Analysis of several common problems in the maintenance of imported plate heat exchangers_
Analysis of several common problems in the maintenance of imported plate heat exchangers
Analysis of several common problems in the maintenance of 844 imported plate heat exchanger. The plate heat exchanger is an important part of the refrigeration host. It is composed of a set of corrugated metal plates. The plate has four corner holes for The two liquids for heat transfer pass through and guide the fluid to alternately flow through their respective channels for heat exchange. They are tightly arranged, high precision, small in size, high in heat exchange efficiency, space-saving, and high in environmental requirements. They are suitable for small-scale refrigeration. Used on the unit. General equipment can be used for 15 to 20 years under normal maintenance and maintenance, but the main reason for the breakdown of the plate heat exchanger of the host is as follows: 1. Maintenance problem The plate heat exchanger is heat exchange in process industrial equipment An important part of technology. The elastic gasket that seals between the various plate fins is a vulnerable part, and it is also a part that is prone to aging under natural conditions. Its service life has an important influence on the service life of the plate heat exchanger. If these gaskets are hardened and lose their original elasticity, and if they are re-tightened or replaced in time, the heat exchanger may leak. In addition, the plate heat exchanger needs to be cleaned regularly after a long period of operation, usually once every two years. For example, the current plate heat exchanger can be disassembled and cleaned individually, but the plate heat exchanger on the main engine of this project cannot be disassembled. It can only be done by opening the valves and plugs on the inlet and outlet pipes of the heat exchanger. It is difficult to clean the heat exchanger, and it is easy to block and scale. Once a part of the passage in the heat exchanger is blocked, the remaining passages have to withstand the flow of all the water of the unit, so that it flows through the plate heat exchanger. As the flow rate of the filter increases, the friction force increases, and the wear speeds up. 2. Quality problem Compared with the heat exchange surface of other heat exchangers, the heat exchange surface of the plate heat exchanger is quite thin, namely 0.5mm, and the allowable corrosion degree is 0.05mm/year. Ordinary plate heat exchangers are usually made of alloy materials (304 or 316). 304 is one of the cheapest austenitic stainless steels. It has corrosion resistance to a certain range of organics, but has weak resistance to hydrochloric acid and sulfuric acid. The material of the plate heat exchanger of the main unit of the air conditioner of this project is 304, so after 8 years of use, the plate will break down and corrode is inevitable. 3. Construction problems. Only the 'Y' filter is installed in the system, and there is no electronic water treatment device, so it is difficult to ensure that the piping system does not scale. In addition, if the 'Y' type filter is not cleaned up in time, there will still be small grit remaining in the circulating water even if it is not harmful to the shell and tube heat exchanger, but it will also cause damage to the plate heat exchanger.