For the inspection of the shell-and-tube heat exchanger, it is very effective to carry out the inspection and maintenance of the partial shell-and-tube heat exchanger for the small problems that occur after the heat exchanger is used for a period of time. This can reduce unnecessary headaches and, more importantly, continue to reuse tubular heat exchangers for extended life.
For partial thinning or other local defects of the shell-and-tube heat exchanger housing, the casing may be partially excavated.
1. The shape of the heat exchanger excavation may be circular or rectangular depending on the specific situation. For the case of excavation, it should be repaired according to the size. If the part to be dug is small, it is suitable to use a circle. If the part to be replaced is relatively large, a rectangle can be used, but the four corners of the rectangle should be processed into a circular arc.
2. The material of the plate welded by the shell-and-tube heat exchanger is very important. The material of the re-welded sheet material shall be consistent with the original shell material and shall be processed to conform to the curvature of the shell.
3. The special position of the tube-and-tube heat exchanger is to open the V-shaped or U-shaped groove to the surface of the tube. The weld should be fully welded or fully welded through the back pad.
4. When the group is paired, it cannot be strongly paired. The amount of misalignment and the angle of the weld should meet the requirements of GB150.
5. Welds are tested with 100% RT.
6. For the shell side pressure is not high, pay attention to the corrosion allowance of the shell when designing, the medium is a mild hazardous medium such as circulating water, the heat exchanger shell of magnesium nitrate can be supplemented with the same material as the shell.
In summary, the problems in the inspection of shell-and-tube heat exchangers are all aspects. The methods of inspection and maintenance of tube-and-tube heat exchangers are also various. The size of partial inspection and repair, the consistency of the shell material, and the full welding. Through or padding, welds in line with GB150, using RT detection, for media considerations. The above are some methods for the maintenance and repair of heat exchangers.