With the development and reform of industry, the position of plate heat exchangers in industry is becoming increasingly important, and they can be found in more and more industries. To ensure the normal operation of plate heat exchangers and extend their service life, it is particularly important to understand and master the common faults of plate heat exchangers, their causes and treatment methods. Below, we will introduce to you the diagnosis and handling of common faults in plate heat exchangers.

(1) The operation status deviates from the process requirements

If the newly put into production plate heat exchanger fails to meet the process requirements, the original design parameters, design calculations, assembly, etc. should be carefully inspected to ensure they are correct. Then, it should be decided whether to increase or decrease the heat exchange area and change the process combination.

If the plate heat exchanger starts to operate normally, but after a period of operation, it deviates from the process requirements, such as: an increase or decrease in pressure drop; The outlet temperature of the medium rises or falls.

The way to deal with this kind of malfunction is:

1. Check whether the inlet parameters of the cold and hot media are consistent with the original design values. If it does not match, efforts should be made to adjust it to the original design value. If the inlet parameters have changed and cannot be adjusted to the original design values, the design calculation should be redone to determine whether to increase or decrease the heat exchange area or change the process combination.

2. If the inlet parameters of the cold and hot media are consistent with the original design values, but the outlet parameters do not reach the design values, the machine should be shut down, and the plates should be disassembled to check for any blockages or scale buildup between the plates, and dealt with promptly.

(2) Leakage occurs in the plate heat exchanger

Due to the long sealing periphery and thin plates of the plate heat exchanger, leakage may occur during use. Leakage phenomena can be divided into two situations: internal leakage and external leakage.

1. Leakage of the plate heat exchanger

Here it refers to the leakage of the medium inside the plate heat exchanger equipment into the external space. This kind of leakage phenomenon is generally easy to detect. The main causes of this kind of leakage are the aging, corrosion or deformation of the gasket. When such leakage occurs, marks should be made on the leaking plate sections, and then the equipment should be disassembled to remove the damaged plates and replace them with new ones.

2. Internal leakage of the plate heat exchanger

This refers to the situation where the two media in the heat exchange equipment leak from the high-pressure side to the low-pressure side due to some reason. This kind of leakage phenomenon is generally not easy to be detected in time. The main causes of this kind of leakage are perforation, cracks and corrosion of the plates. The way to detect this kind of leakage is to frequently test the medium on the low-pressure side and make judgments from the changes in its components.

The shutdown inspection method for this kind of leakage is:

Disassemble the plate heat exchanger, clean the dirt off the plates thoroughly and dry them, then reassemble the heat exchanger. Conduct a hydrostatic test of 0.2 to 0.3Mpa on one side of the heat exchanger. Stop the test immediately after waiting for water to flow out from the other side. Disassemble the heat exchanger and carefully observe the side of the plates that did not participate in the pressure test. The plates that are wet are those with holes or cracks.

(2) On-site, the methods of light transmission and color inspection can also be used to identify the waste plates. All the waste plates and gaskets found during the inspection must be replaced and reassembled for use.