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Generally, new equipment does not need to be disassembled; the heat exchanger is only opened for mechanical cleaning, replacing gaskets, identifying the cause of leaks, or modifying the equipment. 1. Removing the plates: Before opening the heat exchanger, first check that the cold and hot media have been completely drained. Loosen and remove the connections on the movable clamping plate (if any). It is necessary to first relieve 25% of the load on each clamping bolt before removing them; the marking bolts should then take over the clamping load. To prevent the plates from shifting out of place, the inclination of the clamping plate surface should not exceed 10 mm when the marking bolts are loosened. Remove the bolts to take away the movable pressing plate; the plate can be removed easily. 2. Installing the plates Arrange the plates according to the design diagram; ensure everything is correct before clamping them, and then clamp them in the specified order. When tightening the clamping bolts, it is necessary to follow the specified procedures: the bolts should be tightened in a diagonal pattern in sequence 1, 2, 3, 4, so as to maintain the parallelism of the plates. In other words, the plate assembly is first clamped to the appropriate length using the four marked bolts, after which the remaining bolts are inserted and tightened to the specified torque. When the heat exchanger has been in use for a short period, within one year, the upper limit of the clamping size can be chosen ； It can be tightened to a smaller size after long use, but not below the minimum size, to avoid damaging the plate and gasket. 3. Hydrostatic test A hydrostatic test must be conducted on the plate heat exchanger after it has been assembled. Hydraulic testing shall be carried out separately on each side. The test pressure shall be 1.25 times the working pressure; it is considered successful if the pressure remains stable for 30 minutes without dropping. 4. Replace the plates – Defective plates should be replaced. The new plates replaced should be exactly the same as the old ones, with the same arrangement as well. If there are no spare parts on site and the machine cannot be stopped, simple on-site repairs should be carried out. The method involves removing the damaged plates in pairs; if the number of such plates is not large and the resulting reduction in the number of flow channels is minimal, the machine can continue to be used after assembly. The impact on production won’t be too great. 5. Replace the gasket: For the plates removed from the frame, accurately record their arrangement and the type of sealing used for the gaskets. Remove the old gasket from the seal groove and thoroughly clean the seal groove. Residual glue, grease, and other foreign substances in the grooves can be cleaned by using a brush dipped in solvents such as acetone, butane, or other similar solvents. If the medium to be treated is juice, beer, milk, etc., clean it first with hot water containing a detergent, and then scrub it with a solvent. The gaskets are bonded in accordance with the specified bonding process for the designated type of adhesive. Do not use adhesives of any grade for bonding, to avoid issues such as plate corrosion and medium contamination. 6. Replace the corner seal sleeve: When the seal sleeve is damaged, it should be removed immediately. To install a new one, press it flat radially by hand and then insert it into the hole of the pressing plate. Note: The diameter of the groove on the inner side of the pressing plate should match the diameter of the rubber sleeve; do not put the rubber sleeve on backwards.