Plate Type Heat Exchanger Maintenance
1.normal operation and maintenance
(1) For equipment that needs to be repaired, the heat exchanger should be dismantled in reverse according to the installation sequence.
(2)Equipment used in the petroleum and chemical industries shall be repaired regularly according to the maintenance cycle.
(3)The medium in the equipment is explosive or corrosive, and should be inspected at least once a year.
(4)The plate heat exchanger used in other industries,It is best to repair it once every three years if no leakage occurs,
2.Heat Exchanger Plate Cleaning
Chemical cleaning method: The chemical solution is circulated through the heat exchanger to dissolve and discharge the dirt on the phe plate surface .
Mechanical (physical) cleaning method: The plate is disassembled according to the operation manual and manually washed with a brush.
Comprehensive cleaning method: For the case where the scale layer is relatively hard and thick. The scale layer is softened by chemical method first, and the scale layer is removed by mechanical (physical) method to keep the plate surface clean.
Precautions when plate cleaning
I. The solution should maintain a certain flow rate during chemical cleaning, generally 0.8-1.2 m/s. Its purpose is to increase the turbulence degree in the solution.
II. Different chemical cleaning solutions should be used for different fouling. In addition to the frequently used diluted soda ash solution, 5% nitric acid solution can be used for the scale. For the scale generated in the production of soda ash, 5% hydrochloric acid solution may be used, but a chemical cleaning agent which corrodes the plate may not be used.
III. Mechanical (physical) cleaning is not allowed to brush stainless steel plates with carbon steel brushes to avoid corrosion of the plates. At the same time, the surface of plate cannot be scratched or deformed.
IV. The cleaned sheet should be rinsed with water and dried, and the sheet should be prevented from being deformed.
V. The chloride ion content of the cleaning water is ≤25ppm.
3. Heat Exchanger Plate Inspection
(1)Light transmission method: one side puts the light source, and the person checks on the other side.
(2)coloring method: permeation detection according to JB4730.
(3)One-sided pressure test method:After assembling the plate, test the pressure on one side. The other side plate is wet and is damaged.
4.Plate Heat Exchanger Gasket Replacement
(1) Lay the plate that needs to be replaced on the platform, use a flat-blade screwdriver to pick up the gasket gently to be replaced , and then tear off the entire gasket. Be careful not to scratch the gasket groove.
(2) Use acetone, methyl ethyl ketone and other ketone organic solvents to remove the residual glue in the gasket groove.
(3)Wipe the gasket groove and gasket with a clean cloth or cotton yarn.
(4) Apply the adhesive (not containing the chloroprene) evenly in the gasket groove.
Place a clean gasket in the gasket groove on the plate.
Check the gasketed plates one by one to remove excess adhesive. It can be installed and used after being dried for 4 hours in a flat, cool and ventilated place. It is necessary to press heavy objects on the plate when conditions permit.