Full-automatic backwash filter

Abstract

The invention relates to a full-automatic backwash filter. The full-automatic backwash filter comprises a tubular barrel and a lower barrel, wherein a tubular filter element is arranged in the barrel, and a cleaning rotating shaft is arranged in the filter element; the filter element is composed of a tubular inner mesh plate, a tubular outer mesh plate and a foldable filter screen; a left scraping plate and a right scraping plate are symmetrically arranged on the cleaning rotating shaft, wherein the left scraping plate is provided with a cleaning groove, the cleaning groove stretches deep into the left scraping plate in the radial direction of the cleaning rotating shaft to form a flow passage, and the cleaning groove is communicated with a tubular shaft at the lower end of the cleaning rotating shaft; an opening of the cleaning groove makes contact with the inner mesh plate of the filter element. According to the full-automatic backwash filter, the structural design of the fixed filter element and the cleaning rotating shaft is adopted, the running torque of the cleaning rotating shaft is quite small, the opening of the cleaning groove in the left scraping plate is an inverted horn-shaped opening, a divergent nozzle design in fluid dynamics is adopted, differential pressure inside and outside the filter element is fully utilized, so that the flow velocity of cleaning fluid is increased, and the cleaning effect is improved effectively; the service life of the filter element can be effectively prolonged, and the maintenance cost of the filter in a later period is lowered substantially.

Description

technical field [0001] The invention belongs to the technical field of precision fuel filter equipment, in particular to a fuel filter device for marine engines. Background technique [0002] At present, due to the consideration of economy, the use of inferior fuel oil (heavy oil) in marine engines has become an inevitable trend. With the trend of large-scale marine diesel engines, users have more and more requirements on the flow range, accuracy level and service life of fuel filters. At the same time, in order to ensure the continuity of ship operation, marine fuel filters generally adopt the design of automatic flushing. The automatic cleaning of fuel filters generally adopts two forms: isolation cleaning and continuous cleaning. The former method is used earlier, but in the actual cleaning process, there is a switching action of the isolation mechanism, which is likely to cause discontinuity of fuel supply. During the period, air is easily mixed into the fuel supply sys...

AI Technical Summary

Problems solved by technology

At present, for such continuous cleaning fuel automatic flushing filter, the filter element is rotated during the cleaning process. In order to ensure the rotation of the filter element, a filter element shaft and a support frame must be installed on the filter element structure. The complicated filter element structure will make production quite difficult; at the same time Due to the large-scale development trend of diesel engines, the requirements for the effective flow rate of the filter element are increasing, and the size of the filter element has to be increased accordingly. With the increase of the diameter of the filter element, the size of the support member needs to be increased to meet the structural strength requirements of the filter element. , but the increase of the support member will inevitably reduce the effective flux of the filter element. In order to increase the effective flow rate, the size of the filter element must be increased, resulting in a vicious circle in structural design; The increase of the sealing material has higher requirements, and at the same time, the running clearance of the filter element will be enlarged accordingly.

The temperature difference of different oil products of marine fuel oil is about 100°C, and the rotation clearance of the filter element is difficult to take into account the difference between the hot state and the cold state due to thermal expansion and contraction, which will cause easy oil leakage when the filter element enters and exits in the cold state, seriously affecting the filtering effect ;The increase in the size of the filter element will also increase the resistance of the filter element rotation, which directly affects the size of the filter element drive mechanism

To sum up, due to the limitation of the structure of the rotary filter element, the most widely used fuel filter for continuous cleaning at present generally has complex structure of the filter element, large component size, small effective flow rate of the filter element, and easy occurrence of oil spillage (clean oil and dirty oil cannot be effectively Isolation), large rotational torque, no thermal expansion compensation, and contact between the cleaning device and the cleaning point of the filter element to cause damage to the filter element, etc.

Images