| |
Traditional
PHE |
Shell
& Tube heat exchanger |
| Temperature cross |
possible |
Impossible |
| Temperature approach |
1℃(2 °F) |
5℃(10 °F) |
| Multiple duty |
Possible |
Impossible |
| Piping connections |
From one direction
(on frame plate) |
From several direction |
| Heat transfer ratio |
3 - 5 |
1 |
| Operating weight ratio |
1 |
3 - 10 |
| Hold - up volume |
Low |
High |
| Space ratio |
1 |
2 - 5 |
| Welds |
None |
Welded |
| Sensitivity to vibrations |
Not sensitive |
Sensitive |
| Gaskets |
On every plate |
On each bonnet |
| Detection of leakage |
Easy to detect on exterior |
Difficult to detect |
| Access for inspection |
On each side of plate |
Limited |
| Time required for opening |
15 minutes
(with pneumatic tightener) |
60 - 90 minutes |
| Repair |
Easy to replace plate
and/or gasket |
Requires tube plugging
= decreasde capacity |
| Modification |
Easy by adding or
removing plates |
Impossible |
