How to clean air cooler and cooler leak test method?


Most engineering machinery and equipment use heat-dissipating products that use hydraulic oil as a heat transfer medium. For example, it is an essential equipment in excavators, road rollers, trenchers, etc. The main function of the air cooler is to reduce the circuit. The temperature of the hydraulic oil to prevent high temperatures from affecting the normal use of the machine.


During the process of use, iron scrap was found in the hydraulic system of the excavator. Although the fuel tank was cleaned, the pipeline was cleaned and a strong magnet was placed in the hydraulic tank, but the repairman said that it could not be cleaned because of wind cooling. There may also be iron filings inside and outside the unit, even if the radiator is replaced. How should I solve this situation? At this point, the oil should be cleaned, and the white surface and water should be used to adjust the image to make the hoe like soft and hard. Then use it to roll back and forth in the fuel tank, and press it everywhere to remove the iron filings.


Traditionally, we have used water to test the leak of the cooler, that is, to inject water into the cooler, and then fill the water, then use the water pump to pressurize the water in the cooler to make it reach a certain pressure, and check the cooler. . After the leak is finished, mark and release the pressure and drain, and then stop the leak. If the cooler is large and the leakage is serious, the water pressure will leak when it is low, and it has to be drained to stop the leak. After the plugging is completed, the water is filled again, the pressure is tested and the leak is repeated, and the maintenance time of the cooler is increased. Since a large amount of time is required for water filling and pressing, and the leaked part needs to be repaired by dynamic fire repair, the leaking part should be dried, otherwise the quality of repair welding leakage is affected. If there is flammable medium inside the leaking cooler, it must be replaced by nitrogen. After passing the test, it can only be repaired by welding and leakage. Otherwise, fire and explosion will occur, which will endanger the safety of people and equipment.


After the air cooler leaks, the nitrogen gas is used for the pressure test leak, which is relatively fast. When the cooler is used to block the hot and cold operation of the cooler, it is not necessary to perform the replacement treatment, thereby saving the time for inspection and leakage. The main points of operation of nitrogen in the test leak of ammonia cooler are as follows:


1. Because it is high-pressure nitrogen (pressure 9.5MPa), it is necessary to have more than 2 people to open the valve when using, and install a pressure gauge in the middle of the two valves.


2. One person monitors the pressure gauge and the other performs the valve opening operation to ensure that the pipeline pressure is within the allowable range to prevent overpressure and cause pipeline or personnel injury.


Safety precautions for nitrogen leak test: Because nitrogen has the risk of suffocation, personnel must pay attention to the safety of personnel and prevent personnel poisoning; nitrogen should be pre-fabricated in advance when using nitrogen; pressure gauge should be added to temporary pipeline when nitrogen is used, two people Use the walkie-talkie to open the valve to prevent overpressure; after the use of nitrogen, the pressure must be relieved and removed in time; when using nitrogen, more than 2 people must use the walkie-talkie to contact the charging and pressure relief operation to prevent the pipeline from overpressure, damage the pipeline, and prevent people from suffocating. Cause personal injury.