Generally, the oil content of the compressed air of the oil-injected screw air compressor is no more than 3ppm. When the oil content of the compressed air exceeds this standard, we usually call it high fuel consumption, commonly known as running oil or flying oil. Air compressor oil running is a headache problem that has plagued manufacturers, distributors and users for a long time, and it is also one of the most common failure phenomena. So how to determine whether the machine is high in fuel consumption? The analysis is mainly from the following aspects:

1. Whether the oil level of the machine has dropped significantly. Observe the oil level indicator line, it is best to compare the machine under the same environment and pressure after the machine is turned on and stably loaded. For example, if the pressure is also loaded to 7 kg, whether the oil level changes significantly before and after the time. It should be emphasized here that after the machine is turned on and running stably, pay attention to conditions such as temperature and pressure, otherwise it may cause inaccurate oil level observation and cause misjudgment. For example, a small number of people observe the oil level in the shutdown state, and if they can’t see the oil, they will reflect The machine is running out of oil, and this judgment standard needs to be improved.

2. Whether there is oil leakage in the oil system of the machine, such as oil pipe aging, oil leakage in the machine head, oil leakage in the cooler, etc., the best way is to open the door of the machine and look at the bottom of the machine with a flashlight to see if there is any Pieces of motor oil.

3. For machines with a trap, take a sample from the drain outlet of the trap, drain the water and place it in a clean container (a clean mineral water bottle is recommended) and let it settle for about five minutes, and observe whether it is a bit or oily oil Gather on the surface of the container. Before precipitation, most of the water sampled will be milky white, and there are only a few thin colorful oily flowers when observed against the light.

4. For machines without a water separator, you can observe the drainage condition of the gas storage tank. Compare with the previous normal situation, whether the discharged water brings out too much oil. A small amount of oil is a normal phenomenon.

Through the above aspects, we can basically determine whether the machine has a problem of high fuel consumption. In the actual production process, we found that most of the high fuel consumption failures are not caused by the quality of the oil. It is concluded that the following five major factors are responsible for the high fuel consumption of the machine

(1). The primary separation effect of oil barrels is not good

The main problems are the unreasonable size design of the oil separator, the unmatched diameter or angle of the air inlet of the oil separator, and the defect of the baffle (such as trachoma, desoldering), etc.:

1. The unreasonable size design of the oil separator barrel, and the mismatch of the diameter or angle of the air inlet of the oil separator barrel is mainly a new machine.

2. The defect of the baffle is mainly the old machine. After many years of use, the air compressor will inevitably have some failures, and the defects caused by the baffle are no exception.

(2). Problems with oil return system

The criterion for judging whether the oil return effect of the machine is good or not is the oil storage at the bottom of the oil distribution center, the less the better, and it is better to have less than one fingernail shell.

Problem performance: 1. The oil return check valve has foreign matter that is not smooth or completely blocked; 2. The gap between the oblique port oil return pipe and the bottom of the oil separator is too large or the oil return pipe breaks the bottom of the oil separator when the oil return pipe is installed; 3. Insert the flat oil return pipe when installing The oil return port is blocked up to the bottom of the oil separator; 4. The oil return pipe is broken, etc.

The above-mentioned problems will cause the oil not to return to the nose in time, and the condensed oil will be taken up by the compressed air, and will be taken away along with the separated compressed air, causing the oil to run away.

Treatment suggestions: 1. Clean the oil return check valve or replace with a new oil return check valve; 2. Install the oblique port oil return pipe to the center of the bottom of the oil separator groove; 3. Polish the flat port oil return pipe into an oblique port and insert it into the oil separator recess The bottom of the tank; 4. Replace the oil return pipe with a new one. Failure to return the oil in time will cause the machine to run out of oil quickly, and in severe cases, it will cause the machine to stop at high temperature. Therefore, it is recommended that after-sales personnel perform machine maintenance.

Carefully clean the oil return check valve and oil return pipe and install them carefully. If there is too much oil at the bottom of the oil separator groove during maintenance, you must carefully check and clean the oil return system.

(3). User operating conditions

It mainly includes the use of drastically reduced pressure and long-term low-temperature operation of the machine.

1. Use for drastically reduced pressure. Due to the increase in air consumption in some factories, the exhaust pressure when using the machine is much lower than the rated pressure on the nameplate of the air compressor, especially for low-pressure machines. Pay more attention to this aspect, because the excessive pressure reduction of the low-pressure machine will be more obvious. . For example, a low-pressure machine with a rated pressure of 5 kg is generally maintained at 4.5 kg, but the actual air pressure is only about 4 kg (or even lower). In this way, the air compressor has been in a state of drastically reduced pressure for a long time, unable to reach a reasonable pressure range, the exhaust pressure is greatly reduced, the flow rate of the oil and gas mixture is too fast, and the machine runs out of oil beyond the oil treatment range. The air compressor is a highly professional and technical equipment, which should be made in the factory.

Reasonable use under the guidance of the engineer, for the inevitable drastic reduction of pressure, you can reduce fuel consumption by adding machines or custom-made special oil.

2. The machine runs at low temperature for a long time. Some machines run at low temperature for a long time, and the compressed water in the compressed air cannot evaporate in time and adhere to the oil filter material. If this happens, the structure of the oil filter material will be damaged and cause oil running.

(4). Other factors

For some models, such as the pressure difference sensor collusion, the minimum pressure valve is not tightly sealed or opened in advance, the oil leaks in the oil cooler, and the oil is damaged by external factors.

1. The pressure difference sensor is in collusion, and part of the oil and gas mixture before separation is directly removed without passing through the separation system, causing the machine to run out of oil.

2. If the minimum pressure valve is not tightly sealed or opened in advance, the machine will take longer to build up the internal pressure at the beginning of operation. At this time, the compressed air at low pressure will have a higher oil mist concentration, and the flow rate will be too fast, which will also cause the machine to run out of oil.

3. When the air compressor oil cooler leaks into the air cooler, the organic oil will directly enter the air cooler and accompany the compressed air to the air outlet, causing the machine to run out of oil.

4. The air compressor oil cooler leaks into the water cooler from the perforation. As the oil pressure is generally high, the water pressure is generally lower than 2-3kg/cm2. The oil enters the cooling water system through the perforation, causing the machine to run out of oil.

5. The oil separator is damaged and deformed due to some external reasons, which leads to high fuel consumption of the machine, such as installing the oil return pipe to penetrate the bottom of the oil separator.

The place where screw air compressor is easy to misunderstand in application:

1. Milky white condensed water does not indicate high oil content. Milky white is not oil dissolved in water, but compressed air dissolved in water. You can use a clean mineral water bottle to connect a part of condensed water to do a small experiment, and let it settle for a while , The milky white in the condensate

The color will disappear.

2. The oil content is initially installed, and the oil return volume of some models is seen on the oil return pipe oil sight glass of some models. This is not accurate, and it usually takes 2 to 6 hours for the oil content to reach the saturated state.

3. A hot oil return pipe does not mean that the oil return system is normal. If the oil return pipe is hot, the oil return pipe is cold. It can be basically concluded that the oil return effect of the machine is not good.

4. A small amount of oil traces can be seen after the gas storage tank is discharged. It is not sure that the fuel consumption is high. The original oil-injected screw compressor has a certain range of oil content. After the gas storage tank is stored and precipitated, it is normal for a small amount of oil .

5. Once the machine has high fuel consumption, it is recommended that the nearest dealer's after-sales personnel go to the site to check whether there is any oil leakage, shut down and open the minimum pressure valve to check the oil storage at the bottom of the oil separator to ensure that the oil return system is in good working condition.