How to remove the scale of the super tube and shell condenser of the low temperature refrigerator?

2019-04-20 11:31:26
How to remove the scale of the super tube and shell condenser of the low temperature refrigerator?
After using the low-temperature refrigerator for a long time, you need to pay attention to the maintenance of various parts, especially the scale problem of the shell-and-tube condenser. If it is not solved in time, the scale will affect the heat dissipation problem of the low-temperature refrigerator. Shell and tube condensers need to be cleaned of scale in time.

Generally speaking, we have 3 methods to remove the scale of the ultra-low temperature condenser of the low-temperature refrigerator. They are mechanical descaling, chemical pickling descaling and electronic magnetic water heater descaling.

1. Mechanical descaling is a method of descaling the condenser of the cooling tube using a flexible shaft tube washer, and is especially suitable for vertical shell and tube condensers. The specific operation is to first extract the refrigerant in the condenser, then close all the valves connected to the condenser and the refrigeration system to ensure the normal supply of cooling water to the condenser, and then use the bevel gear-shaped scraper connected with the flexible shaft tube washer The vertical tube of the condenser is rotated and scraped from top to bottom to remove the scale, and the heat generated by the friction between the scraper and the tube wall is cooled by circulating cooling water, and the removed scale, rust and other dirt are flushed into the pool. When cleaning the ultra-low temperature shell-and-tube condenser of the low-temperature refrigerator, care should be taken to prevent damage to the tube wall and avoid the failure of the ultra-low temperature of the low-temperature refrigerator.

2. Chemical pickling descaling is to use a prepared weak acid descaling agent to clean the ultra-low temperature condenser of the low-temperature refrigerator to make the scale fall off and improve the heat transfer efficiency of the condenser. First, prepare the descaling solution in the pickling tank and activate the acid Wash the pump and make the descaling solution circulate in the condenser tube of the condenser for 24 hours. Generally, after 24 hours, the scale is basically removed. Then stop the pickling pump and use a round steel brush on the condenser tube. Pull back and forth inside the pipe wall, and wash away the scale and rust with clean water, and then repeatedly wash the descaler solution remaining in the pipe with clean water until it is completely clean. The chemical pickling and descaling method is suitable for vertical and horizontal shell and tube types Condenser.

3. The electronic magnetic water descaling method is to dissolve the calcium, magnesium and other salts in the cooling water flowing through the condenser in the state of positive and negative ions in the water at room temperature, which can effectively prevent the generation of new scale and remove the original At the same time, due to the different expansion coefficients of the steel pipe in the condenser and the scale, the original scale gradually cracks, and the magnetized water continuously penetrates into the cracks, destroying the adhesion of the original scale, and gradually loosening it. It falls off by itself and is constantly taken away by the circulating cooling water.

Once the ultra-low temperature condenser of the low-temperature refrigerator has scale, the heat conduction resistance will continue to increase, resulting in a continuous decrease in the heat transfer coefficient value, which makes the cooling effect worse and worse. Therefore, once the condenser is found to have scale, it must be checked in time Remove scale.