The common faults and treatment of
heat exchangers are shown in Table 2-2.
| No. |
Fault |
Cause |
Solution |
| 1 |
Two kinds of media mingling together (internal leakage) |
- Corrosion perforation and cracking of heat exchange tubes
- Cracking of the expansion mouth (welding mouth) of the heat exchange tube and tube plate
- Sealing leakage of float head flange heat exchangers
- Sealing leakage of tight-ring type heat exchanger tube plates
|
- Replace or block the leaky tube.
- Expand again (repair welding) or make blockage.
- Fasten bolts or replace sealing gaskets.
- Tighten inner ring compression bolts or replace packing (gaskets).
|
| 2 |
Flange seal leakage |
- Gaskets are under pressure, corrosion and deterioration.
- Bolts are weak, loose or corroded.
- Flanges lack of rigidity with sealing surface defects.
- Flanges are not parallel or misaligned.
- The gasket is of poor quality.
|
- Tighten the bolt and replace the gasket.
- Upgrade Bolts material, fastening or replacing bolts.
- Replace flanges, or deal with their defects.
- Repair or replace the flange.
- Replace the gasket.
|
| 3 |
Poor heat transfer effect |
- Heat exchange tube scaling
- Poor water quality, oil pollution and microorganisms
- Clapboard short circuit
|
- Remove scale by using chemical cleaning or jet cleaning method.
- Strengthen filtration and purification of media so as to strengthen water quality management.
- Replace the pipe box gasket or the partition.
|
| 4 |
Resistance exceeding allowable value |
- Filter failure
- Scale formation inside and outside the casing and the pipe
|
- Clean or replace the filter.
- Clean the scale by jet or chemicals.
|
| 5 |
Severe vibration |
- Resonance caused by medium frequency
- Resonance caused by external pipe vibration
|
- Change the flow rate or the natural frequency of the bundle.
- Reinforce the pipe to reduce vibration.
|
Table 2-2 Common failures and treatment of heat exchangers
