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Disassembly sequence: (1) When the heat exchanger has insulation, first remove the tube box and the insulation of the large cover； Note that to reduce costs, the insulation material for all heat exchangers can be reused; therefore, care should be taken to avoid damaging it during removal. The removed insulation should be marked with a marker indicating the heat exchanger’s location, and then stored together in one place. (2) Remove the inlet and outlet flange bolts, then disconnect the equipment connection pipes ； When removing, be careful not to damage the flange surface. The removed parts should be placed nearby and properly marked to facilitate reinstallation ； The bolts should be stored separately, properly labeled, and kept together for easy reinstallation. (3) Use special tools to remove the end caps, being careful not to damage the flange surfaces as well. The removed parts should be placed nearby and properly marked to facilitate reinstallation ； The bolts should be stored separately, properly labeled, and kept together for easy reinstallation. (4) Use special tools to pull out the tube bundle for cleaning. Precautions: (1) Before disassembling the heat exchanger, the compression length of the plate bundle should be measured and recorded; this dimension should be followed when reassembling it. (2) When performing core extraction inspections on heat exchangers, the core extraction machinery should possess sufficient pulling and pushing force, be capable of automatic centering, have a stable center of gravity, operate smoothly, and be safe and reliable. (3) When removing the core from the heat exchanger, the removed components should be properly labeled and stored carefully. (4) When lowering the heat exchanger core from the core extractor to the ground, the tube bundle must not be directly tied up using steel wires or other sharp lifting tools; when the tube bundle is placed horizontally, it must be supported on tube sheets or support plates. (5) When lifting the heat exchanger, personnel involved in the lifting operations must hold valid certificates to work. (6) When lifting the heat exchanger, there must be a designated supervisor. This supervisor should be a person with extensive practical experience, high technical skills, and strong organizational abilities. The supervisor should wear a distinctive marker or a safety helmet of a special color, and must fully understand and strictly adhere to the provisions outlined in the lifting construction technical documents. (7) When directing the lifting of heat exchangers, one should stand in a position from which it is possible to give instructions to all work stations; otherwise, signals should be transmitted promptly through assistants. The signals used must be pre-agreed upon, and they need to be accurate, loud, and clear. (8) Lifting of the heat exchanger should be stopped in case of thunderstorms, heavy snow, low visibility, or wind speeds exceeding 10.8 m/s. (9) All personnel are strictly prohibited from staying or walking under the crane arm and the lifted load. (10) When using snap rings, force should be applied in the length direction; snap rings are used to prevent the pins from slipping, and defective snap rings must not be used. (11) Interlaced steel wire ropes should be used for lifting objects. If the wire rope exhibits abnormalities such as kinking, deformation, broken wires, or rust, its usage standards should be reduced promptly or it should be discarded. (12) The crane positions shall be set according to the specifications and locations specified in the construction plan; if trenches, wells, underground pipelines, or similar conditions are found, the person in charge of the construction site shall be informed promptly so that measures can be taken. Inspection items: After the heat exchanger is disassembled, it is necessary to inspect each of its components in order to identify defects promptly, mark them, and take appropriate actions to address them. The main inspection items include the following: (1) Clean the tube bundle housing. (2) Visually inspect the shell, tube bundle, and components for corrosion, cracks, and deformation; surface testing and eddy current testing may be used for spot checks if necessary. (3) Check whether the anti-corrosion layer is aged or peeled off. (4) Inspect the lining for corrosion, bulging, wrinkles, and cracks. (5) Check the sealing surface and gasket. (6) Check for damage to the fasteners. High-pressure bolts and nuts should be cleaned and inspected one by one, and non-destructive testing should be carried out if necessary. (7) Check whether the foundation is sunken, tilted, damaged, or cracked, and whether other anchor bolts, shims, etc. are loose or damaged.