting, Get Answer, Expert's Help, Fuel system inhibiting Discussions

Write discussion on Fuel system inhibiting
Your posts are moderated
Related Questions
The following is the capital structure of X Ltd. as on 31st Dec 2003 Rs in m

Duct With Flow Control-Aircraft maintenance: BERNOULLI'S THEOREM This theorem can be related to the relationship between pressure and velocity existing in the air flowing

i am doing be in mechanical engg in india. so can i do my masters in geoophysic ?

Compressor stall and surge: ‘Surge' can occur in both centrifugal and axial flow compressors and is the reversal of the airflow in the compressor. It is a very undesirable con

Fire safety log book: The occupier's fire safety log book should be checked during an inspection to see that the system is being tested regularly and serviced and maintained a

Seekers   There are two main types of sensor used in autonomous vehicles (seekers and position/attitude sensors) - although not all systems have both.            - Airc

the true length of a line is known to be 500m.the line was again measured with a 20m tape and found to be 502m,what is the correct length of the 20m tape.

Function setxor and set function unique: The function setxor receives two vectors as input arguments, and returns a vector having all the values from the two vectors which are

Latches and flip-flop circuits: Latches and Flip-flop circuits are a combination of logic gates that perform basic memory functions for computers and peripherals. Both these c

identify the types of borrowers who have access to funds through the issue of debentures