At present, it has entered late December, and many areas in the north have been exposed to icy conditions for a long time, and the outdoor temperature has been below 0°C for a long time. How to ensure that the air compressor operates stably in cold weather is worthy of attention. Today, the editor will teach you how to make the air compressor survive the winter smoothly. The winter maintenance of the air compressor is worth learning.
Winter maintenance
The biggest obstacle to air compressor operation in winter is low temperature. Low temperature will cause the viscosity of lubricating oil to increase. Once the air compressor is stopped, it will be difficult to start for a period of time. We can avoid this problem by ensuring the temperature of the air compressor room. At the same time, the circulating water flow rate should be modified to 1/3 of the original. This can reduce the cooling effect of the cooler and ensure that the lubricating oil temperature is not too low. In addition, before starting the air compressor every morning, we can rotate the pulley 4-5 times to improve the problem of lubricating oil through mechanical friction.
Lubricant replacement instructions
In addition, cold weather will increase the water content in the lubricating oil and affect the service life of the lubricating oil. Therefore, it is recommended that the user appropriately shorten the replacement cycle. It should be noted that the same grade of lubricating oil cannot be used in winter and summer, especially in northern areas where the temperature difference varies greatly. Because the general lubricating oil has a characteristic that the viscosity decreases when the temperature is high, and the viscosity increases when the temperature is low. Therefore, the air compressor should choose the appropriate lubricant according to different seasons (mainly summer and winter), that is, according to different temperatures. There are three commonly used viscosity grades of screw air compressor oil: 32, 46, and 68.
For piston air compressors, the cylinder-packing part uses No. 19 air compressor oil in summer and No. 18 air compressor oil in winter; the crankshaft-connecting rod part uses No. 50 machine oil in summer, and No. 30 and No. 40 machine oil in winter. This can make the air compressor get better lubrication. Generally, single-acting small air compressors use No. 19 air compressor oil in summer and No. 13 air compressor oil in winter.
Due to lack of experience, some users often adopt the method of replacing the lubricating oil after the fault occurs. As a result, the air compressor with the replaced lubricating oil has been running normally for a week or two, and the fault reappears. Such frequent replacement brings a great burden to production costs.
When replacing the lubricating oil, in order to ensure the effect, the air compressor can be started and run for one hour. The purpose of this is to restore the lubricating oil to normal temperature and to do a simple operation for the entire air compressor system (especially the lubricating oil system). Fully cleaning, adding new lubricating oil again can extend its life and significantly improve the performance of the entire compression system.
The maintenance and operation of engineering air compressors used outdoors in winter cannot be ignored. Due to the low ambient temperature, it is difficult to start the construction machinery air compressor. The main reason is: the air temperature at the end of the cylinder compression of the diesel-driven air compressor cannot reach the temperature required for starting, and the compressed air pressure in the cylinder is also significantly lower than the pressure required for starting; the best operating temperature of the battery is 20-40℃ As the ambient temperature decreases, its output capacity also decreases, resulting in a decrease in the power of the diesel air compressor starting system; when the ambient temperature is low, the oil viscosity increases, and the resistance between the frictional negative increases increases, making the diesel air compressor The engine start speed decreases, and at the same time, the viscosity of diesel oil increases, the quality of fuel injection atomization becomes worse, and the ignition lag period is prolonged; the air density and oxygen content in the air decrease with the increase in altitude. The harder the press is to start.
In low temperature conditions, in order to ensure that all kinds of construction machinery can be safely put into use in cold conditions, daily maintenance should be done, and it is best to install a low temperature auxiliary starting system.
Common low temperature start method
1. Choose diesel air compressor oil with good low-temperature performance. This type of air compressor oil has low low-temperature viscosity, good lubrication between friction pairs, and low starting resistance, which is good for starting. ；
2. Use batteries with good low-temperature performance, and heat the batteries if necessary to ensure that they can be charged normally and have sufficient output current under low-temperature conditions, thereby increasing the power of the starting system;
3. Flame preheating start;
4. Add cold start fluid;
5. Circulating water heating system (also known as fuel heater heating system); in addition to the above preheating methods, hot water preheating, steam preheating, electric preheating and other methods can also be used for low-temperature startup.
Improve computer room environment and working conditions
First of all, if conditions permit, it is recommended to put the air compressor indoors or build a temporary tent in winter as much as possible. This can not only prevent the temperature from being too low, but also improve the air quality at the air compressor inlet and maintain the temperature of the air compressor room. Above zero.
Secondly, pay attention to keeping the environment clean and tidy. In particular, pay attention to the fact that there is no water around the equipment and the ground of the station building to prevent ice and slippage, which may cause the operator to fall and be injured.
Operating instructions for air compressors in winter
Before the air compressor is used, we must open the side cover to observe whether the oil thickens or freezes. If so, the oil must be heated first. Even if the oil is not frozen, the oil viscosity of the lubricating parts of the unit is relatively high when the unit is just turned on in winter, and the voltage of some outdoor work sites is relatively low, which is likely to cause relatively difficult startup when the unit is turned on. The general method is to first turn the unit 2-3 times, start the air compressor 3-4 times, and then load the machine after running for a period of time. The current of the air compressor can be measured with a multimeter after its normal operation. Normally, it is within 5% of the rated current of the motor. If it exceeds 10% of the normal current, the unit has a problem or the voltage is low. It should be shut down and checked. Otherwise, the motor will easily heat up and burn out, and will also waste electricity. An important reason for the high current is that the oil starts to block.
After the shutdown in winter, you must pay attention to venting all gas, sewage, and water, and venting the water, gas, and oil in various pipelines and air bags. This is because the temperature of the unit is relatively high when the unit is working in winter. After it is shut down, because the outside temperature is low, a large amount of condensed water will be generated after the air is cooled. , Intercooler blockage, air bag swelling and cracking and other hidden dangers.
At the same time, after cold air enters the air compressor, it will produce a lot of water vapor when it encounters high temperatures, which will increase the burden of the air compressor's post-processing, so it is necessary to frequently discharge the water in the post-processing equipment.
Compressed air enters the production area through pipes and is used by users. Some of these pipes are buried in the ground, and some are erected in the air. Exposed pipes in cold weather may cause part of the moisture to be generated due to the low temperature, and some even increase the moisture, which will affect the normal use of users.
For example, in the laser cutting machine industry, if the compressed air contains high oil and water content, it will affect the accuracy of the cutting process. In the mining industry, humid air compressor compressed air may not affect the normal use of pneumatic tools, but it will affect the strength of pneumatic tools during operation.
Therefore, when off work in winter or when the equipment is shut down, drain valves such as pipes, gas storage tanks, and dryers should be fully opened, and the condensate should be drained before closing the valves.