A Filter Regulator is used to control the speed and precision of the flow of liquids and air, whereas the filter cleans the air that travels from the compressor. What happens is the airline filter scrubs, strains and traps solid particles (dust, dirt, rust) and separates liquids (water, oil) within the compressed air.
Filters are installed in the air line upstream of regulators, lubricators, directional control valves, and air driven devices such as cylinders and air motors.
The classification is mainly classified; the filter is divided into three types: gravity filter, vacuum filter and pressure filter according to the different methods of obtaining the driving force of filtration.
The pressure formed on the filter medium with the aid of the gravity and the position difference of the suspension is used as the driving force for the filtration, which is generally intermittent operation, such as a sander.
A negative pressure is formed at the outlet of the filtrate as the driving force for filtration. The operating vacuum pressure of the industrial vacuum filter is (2.5～8.0)×105 Pa. The temperature of the suspension during filtration should be lower than the vaporization temperature of the filtrate under the operating vacuum. This filter is divided into batch operation and continuous operation. The intermittently operated vacuum filter can filter suspensions of various concentrations. The vacuum filter is filled with suspension in the container shell. The filter leaf wrapped with filter cloth on both sides is immersed in the suspension, and the inner cavity of the filter leaf is connected with the vacuum system. After the filtrate is sucked out, it is led out by the pipe, and the filter residue accumulated on the surface of the filter leaf is removed after the shutdown. Continuously operated vacuum filters are suitable for filtering thick suspensions containing more solid particles. The working principles of the rotary drum vacuum filter, the inner filter surface rotary drum vacuum filter, the disc vacuum filter and the tipping bucket vacuum filter are similar. The entire filter surface is divided into a plurality of separated filter chambers, and each rotating filter chamber is sequentially connected to each fixed pipe through a distribution valve to suck out the filtrate and lotion in the filter chamber, or send compressed air. Each filter chamber rotates one circle to complete the whole process of filtering operation, and the operations of multiple filter chambers are connected to form continuous filtration. The structure of the belt vacuum filter is similar to that of the belt conveyor, with a continuous filter belt suitable for easy-to-filter suspensions. The belt vacuum filter, the inner filter surface drum vacuum filter and the tipping bucket vacuum filter are all fed on the top of the filter medium (filter cloth), which is especially suitable for the suspension of solid particles with high density and fast sedimentation.
It uses the pressure applied at the inlet of the suspension or the mechanical squeezing force applied to the wet material as the filtering driving force. It is suitable for suspensions that require a large filtering pressure difference. It is also divided into two types: intermittent operation and continuous operation. Intermittently operated tube-and-tube filter and pressure filter are used for low-concentration suspension filtration. The filter is also a kind of intermittently operated pressure filter, which is divided into three types: plate and frame type, box type and vertical type, and has a wide range of uses. The oil filter is a plate and frame filter press unit equipped with accessories such as an oil pump and a vacuum evaporator. Continuously operated rotary drum pressure filter and disc pressure filter perform pressure filtration in a closed shell, and their structure is similar to rotary drum vacuum filter and disc vacuum filter. Due to the complex structure, there are fewer applications.
Commonly used pressure filtration is to use a smaller filter chamber volume or apply mechanical squeezing force to filter. The filter residue has a low moisture content and is suitable for suspensions with a high concentration of solid particles. In the belt squeeze filter, the wet filter residue, which has been initially deliquored by gravity or vacuum, moves between two filter belts, and is then squeezed and deliquored by rollers. The screw press filter has a cylinder with pores, in which there is a rotating spiral, the depth of the spiral groove is different, the material is added from the deep groove end to the shallow groove end, the space of the filter chamber is gradually reduced, the material is squeezed, and the filtrate flows from the cylinder The pores are discharged and the filter residue is discharged from the small end.