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The heat transfer coefficient of plate heat exchangers affects their heat transfer efficiency, thereby reducing the production efficiency of enterprises. Therefore, how to improve the heat transfer coefficient of plate heat exchangers has become a question that many people want to understand. 1. Increase the heat transfer coefficient on the surface of the plates. As we all know, the corrugations on the plates of plate heat exchangers enable turbulence to occur at lower flow rates, thereby achieving a higher surface heat transfer coefficient. Therefore, the surface heat transfer coefficient of the plate is related to the geometric structure of the plate’s corrugations as well as the flow pattern of the heat transfer fluid. Common types of plate corrugations include herringbone, straight, and spherical shapes. Generally, the herringbone corrugation has a higher surface heat transfer coefficient; moreover, the larger the angle between the corrugations, the higher the flow velocity of the medium in the channel between the plates, and thus the greater the surface coefficient. 2. Reducing the thermal resistance of the fouling layer: The key to reducing the thermal resistance of the fouling layer is to prevent scaling on the plates. When the thickness of the scale on the plates reaches 1 mm, the heat transfer coefficient decreases by about 10%. Therefore, it is very important to monitor the fluid used in plate heat exchangers and to prevent impurities in that fluid from adhering to the plates and causing scaling. If there are viscous impurities in the medium, a specially designed filter must be used for treatment. 3. Choose plates with appropriate thermal conductivity. Stainless steel has good thermal conductivity, high strength, excellent formability, and is resistant to oxidation; however, its resistance to chloride corrosion is relatively low. Therefore, different materials can be selected depending on the operating conditions. Generally, austenitic stainless steel and titanium are the most commonly used materials for such plates. 4. Reducing the thickness of the plates: The thickness of the plates in a plate heat exchanger is not related to its corrosion resistance; rather, it is related to its pressure-bearing capacity and heat transfer coefficient. Increasing the thickness of the plates can enhance the pressure-bearing capacity of the heat exchanger. When herringbone plates are used in combination, adjacent plates are inverted relative to each other, with their corrugations in contact with one another, thus forming particles of large size and uniform distribution. The sealing structures at the corners and edges of the plates have been continuously improved, enabling the heat exchanger to possess excellent pressure resistance. While ensuring that the heat exchanger can withstand the required pressure, a smaller plate thickness should be chosen as much as possible.