Air compressor high temperature and problem solving: For customers, if the air compressor high temperature problem occurs, they should consult the after-sales service department of the relevant manufacturer at the first time to determine whether it needs to be shut down for repair to prevent safety accidents. For air compressor maintenance personnel, it is particularly important to know how to solve the problem of high temperature of the air compressor. Because, high temperature problem is one of the most common failures of air compressors.
High temperature has a great relationship with the environment of the air compressor station. Most of the related high temperature problems are directly or indirectly related to the poor environment of the air compressor. This article discusses the problems that occur in the air compressor itself other than the environment.
The air compressor is a transmission machine. If the equipment running at high speed is not properly lubricated or cooled, it will inevitably generate high temperature. Too high temperature will change the physical coefficient values of the rotor and bearing materials, and in severe cases, the entire main engine will be scrapped. . Although air compressor manufacturers have installed protective devices for high temperature, the existence of faults will cause the protective devices to operate frequently and affect the normal production of customers.。
There are many situations that cause the high temperature of the air compressor. Blindly looking for the root cause of the failure is not only low-efficiency, waste of human and material resources, but more importantly, it leaves an unprofessional impression on customers, and even loses the opportunity for next cooperation.
This site has been researching and exploring the fault for many years. After many on-site operations, a set of methods for quickly finding the source of high temperature faults for oil-injected screw air compressors have been integrated for your reference:
First of all, let's understand the temperature of the oil-injected screw air compressor: usually the oil-injected screw machine should work at 65~98 ℃, and the oil temperature is too low, which will affect the decomposition of oil and water, resulting in oil emulsification and reducing the lubricating oil. The high oil temperature will reduce the gas transmission coefficient and increase the power consumption, the viscosity of the lubricating oil will decrease, causing abnormal friction loss of the bearing, and even the accident of bearing loose balls. Thermal decomposition occurs under catalysis, generating free carbon, acids and moisture (carbon deposition) that are harmful to the work, and in severe cases, the screw will be stuck.
The oil circulation process can be understood as two paths, That is, the air end to the oil and gas separation tank to the oil and gas separator to the one-way valve to the air end; and the other oil circuit can be divided into two processes, That is, the air end to the oil and gas separation tank to the temperature control valve to the oil filter to the air end. When the temperature exceeds the action value of the temperature sensing element of the temperature control valve (usually at 71°C), the oil circuit circulation process is as follows: Air end to oil and gas separation tank to temperature control valve to oil cooler to temperature valve (confluence) to oil filter to air end.
If all of the above are understood, then we can enter the topic to analyze the temperature difference of the connecting pipes (A, B, C, D pipes) of the temperature control valve to determine the source of the high temperature:
1) At high temperature: First of all, it is necessary to rule out whether it is the fault of the air end itself. The judgment method is:
Find out if the machine head has been overhauled recently, whether the lubricating oil is genuine, whether the engine oil is too low, turn the rotor by hand after turning off the machine, whether it feels stuck, After turning on the machine, check whether the vibration of the whole machine is too high and whether there is any abnormal noise in the machine head.
If the high temperature is caused by the above reasons, the oil circuit should be normal, and the temperature values of points A and C of the oil pipe are close. Because the equipment is at a high temperature, the temperature control valve is in a fully working state, and the temperature difference between points D and B is also close, and is significantly lower than points A and C (the normal temperature difference can be calculated by parameters such as fan, cooler material, heating area, etc. );
Note: Points D and B are connected in any case. Some temperature control valves only have three ports, while point D is directly connected to pipe B with a tee.
Analysis: At this time, the temperature control valve is in a normal state, and the lubricating oil flows from the oil and gas separation tank to points A and C, and then flows to points D and B after being cooled by the cooler. After the oil converges at points D and B, it flows to the oil filter for oil purification. Finally, return to the air end, so the oil temperature difference at this time should be A≈C. Because the equipment is in a high temperature state, the solid temperature control valve is in a fully open state, so D≈B, A, C > D, B;
2) At high temperature: If the temperature of D and B points is excessively lower than that of A and C, check whether the oil filter is blocked at this time;
Analysis: Oil filter blockage: In this case, the oil circuit is the same as the above, except that after the oil filter is blocked, the flow of lubricating oil is reduced. The temperature at point B is very different from the temperature at points A and C. The high temperature is because there is too little oil to the nose to meet the amount of oil required for cooling the nose.
3) When the temperature is high, the temperature of point D is slightly lower than that of point B, and the temperature of point B is only slightly lower than that of points A and C, the temperature control valve spool cannot be fully opened, and the temperature control valve should be checked at this time;
Analysis: The above has analyzed the condition of the oil circuit in the normal state. If the temperature of point D is slightly lower than that of point B, and the temperature of point B is only slightly lower than that of points A and C, it proves that the temperature control valve spool cannot be fully opened. The lubricating oil should flow from the oil and gas separation tank to point A, part of the lubricating oil to point C, and part of the lubricating oil to point B. The oil at point C is cooled by the cooler and flows to point D and point B to join, and then flows to the engine through the oil filter. head, so A≈C > B > D;
4) When the temperature is high, the temperature of points D and B is slightly lower than that of points A and C. At this time, check the cooling system of the cooler;
Analysis: The cooling effect of the cooler is not good: at this time, the lubricating oil should flow from the oil and gas separation tank to points A and C through the cooler to points D and B, and then flow to the machine head through the oil filter, because the cooler cannot fail 100%. , so A, C and D, B still have a slight temperature difference, so A≈C > D≈B;
5) When the temperature is high, if the temperature of points A, B, and D is close, and the temperature of point C is significantly lower than that of points A, B, and D, it proves that the temperature control valve is not working;
Analysis: The temperature control valve does not act: At this time, the oil circuit flows from the oil and gas separation tank to point A. Because the temperature control valve does not act, the oil at point A flows directly through the oil filter to point B, because point B and point D are connected to the pipeline, D Point is connected to point C but there is a cooler in the middle, so A≈B≈D > C;
6) When the temperature is high, such as the temperature values of points A, B, C, and D are close, there are many reasons at this time, such as the radiator does not work, the cooling fan does not work, etc.
Analysis: The radiator does not work (for example, the wall of the radiator is seriously fouled): At this time, the lubricating oil flows from the oil and gas separation tank to points A and C, and flows to points D and B through the cooler, and the oil flows to the oil after the confluence of points D and B. The filter purifies the oil, and finally returns to the air end. Because the cooler does not play a role in heat dissipation, solid A≈C≈D≈B;
Cooling fan does not work: This fault can be seen by the naked eye, and the oil circuit is the same as the oil circuit where the radiator does not work.
