There are six wearing parts of screw air compressor: air filter, oil filter, oil separator, lubricating oil, belt, and solenoid valve; do you know all these things?
1. Air filter
The air compressor air filter is composed of an air filter assembly and a filter element. The outside is connected to the air inlet valve of the air compressor through joints and threaded pipes, thereby filtering dust, particles and other impurities entering the air. Different air compressor models can choose the air filter to be installed according to the size of the air inlet volume.
Symptoms of failure: A clogged air filter will cause the air compressor to lose energy, waste electricity, and be easily penetrated by dust. Excessive dust entering the interior of the air compressor will affect the service life of the air compressor oil and cause the oil-gas separator to become clogged.
Troubleshooting: 1. The filter element is the core component of the filter. It is made of special materials. It is a wearing part and requires special care and maintenance.
2. After the filter has been working for a long time, the filter element has blocked certain impurities, which will cause the pressure to increase and the flow rate to decrease. At this time, it needs to be cleaned in time. 3. When cleaning, be careful not to deform or damage the filter element. The filter paper in the equipment is also one of the keys. The filter paper in the filter equipment is usually made of microfiber paper filled with synthetic resin, which can effectively filter impurities and has strong dirt storage capacity. The equipment also has great requirements for the strength of the filter paper. Due to the large air flow, the strength of the filter paper can withstand the strong air flow, ensuring filtration efficiency and extending the service life of the equipment. The pore size of the filter paper is about 10um. It should usually be removed every 1000 hours to clear the dust on the surface. The cleaning method is to use low-pressure air to blow the dust out from the inside out. The air filter is equipped with a pressure difference detector. If the display panel shows that the air filter is clogged, it means that the air filter needs to be cleaned or replaced.
2. Oil filter
The oil filter is generally a paper filter. Its function is to remove impurities in the oil such as metal particles, oil degradation products, etc. The filtration accuracy is between 5um-10um and has a protective effect on the bearings and rotors.
Fault symptoms: Oil filter failure Troubleshooting: Whether the oil filter should be replaced can be judged by its pressure difference indicator. If the pressure difference indicator light is on, it means that the oil filter is clogged and needs to be replaced. The oil and oil filter of a new machine need to be replaced after 500 hours of operation, and then replaced according to the pressure difference indicator light. If the pressure difference of the oil filter is large and the oil filter is not replaced, it may lead to insufficient oil intake, and the high temperature of the exhaust gas will cause the machine to trip. At the same time, the insufficient oil amount will affect the bearing life.
The effective use time of the oil filter is determined by two factors: 1. The amount of impurities. When the oil filter's ability to adsorb impurities reaches the upper limit, the effective service life of the oil filter has expired;
2. Machine temperature and filter paper’s carbonization resistance. The service life of the oil filter is different when the machine is at high temperature and at normal temperature. High-temperature models will greatly accelerate the carbonization of the filter paper and shorten the effective use time of the filter paper. In addition, the effective use time of poor filter paper will be very short. Use it under normal conditions and the quality is good. The effective filtration time of the oil filter is about 2000-2500 hours. When the variable frequency screw machine is used at low frequency for a long time, the temperature is usually lower, and there is more moisture in the oil barrel, so the filter paper has a higher waterproofing ability. When the variable frequency screw machine is used at low frequency, the pressure in the oil system will be low, and the oil filter needs to have low resistance and breathability. Good sex. Many people may think that oil filtering relies on filtration. The higher the precision, the better the filtration effect. At the same time, they worry that if the filtration precision is too high, the oil filter will be easily clogged. However, some studies believe that this is actually a misunderstanding. There is some relationship between the filtration accuracy of the oil filter and the filtration effect, but it is not the filtration accuracy that determines the filtration effect, but the adsorption capacity of the oil filter paper. The larger the dust holding capacity, the stronger the adsorption force and the better the filtration effect. Fiber filter paper has a good filtration effect because it has a large dust holding capacity, strong adsorption capacity, and strong carbonization resistance. However, the price of fiber filter paper is very expensive, and the filter paper factory does not sell it retailly. It needs to be customized in large quantities. If the oil filter does not have a particularly large sales volume, it is difficult to customize fiber filter paper. This is the main reason why few people use fiber filter paper. reason.
