The newly purchased heat exchanger has been installed as a whole and can be installed as a whole. If it is not necessary, it shall not be disassembled. The removal and reinstallation of plate heat exchanger are very meticulous work, which should be carried out by experienced personnel according to certain rules to ensure good sealing and normal use after installation. Improper assembly, disassembly and installation will cause poor sealing and even plate deformation and damage, which is difficult to recover. Before dismantling the heat exchanger, the original thickness of the plate group shall be measured with a steel ruler at the upper, lower, left and right corners of the equipment and recorded. This thickness shall be restored as much as possible during re installation. If the number of plates is increased or decreased, the correct total thickness shall be calculated first. For example, with 80 BR50 plates, the nominal thickness is 80 × (３．８+0.６)=３５２mm 
The difference between the thickness after installation and compaction and the nominal value shall be less than 1%, and the thickness of the above example shall be 347~357mm. Plate heat exchanger is usually compressed into a whole with 6~12 bolts. During assembly and disassembly, these bolts shall be tightened or loosened evenly and evenly without uneven tightness.
When removing the loosening bolt, loosen the middle bolt first and then the four corners. At the beginning, it should be 1~2 turns each time, more later, and repeated several times until it is completely released. During the relaxation process, the total thickness of the plate shall be measured at the four corners. The left and right deviations shall not exceed 10mm, and the upper and lower deviations shall not exceed 25mm.