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Commissioning of heat exchange equipment: Commissioning of heat exchange equipment refers to the procedures that must be completed by the heat exchangers during the startup of a plant, or the essential requirements that the heat exchangers need to meet in order for the plant to be able to operate. Basic startup procedure for heat exchange equipment: heating up -- bolt pre-tightening -- air displacement -- pre-film treatment on the water side of the cooler. Heating is used to bring the heat exchanger to the basic temperature required by the installation, with steam generally being used as the heat carrier for preheating. The exhaust valve should be opened at the beginning of heating, and closed after steam starts to escape. The drain should be kept in good condition to discharge condensate promptly. The temperature increase should be carried out gradually, such that the heating rate does not exceed 0.06°C/s, and the temperature gradient in the length direction is kept at no more than 30.4°C/m. Bolt pre-tightening: To ensure no leakage of the medium during operation, it is necessary to thermally tighten each bolt on the main sealing surface of the heat exchanger, thereby eliminating any decrease in tightening force that could result from the thermal expansion of the bolts. In bolted connections, the use of properly designed pre-tensioning butterfly springs can effectively prevent a decrease in clamping force caused by the thermal expansion of the bolts. Heat setting can generally be omitted. Air displacement: For devices that require air isolation, the air must be displaced with nitrogen; a nitrogen content of 95% at the vent points of heat exchange equipment is considered acceptable. Pre-film treatment on the water side of the cooler: To ensure that the heat exchanger can operate properly, stably, and over a long period of time in a circulating cooling water system, pre-treatment is necessary before it is put into use. Pre-treatment includes two steps: cleaning and pre-coating. 1) System cleaning: The purpose of cleaning is to remove dirt such as rust, inorganic salts, sediments, and biological sludge from the circulating water system, so that the heat exchangers and other equipment have clean and fresh metal surfaces. This improves the heat exchange efficiency and creates the conditions necessary for pre-coating the equipment. Cleaning should be carried out before starting up the machine, so that after cleaning, a pre-coating treatment can be applied to the cleaned, fresh metal surface; once the pre-coating is complete, normal operation can begin immediately. There are two methods for cleaning: mechanical cleaning and chemical cleaning; it is best to use them in combination. Mechanical cleaning can save on the cost of cleaning agents and reduce waste discharge, while chemical cleaning can remove corrosion products and scale, as well as clean areas that cannot be reached by mechanical methods. 2) Pre-coating: The purpose of pre-coating is to use a pre-coating agent to form a thin, dense protective layer on the clean metal surface, thereby preventing the equipment from being corroded during operation. The pre-coating process should begin immediately after cleaning is completed.