What are the characteristics of the design classifications of the components that make up an air filter?

make upAir FilterWhat are the characteristics of the design classification of the components of the

differentAir FilterAll of them have different design styles. Then we will give you a specific introduction about the body design of air filters, the design of air filter deflector plate, the design of air filter umbrella baffle plate, the design of air filter cartridge, water cup and protective cover, and the design of air filter drain valve. The following explains the design classification and key points of each part of the air filter:

I. Air filter body design

The body of the air filter is the matrix of the whole filter and the main bearing part, which largely determines the appearance and flow characteristics of the air filter. The material of the body is usually die-casting aluminum alloy or zinc alloy, and the plastic material is cheap but not high strength.

In the design, the air filter body appearance should be similar to the appearance of the pressure reducing valve and oil mist, and should be considered comprehensively. Appearance design is very important, it is related to whether it can be in the many manufacturers of triple products to highlight their products and open up sales. The author in the design process, the appearance of the design accounts for about 40% workload, which is a difficult point. The general principle of appearance design is: under the premise of ensuring the internal structure, the appearance of distinctive, simple, compact size, easy to disassemble and assemble the combination and modular design, especially consider how to facilitate the connection with other components.

In the current products, there are mainly 2 types of connection, one for the body has a beveled surface, by the fixed parts on the beveled surface tension fixed; the other by the bolt connection. The former is easy to disassemble and repair, the latter is compact size. At the same time, in order to ensure that the filter will not be installed in reverse, the valve body should have a conspicuous sign of the direction of gas flow.

The design of the interior of the air filter body is mainly the design of the flow path, because the flow path is one of the main factors affecting the flow characteristics. The flow path design should pay attention to

(1) To maximize the inlet area of the inlet runner, to ensure that the inlet runner area for the design of the caliber area of 1.5 to 2 times.

(2) The runner should be as short as possible, under the premise of meeting the strength, try to move the deflector plate up close to the air inlet, the short runner can also shorten the structure size.

Second, the air filter deflector design

The deflector plate of the air filter is a key component that affects the efficiency of water separation, and the blades of the deflector plate should pay attention to 4 points when designing:

(1) The blades should have sufficient strength and at the same time sufficient overflow area.

(2) the angle of the appropriate size, the angle is too large, the airflow cyclone is not obvious, the effect of water separation is not good; angle is too small, separated from the water will run upward, it is difficult to flow to the bottom of the water cup, blade to 30 ° ~ 45 ° is more appropriate.

(3) Rotation, many manufacturers use left rotation, but after testing, there is no significant difference between left and right rotation.

(4) The installation of the deflector must be firm and reliable, because the airflow has a large reaction force on the blades when passing through the deflector, which can easily make the deflector loose or fail.

III. Umbrella baffle design for air filters

The umbrella baffle is used to prevent the water at the bottom of the cup from being sucked back by the airflow and is designed with 3 points in mind:

(1) Umbrella-shaped water stopper umbrella plate part to have air pressure balance hole, the diameter of 1 ~ 2mm, for balancing the air pressure of the upper and lower 2 parts of the water cup.

(2) The part of the umbrella baffle in contact with the cartridge should have a certain degree of elasticity and strength to ensure that the cartridge and umbrella baffle will not come loose after assembly. Umbrella baffle material is generally used ABS or POM, so we should give full consideration to the aging of the plastic in the use of the process, to prevent the use of a period of time after the loss of elasticity, if necessary, you can add a lock nut.

(3) The umbrella plate part of the umbrella-shaped water stopper should be as large as possible, and the gap with the water cup is between 1 and 4mm, leaving a gap to facilitate the flow of separated water to the bottom of the cup.

IV. Design of air filter cartridges, water cups and protective covers

According to the need for filtration precision, different filter elements can be used, and there are 3 types of filter elements: metal mesh type, sintered type and fiber coalescing type. The metal mesh type has low filtration precision and the fiber coalescing type has high filtration precision. Commonly used sintered type and copper bead sintering, resin sintering and ceramic sintering 3 types, of which copper bead sintering is common. Different filtration precision can be achieved by choosing different diameters of copper beads. Generally, there are 4 kinds of filtration precision: 5μm, 20μm, 50μm, 100μm. The advantage of copper bead cartridge is that it can be cleaned and used many times.

The water cup of the air filter is usually made of transparent polycarbonate (PC) material, which makes it easy to observe the water level in the cup. The thickness of the water cup should be greater than 3mm, the higher the pressure the thicker the thickness used. Due to the fragile PC, generally used in larger sizes of the filter, to add a metal protective cover. When adding the protective cover, the protective cover should hold the bottom of the water cup, so that the protective cover can withstand the main pressure. Metal water cups can be used at high pressure, but with a transparent scale showing the water level.

V. Air filter drain valve design

(1) Simple manual drain valve. This simple, need to open the valve by hand when the drainage of water, after the drainage of water to close the valve. Commonly used are knob type small ball valve, button type thimble valve and so on. This type of valve design is simple, as long as the sealing problem can be solved. Manual valves must be operated manually, and the water level must be checked regularly and drained in a timely manner. If the water is not drained in time, it will cause secondary pollution and will not work as a water filter. This kind of valve has low cost, drains quickly and does not affect normal work, but the cost of manual maintenance is high.

(2) Spring-loaded automatic drain. When there is no air pressure or very low air pressure, the spring lifts the spool to drain. When there is air pressure, the spool is pressed to the O-ring seal, stop the drainage. This valve drainage requirements must stop the gas, can only be used in some of the places that can be frequently stop the gas, the advantage is that no manual control, low manufacturing costs.

(3) Automatic drain. There are 2 types of normally open and normally closed type, when there is no air pressure, the drain is in the open state, for the normally open type; the drain is in the closed state for the normally closed type. When the reset spring is installed in the outer 8 position, for the normally closed type; when the reset spring is installed in the piston inside the 9 position for the normally open type. Because of the similar structure, only the normally open type is introduced here. When there is no air pressure in the water cup, the float 11 falls by its own weight and closes the upper throttle port 3 with the sealing plug 12 through the control lever 1. The piston 4 moves down under the action of the reset spring 9, the piston rod is disengaged from the sealing channel, and the water and oil are discharged. When the air pressure in the water cup is greater than the low action pressure, the piston overcomes the spring force and friction to move upward, and the drain port is closed. When the water level in the water cup rises to a certain position, the buoyancy of the float is greater than the sealing pressure of the upper throttle port, the sealing plug is opened by the control rod, the air pressure enters the upper chamber inside the piston from the upper throttle port, the piston moves down and the drain port opens to drain. When the water level drops, the float closes the upper throttle port. Piston upper cavity gas pressure through the lower throttle hole discharge, due to the lower throttle port than the upper throttle port is small, the piston internal cavity of the gas can not be immediately drained, the piston moves up to close the drain port there is a certain delay, when the drain port is completely closed, the cup of water has been basically discharged. Automatic drainer of the single storage of water is relatively small, drainage than manual drainage frequently.