enEN
BLOG

Always there for you

Q & A

Home > News > Q & A

Six causes of faults ‘The exhaust of the air compressor contains oil’

Time: 2020-11-25 09:56:03

Among compressor failures, the fault with exhaust oil is the most common. The main factors causing the fault with exhaust oil are:

1.The oil separation core is damaged

During the operation of the air compressor, if the oil separation core is damaged, such as breakage or perforation, it loses its function of oil and gas separation. That is to say, the mixed gas and the exhaust pipe of the compressor are directly connected, so a large amount of cooling oil is not separated, and it will be discharged out of the body along with the gas, causing an oil-carrying fault during the exhaust process.

1.The oil separation core is damaged

During the operation of the air compressor, if the oil separation core is damaged, such as breakage or perforation, it loses its function of oil and gas separation. That is to say, the mixed gas and the exhaust pipe of the compressor are directly connected, so a large amount of cooling oil is not separated, and it will be discharged out of the body along with the gas, causing an oil-carrying fault during the exhaust process.

2.The oil return line is faulty

In the working process of the screw air compressor, the oil return pipeline shoulders important responsibilities. The oil separation core and the compressor inlet will form a pressure difference. Under the action of this pressure difference, the oil return pipeline is responsible for removing the oil. The oil collected at the bottom of the separation core is transported back to the compressor for continued use during the next cycle. If the oil return path is blocked, broken, or installed incorrectly, the oil collected at the bottom of the oil separation core cannot be transported back to the compressor, resulting in excessive oil accumulation at the bottom, which is not transported back to the compressor. As the gas is exhausted, oil will appear during the exhaust process.

3.System pressure control is too low

During operation, if the system pressure is controlled too low, it will cause the centrifugal force in the separator to be less than the required centrifugal force of the work. Then the function of the separator will not be fully reflected, which will cause the gas entering the core of the separator in the next stage. The oil content is too high and exceeds its separation range, which leads to incomplete separation of oil and gas, and oil-carrying faults occur in the compressor exhaust process.

4.The minimum pressure valve fails

The function of the minimum pressure valve is to ensure that the system pressure is controlled above the minimum pressure during operation. If the minimum pressure valve fails, the minimum pressure of the system cannot be guaranteed. Because the air consumption of the air transport equipment is very large, the system pressure will be too low and the oil return line cannot return oil. The oil accumulated at the bottom of the oil separator core will not be able to return to the compressor, and will be discharged from the compressor with the compressed gas, causing oil-carrying failure during the flat exhaust process.

5.Excessive cooling oil added in the compressor

Before the compressor is running, too much cooling oil is added, which exceeds the range of the compressor. During the operation of the compressor, because the oil level is too high, although the separation system separates the oil and gas, in the gas discharge, The gas will also involve the cooling oil in the gas and discharge it, causing the oil content in the exhaust gas to be too high, causing an oil fault.

6.Unqualified cooling oil quality

Before the compressor is running, unqualified cooling oil is added, or the cooling oil exceeds the applicable time, and the cooling effect cannot be achieved. Then during the operation of the screw compressor, the cooling oil loses its function and cannot separate the oil and gas. Then there will be oil faults during the exhaust process.

Troubleshooting steps

When it is found that there is oil in the exhaust of the compressor, it is not necessary to blindly disassemble the equipment, but to analyze the above causes and follow the steps from easy to difficult to determine the location of the fault. This can reduce a lot of repair time and manpower.
When the compressor starts normally and the system reaches the rated pressure, slowly open the exhaust gate valve with the opening as small as possible to allow a small amount of gas to be discharged. At this time, use a piece of dry paper towel to face the exhaust airflow. If the paper towel changes color immediately and has oil droplets, it can be judged that the compressor's exhaust has excessive oil. According to the amount of oil in the exhaust gas and different time periods, the fault location can be correctly judged.
When the opening of the exhaust gate valve is increased, the exhaust airflow is found to be in an uninterrupted dense mist, indicating that the airflow contains a large amount of oil, and then check the oil return situation of the oil return pipe observation mirror. If the oil return of the oil return pipe observation mirror increases significantly, it is generally because the separator core is damaged or the separator's cooling oil has been added too much; if the oil return pipe observation mirror does not return oil, the return pipe is generally broken or blocked.
When the opening of the exhaust gate valve is increased, it is found that the front part of the exhaust airflow is in a dense mist shape, and it is normal after a period of time; continue to increase the opening of the exhaust gate valve, open all the exhaust valves, and then observe the system pressure gauge , If the display pressure of the pressure gauge is lower than the set pressure of the minimum pressure valve, the exhaust valve is still exhausting and the airflow is in an uninterrupted dense mist. When this phenomenon occurs, the fault is generally the failure of the minimum pressure valve.
After a normal shutdown, the automatic vent valve will exhaust. If there is a large amount of oil in the exhaust, the automatic vent valve is damaged.

Hot categories

whatsapp