- Take true countercurrent flow in a shell and tube exchanger as the basis for comparison.
- Tubeside is for corrosive, fouling, scaling and high pressure fluids.
- Shellside is for viscous and condensing fluids.
- Pressure drops are 1.5 psi for boiling liquids and 3-9 psi for other services.
- Double pipe exchangers are competitive at duties requiring 100-200 ft².
- Plate and frame exchangers are suited to sanitary service, and, in stainless steel, are 25-50% cheaper than shell and tube units.