How to deal with the aging of heat exchanger plates?

The softening of the plate gasket of the heat exchanger is related to the pressure and temperature. When the gasket loses elasticity, the heat exchanger will drip. In some products, in order to solve the leakage caused by the aging of the sealing gasket, the sealing performance of the heat exchanger is allowed to be adjusted, that is, the bolts of the combined plate heat exchanger are tightened again, and the pressing force of the elastic sealing gasket between each heat exchanger is adjusted to solve the leakage problem.

The nameplate of heat exchanger with this function generally gives the allowable Zui large and Zui small stress. For new heat exchanger plate groups, Zui small allowable stress shall be used for connection and fixation. Depending on the number of heat exchanger plates in each group, the tightening force of the heat exchanger can be adjusted once or several times. During each tightening, the nut can be screwed in for 3mm, and the stress of the adjusting plate shall be always paid attention to during the tightening process. In addition, it is only allowed to adjust the tightening force of the heat exchanger without working pressure at room temperature to prevent leakage.

For the plate heat exchanger without the stress adjustment range in the nameplate, the stress value is generally given in the part drawing. When tightening this kind of plate heat exchanger, the tightening torque shall not be lower than the value specified in the drawing, because it is related to the assembly quality and assembly deformation of the plate heat exchanger. When the tightening torque meets the requirements of the specified value, the elastic gasket can be replaced in a planned way. For plate heat exchangers used in important production equipment and corrosive media, it is recommended to have a set of spare seals. When the warehouse temperature is 18 ℃, the seals of the plate heat exchanger can be stored for about 3 years in transparent plastic packaging.