3. Oil separation core
The oil and gas separator filter element is made of multiple layers of fine glass fibers. The mist oil and gas contained in the compressed air can be almost completely filtered out after passing through the oil and gas separator. Under normal operation, the oil and fine separator can be used for about 3,000 hours.
The oil-water separation filter element is mainly designed for oil-water separation. It contains two types of filter elements, namely: coalescing filter element and separation filter element. Poor separation efficiency results in large oil consumption and heavy oil content in compressed air, which affects the operation of back-end purification equipment and the gas equipment cannot work properly; the pressure resistance increases after blockage, resulting in an increase in the actual exhaust pressure of the unit and an increase in energy consumption of the unit. ; After failure, the glass fiber filter separation material falls off and enters the oil, resulting in shortened life of the oil filter element and abnormal wear of the main engine; after the oil separator element is damaged, the oil directly escapes, resulting in large oil consumption, and also leads to high temperature of the unit due to lack of oil, which is serious. It may cause the machine nose to lock up.
Fault symptoms: clogging/damage/burnt/poor separation effect. Troubleshooting: The quality of the lubricating oil and the pollution degree of the surrounding environment have a great impact on its life. If the environmental pollution is very serious, consider installing a pre-air filter.
1. Clogging: When the oil separator core is clogged, it will cause excessive current in the air compressor motor. It is also possible that the oil separator core will be deformed due to excessive pressure, or the main engine will lock up when the motor is overloaded seriously. In addition, excessive current will shorten the life of the contactor or cause the contacts to burn and cause major accidents. Generally, screw air compressors will have a pressure gauge in front of the filter element. When the pressure difference between the pressure gauge in front of the filter element and the air supply pressure gauge reaches 0.08MPa, the oil separator element must be replaced.
2. Damage. When the oil separator core is damaged, you will find that the air compressor consumes very serious oil, and there will be a large amount of oil in the gas tank and pipelines. In serious cases, the air compressor oil will be discharged directly when the air tank drain valve is discharged. The main reasons for this failure are: (1) Failure to replace the oil separator core on time; (2) Selecting a poor quality oil separator core; (3) Failure to follow the procedures during the installation process, such as removing the oil separator core when installing the oil return pipe Penetration etc.
3． burn. The burning of the oil separator core is not common during the operation of the air compressor, but it does happen occasionally. The main manifestation is that the filter screen of the oil separator core is partially or completely carbonized, and even the metal shell of the oil separator core is burned. The main reasons for such failures are: (1) The quality of the air compressor oil is poor; (2) The quality of the oil separator core itself is too poor; (3) When installing the oil separator core, there is no reliable connection between the oil separator core shell and the oil separator barrel and cannot be grounded. , when there is static electricity, the oil mist will be ignited and the oil separator core will be burned.
4. The separation effect is poor. The main manifestation is that the compressed air contains too much oil, causing damage to post-processing equipment and user equipment. The main reasons for this failure are: (1) The quality of the oil separator core itself is too poor; (2) The installation was not performed according to the regulations.
4. Lubricating oil
The function of air compressor oil is to form a protective film between the critical points of the two friction screws to avoid contact between the screws, thereby buffering the friction, lubrication, and reducing wear; in addition, it can cool down, reduce noise, Sealing, anti-rust and other functions.
Fault symptoms: Lubricating oil failure Troubleshooting: Indeed, whether the new air compressor needs to replace the lubricating oil after 500 hours of operation or every 4,000 hours in the future, this is all based on the standard environment, and in the screw type In the actual use of air compressors, many factors will affect the performance of lubricating oil. Because of this, we need to determine the replacement cycle according to the specific use environment.
