The most detailed introduction to the maintenance skills of the refrigerator

How to repair the refrigerator when it breaks down? A refrigerator is a mechanical device that uses a compressor to change the pressure of refrigerant gas to achieve low-temperature refrigeration. It is useful in many equipment, such as central air conditioning. Generally, the refrigerator uses the tubular heat exchanger to complete the material heat exchange. When the carbon steel tubesheet is used as the cooler, the welds between the tubesheet and the tubular often have corrosion leakage. The leakage into the cooling water system will cause material waste and environmental pollution, and even affect the safety production of the enterprise in serious cases. The corrosion of the welds between the tube plate and the row of tubes of the refrigerator is mainly pitting corrosion and crevice corrosion. There are many corrosion products and deposits on the surface of the tube plate, and bubbles of different sizes are distributed. Galvanic corrosion will also occur when seawater is used as the medium. How do these problems cause the damage of the refrigerator? How should we repair it? How can we find the cause of the failure of the refrigerator? Here is a brief introduction to the quick screen editor.

First of all, we should ensure the lubrication of the refrigerator. The main signs of the normal operation of the lubrication system of the refrigerator are: the oil pressure gauge is stable, the indicating pressure should be 0.05-0.3mpa higher than the suction pressure of the piston or the refrigerator, and 0.2-0.3mpa higher than the condensing pressure of the screw refrigerator. The oil temperature in the crankcase shall be kept between 10-65 ℃, and the most suitable working temperature is 35-55 ℃. 3) The oil level in the crankcase shall be sufficient and stable for a long time. The filter element of the oil filter shall not be blocked, and the fine oil filter with differential pressure signal shall be provided with a blocking signal indication.

If the lubricating system of the refrigerator has problems such as no pressure of the oil pump, failure of pressure regulation and sharp swing of the pointer of the pressure gauge, the reasons may be:

1) The oil temperature in the crankcase is too low, the viscosity of the refrigeration lubricating oil is too high, the filter screen of the oil filter at the inlet of the pump is too dense, the filter element is blocked, and the oil level is too low. It is difficult for the oil pump to absorb oil, resulting in empty suction.

2) The oil pump works for a long time, the pump is severely worn, the internal leakage is too large, and the volume effect is significantly reduced.

3) The pressure regulating valve core is stuck in the open position or the spring of the pressure regulating valve is invalid.

4) Serious external leakage of the system.

The failure of the lubricating part of the refrigerator is not the problem of the lubricating system itself, but it will eventually lead to the failure of the system. For example, improper selection, processing and assembly of the piston ring structure at the cylinder may cause a large amount of oil leakage, and abnormal leakage at the shaft seal will significantly reduce the oil level in the crankcase, thus leading to the empty suction of the oil pump; In addition, if the assembly clearance between the connecting rod large and small end bearing shells and the front and rear main bearings is too small, the lubricating oil is too dirty and the lubricating oil deteriorates after long-term use, which will increase the friction and wear of the moving parts, or at the same time, the high and low pressure blow by due to the severe wear of the cylinder will lead to the heating of the crankcase, the high oil temperature and the low viscosity of the lubricating oil, thus forming a vicious cycle of lubrication conditions and causing the failure of the lubricating system. Therefore, the fault analysis of the lubrication system should be comprehensive, that is, in addition to the problems of the lubrication system itself, the operation status of the refrigerator should be checked, analyzed and judged, such as whether there is abnormal vibration, sound, heat and leakage.

In addition to the failure of the lubrication system, there may also be low cold water flow alarm, refrigerant charge inspection, refrigerant addition, refrigerant extraction, oil level switch disconnection, oil leakage, etc. We should pay attention to oil draining, refueling and oil inspection, and replace the oil filter. These methods are generally found in the operating instructions. We only need to operate according to the instructions. However, please read the instructions carefully before operation.

At the same time, we should also pay attention that the long-term operation of the refrigerator will lead to the equipment being blocked by scale, which will reduce the efficiency, increase the energy consumption and shorten the service life. If the scale cannot be removed in time, it will face the risk of equipment maintenance, shutdown or scrapping and replacement. For a long time, traditional cleaning methods such as mechanical methods (scraping and brushing), high-pressure water, chemical cleaning (pickling) and so on have many problems in cleaning the refrigerator: they can not completely remove deposits such as scale, and cause corrosion to the equipment; the residual acid will cause secondary corrosion or under scale corrosion to the material, which will eventually lead to equipment replacement; in addition, the cleaning waste liquid is toxic and requires a large amount of money for wastewater treatment. The enterprise can use high-efficiency environmental protection cleaning agent to avoid the above situation. It has the characteristics of high efficiency, environmental protection, safety and no corrosion. It not only has good cleaning effect but also has no corrosion to the equipment, which can ensure the long-term use of the air compressor. To learn more about the refrigerator, you can continue to pay attention to the quick access network. The editor will recommend the content you are interested in.