Fuel filter, an important device in the fuel supply system of diesel generator sets

We know that the working process of diesel generator fuel supply system is according to the working requirements of diesel engine, in a certain speed range, a certain amount of clean diesel fuel, in a certain time, with a certain pressure to atomize good diesel fuel sprayed into the cylinder according to a certain injection law, and make it and compressed air quickly and well mixed and combustion, and to have clean diesel fuel, the role of the fuel filter can not be ignore.

 

Various types of diesel fuel itself will contain a certain amount of impurities, such as dust, carbon residue and gum, diesel fuel transportation and storage process, may also be mixed with more dust and moisture, the longer the storage, due to oxidation and gum generated by the more, these impurities on the diesel generator set oil supply system precision coupling has a great danger, the moisture may also start parts rust, gum may make the precision coupling jammed Therefore, the fuel filter must be set in the fuel supply system to eliminate various mechanical impurities in the fuel and ensure the normal operation of the fuel supply system.

 

Fuel filter according to its filtering effect, can be divided into two categories of coarse filter and fine filter, general diesel generators will be these two filters in series in the fuel supply system.

 

(1) Fuel coarse filter. The coarse fuel filter is installed before the fine filter, only the larger mechanical impurities in the fuel (0.06~0.07mn or more) filter out: some diesel generators do not set up a separate coarse filter, but add a screen at the fuel tank outlet to play the role of coarse filter.

 

(2) fuel fine filter. The function of the fuel fine filter is to filter out the very fine impurities in the fuel to ensure that the fuel sent to the fuel system is not contaminated, the fine filter is generally made of felt, cotton thread, filter paper and other filter core.

 

The fuel filter is mainly composed of three parts: filter element, housing and filter seat, as shown in the figure for the 135 series diesel engine fuel filter assembly section, all models are common, except for the relief valve 8 has two structures, according to different models choose C0810A or C0810B filter.

 

The fuel is sent to the fuel filter by the fuel pump, and the impurities in the fuel are removed by the paper filter element and then fed into the inner cavity of the filter cylinder, and then passed to the injection pump through the oil collection chamber on the filter seat. The filter seat is equipped with an oil return joint and a relief valve inside, when the fuel pressure in the fuel filter exceeds 78kPa (0.8kgf/cm2), the excess fuel is returned to the fuel tank by the oil return joint. Connecting low pressure fuel line should be according to the arrow on the seat, not connected to the wrong side, the bottom of the filter element sealing washer installed in the spring seat, the spring will seal the seal washer tightly in the bottom of the nut to play a sealing role, the filter seat and the shell connected by a tie rod, and a rubber ring seal, the upper end of the filter seat has a bleed screw plug, in use can loosen the bleed screw plug to clear the air in the fuel filter.