The cold dryer is the abbreviation of the freeze dryer. The dryer is a new type of technology and belongs to the air source treatment component in the pneumatic system.
First, the intake air temperature is too high, the intake air amount is large
When the intake air temperature is high, the cold-drying machine will not react very quickly to the high temperature when it is processed. If the intake air temperature is lowered in a timely and effective manner, the exhaust gas temperature will naturally rise.
The temperature of the inlet and outlet of the dryer is determined by the compressor discharge temperature. When the compressed air exhaust temperature is high, the cesium generally enters the chiller through the secondary cooling of the buffer tank, but some of the buffered tanks do not have a dedicated buffer tank. Direct entry into the dryer causes the inlet air temperature of the dryer to be higher.
The reason for the high exhaust temperature of the compressor is that the main reason is that the cooler is poor or malfunctioning. Sometimes it may be that after the compressor has been running for a certain period of time, the scale inside the water-cooled compressor cooler is too large, and the cooler is blocked, causing the exhaust gas temperature to increase. The clogging of the cooler scale is generally not easy to be taken seriously, especially the screw unit. Because the circulatory water used by the ‚ screw unit is generally the case of the net circulating water, the situation is more than that of the circulated water. less,
Therefore, the scale of the sputum formation is relatively slow, but there is also the possibility of scale formation. Once the formation of the scale is not detected in time, it will produce high temperatures. The phenomenon that the exhaust gas temperature is too high can be eliminated only after the scale is cleared. Oil filter and oil-water separator blockage can also cause high-temperature oil filter and oil-water separator to be composed of paper fiber-like material and mesh. These materials can effectively filter particles and other impurities in air and grease. And the precipitation of impurities toward the bottom of the filter is discharged as waste oil water. However, this kind of failure is sometimes not easy to be found. Sometimes impurities are adsorbed on the fiber cotton and it is not easy to be clear. This blocks the oil filter and oil water filtration. Device. When the filter fails, the exhaust temperature of the compressor rises. At this time, it is necessary to replace the oil filter and the oil-gas separation filter in time.
However, some machines have replaced the new oil-gas separation gas cylinders in time. The exhaust gas temperature is still very high. There are two possibilities here: one is that the alarm with high exhaust gas temperature is not released at the time. The alarm system is not recognized, even if the filter element is replaced. It is also an alarm, but this alarm is a false alarm, just remove it on the operation panel. Some operators do not know this situation, or know that they dare not operate or operate because some of them are displayed in English, which causes trouble for identification. There is another type of problem, that is, some compressors are very sensitive to the design of the oil separator. The upper part is the lower part of the gas cylinder. The lower part is the fault on the oil pan operating panel. It is not the oil alarm or the gas alarm. Both types of alarms affect the normal operation of the equipment. This alarm can only be eliminated after the pressure balance of the oil and gas. But it's not easy to really eliminate it. This situation can also cause false alarms on the exhaust temperature. Another is that the heat sink of the air cooler has a thicker dust, which causes it to fail to dissipate heat properly.
In addition, the large amount of intake air makes it impossible for the dryer to handle so much compressed air as soon as possible. It can only be quickly discharged after being treated with sloping sputum. Under such circumstances, the venting temperature of the chiller naturally increases. The amount of compressor displacement is sometimes related to the pipe network system of the compressor. It is possible that when the air volume is small, the displacement of the compressor is not adjusted in time, resulting in an increase in the displacement. Generally, the frequency conversion technology should be used. Adjust the displacement of the compressor. However, most of the existing compressors do not have a variable frequency technology, and it is quite difficult to automatically adjust the intake air volume of the compressor. If the qualified enterprise can transform the compressor into the frequency conversion technology, the general frequency conversion technology transformation needs 10,000 to tens of thousands of dollars to ignore the size and difficulty of the compressor to determine the cost of its frequency conversion technology transformation is generally three months. The investment can be recovered within a few years. This is a way to solve the problem of excessive exhaust gas temperature in the dryer. It is also a good way to save energy and save electricity.
Second, the high pressure of refrigerant
The cold dryer uses a cooling device such as Freon and the like to dry the compressed air. The refrigerant has higher requirements on the working conditions and the external environment. For example, the flow rate of the circulating water of the water-cooled unit will change the pressure and temperature of the refrigerant. . The increase in water temperature and the decrease in water flow can directly lead to an increase in refrigerant pressure. When the pressure generally rises to 0.18 MPa, the refrigerant pressure reaches the upper limit and the cold-drying unit automatically shuts down.
When the pressure of the refrigerant increases, the exhaust pressure and the exhaust temperature of the cold-drying unit increase. In this case, the cooling effect of the refrigerant system of the dryer is lost. The high temperature of the compressed air cannot be effectively and effectively treated. The quality of the air is affected to a certain extent. If the user's process requirements are high, then this compressed air is a substandard product. The product produced by the customer will also be waste, and its economic loss is very large.
Third, the pre-cooler pipe heat dissipation is large
The pre-cooler mainly relies on the heat dissipation of the pipeline. Because the compressed air expands after the compression process, it has a certain high temperature. It must be cooled after several steps to reach the normal use standard. The pre-cooler is one of the dryers. As long as the part ‚ compressed air is cooled by this part, the heat dissipation of the pipeline of the pre-cooler will increase, and the cooling effect will be affected, and the exhaust temperature will increase accordingly. The exhaust gas temperature of the dryer is too high, which affects the quality of the compressed air product. Therefore, when looking for the cause of high exhaust gas temperature of the dryer, the heat dissipation of the pre-cooler pipe is a factor that cannot be ignored. The solution is to check the pre-cooler and find out the problem that the heat dissipation of the pipeline is large.