So what factors will affect the replacement cycle of screw air compressor lubricant? At present, the main points that everyone agrees on are:
1. Quality of lubricating oil: The quality of lubricating oil will directly determine its service life. As long as the lubricating oil is produced by regular manufacturers and has qualified quality verification, it can be replaced every 4,000 hours under standard conditions, while the replacement cycle of inferior lubricating oil is very short;
2. Humidity of the air: The greater the humidity in the air, the more moisture will enter the inside of the air compressor, and the mixture of moisture and lubricating oil will cause the lubricating oil to deteriorate, which will affect its service life;
3. Impurities: including impurities that enter with the air and impurities produced by friction inside the air compressor, etc. Impurities can contaminate the lubricant, causing it to fail;
4. Acidic and alkaline gases: There are a large amount of acidic and alkaline gases in the use environment of some air compressors. Their types of gases will also affect the working performance of the lubricating oil, thus shortening its service life.
5. Belt
The belt has good elasticity, which can alleviate impact and vibration during work, and the movement is smooth and noiseless. When the load is too large, the belt slips on the pulley, thus preventing other parts from being damaged and playing a protective role.
Fault symptoms: The belt elasticity is not good. Troubleshooting: After turning off the air compressor, and after the temperature inside the standby body drops and there is no pressure, check the current status of the transmission belt. Due to the particularity of the screw air compressor's structure, how to replace and adjust it depends on its tightness. If there are no serious problems such as deformation, you only need to select the bolts accordingly to make them meet the required conditions. However, when it is damaged beyond repair, it must be replaced with new parts.
The caveats are to keep the tension consistent throughout the belt and to be prepared to prevent slipping. After installation, test run for about thirty hours and observe the changes. In fact, the key here is strength. Mastering this strength can avoid accidents such as disconnection.
If the screw air compressor drive belt replacement and adjustment can be done well, it will also benefit the work of the motor and other accessories, which will virtually reduce the load. After completing all the steps, fix the machine head. Carry out in an orderly manner, be rigorous in implementation, and avoid errors. In many cases, damage occurs due to operational errors. Maintain sufficient vigilance, make sufficient preparations, and make timely adjustments to each data.
6. Solenoid valve
Fault Symptom: No Action Troubleshooting: Failure of the solenoid valve on the screw air compressor will directly affect the action of the switching valve and regulating valve. Common solenoid valves that do not work should be checked from the following aspects:
1. The screw air compressor solenoid valve connector is loose or the wire ends are dropped, and the solenoid valve cannot be powered. The problem can be solved by tightening the wire ends.
2. The solenoid valve coil of the screw air compressor is burned out. If the solenoid valve coil is burned out, you can remove the wiring of the solenoid valve and measure it with a multimeter. If it is open circuit, the solenoid valve coil is burned out. The reason is that the coil is damp, resulting in poor insulation and magnetic flux leakage, causing excessive current in the coil and burning. Therefore, rainwater must be prevented from entering the solenoid valve. In addition, if the spring is too strong, the reaction force is too large, the number of coil turns is too few, and the suction force is insufficient, the coil may also be burned. During emergency handling, the manual button on the coil can be moved from the "0" position during normal operation to the "1" position to open the valve.
3. The solenoid valve of the screw air compressor is stuck. The cooperation gap between the slide valve sleeve and the valve core of the solenoid valve is very small (less than 0.008m). They are usually installed in a single piece. When mechanical impurities are brought in or there is too little lubricating oil, it is easy to get stuck.
Solution: Use a steel wire to poke it through the small hole in the head to make it bounce back. The solution is to remove the solenoid valve, take out the valve core and valve core sleeve, and clean it with CCI4 to make the valve core move sensitively in the valve sleeve. When disassembling, pay attention to the installation order of each component and the location of external wiring so that reinstallation and wiring are correct. Also check whether the oil spray hole of the lubricator is blocked and whether the lubricating oil is sufficient.
4. The solenoid valve of the screw air compressor is leaking. Air leakage will cause insufficient air pressure, making it difficult to open and close the valve. The reason is that the sealing gasket is damaged or the slide valve is worn, causing air blow-by in several cavities.
When checking for a solenoid valve failure, you should wait until the solenoid valve loses power to deal with it. Directly replace the solenoid valve to remove the burnt coil, or repair the leakage of the valve body.