First of all, the function of each air compressor accessories on the main air source path in the air process is briefly explained:

1. Oil and gas barrels

The oil and gas barrel has two functions of oil and gas separation and oil storage. The compressed oil and gas mixture is discharged to the oil and gas barrel, and most of the lubricating oil can be separated by rotating in the oil and gas barrel; there is more lubricating oil in the oil and gas barrel, so that the hot oil that has just been separated will not immediately participate in the next cycle, which is conducive to reducing the discharge of oil. air temperature. There is an oil level indicator on the side of the oil and gas drum. There is a refueling hole on the barrel for refueling, and the oil level of the static lubricating oil should be between the upper and lower limits of the oil level gauge. The oil (water) ball valve is installed under the oil and gas barrel. The ball valve should be slightly opened before each operation to remove the condensed water in the oil and gas barrel (because water is heavier than oil, it is deposited in the lower part). As soon as oil comes out, shut it off quickly. Due to the wide cross-sectional area of ​​the oil and gas barrel, the flow rate of the compressed air can be reduced, which is conducive to the separation of oil droplets and plays the role of preliminary oil removal.

2. Air filter

The air filter is a dry type paper filter, and the pore size of the filter paper is about 5μm. Its main function is to filter out dust in the air and avoid premature wear of the screw rotor and premature blockage of the oil filter and fine oil separator. Usually every 500 hours of operation, the dust on its surface should be removed. The method of removal is to use low-pressure air to blow the dust from the inside out.

3. Oil and gas separator

The oil and gas separator filter element is made of multi-layer fine special fibers. The mist lubricating oil contained in the compressed air can be almost completely filtered out after passing through the oil fine separator. The oil particle size can be controlled below 0.1μm, and the oil content is Can be less than 3PPM.

4. Intake valve

The intake valve is a disc-type intake valve, which mainly controls the empty and heavy load through the opening and closing of the disc in the intake valve; there are two control methods, one is switch type, when the pressure reaches the high limit set value , close the air inlet, the pressure drops to the lower limit set value, and reopen the air inlet to work at full load. Another kind of capacity adjustment control, the disc of the intake valve is slightly closed with the proportional valve for capacity adjustment control, adapting to the external air consumption, so that the pressure is stabilized within a certain range, and the pressure does not reach the capacity adjustment pressure, the disc of the intake valve is fully open, the compressor is running at full load.

5. Safety valve

When the gas pressure in the oil and gas barrel is 1.1 times higher than the rated exhaust pressure, the safety valve will automatically jump up and release the pressure, so that the pressure drops below the rated exhaust pressure.

The way to check the safety valve is to lightly pull the deflation lever on the safety valve when the compressor is working at full load. If the safety valve can exhaust air, it is considered normal.

6. After cooler

The compressed air flowing out from the minimum pressure valve is passed to the aftercooler. The after-cooler and the oil cooler are made into one body, and their structure is the same, both of which are plate-up type. A cooling fan draws in cool air and blows it over the rear cooler rocker. The temperature of the compressed air after cooling is generally below the ambient temperature +15°C.

7. Minimum pressure valve

Located at the outlet of the fine oil separator above the oil and gas poke, the opening pressure is set to about 0.45MPa. The minimum pressure valve mainly has the following functions:

1. After the gas pressure of the oil and gas barrel exceeds 0.4MPa, it will be opened, which can reduce the air flow rate flowing through the oil fine separator, in addition to ensuring the oil fine separation effect, it can also protect the oil fine separator from being affected by too large pressure difference. damage.

2. When starting, the circulating pressure required by the lubricating oil is first established to ensure the lubrication of the machine.

3. Return function: when the pressure in the oil and gas barrel drops after shutdown, it prevents the backflow of compressed air in the pipeline.

The air flow of the air compressor:

Generally speaking, in the air process of the screw air compressor, after the air is filtered by the air filter to remove the dust, it enters the main compression chamber through the intake valve to be compressed and mixed with the lubricating oil. After the compressed air mixed with oil is discharged to the oil and gas drum, it is sent to the use system after passing through the oil fine separator, pressure maintenance valve and after-cooler.