| Type Designation | Significant Feature | Applications Best Suited | Limitations | Relative Cost in Carbon Steel Construction |
| Fixed Tube Sheet | Both tube sheets fixed to shell | Condensers; liquid-liquid; gas-gas; gas-liquid; cooling and heating, horizontal or vertical, reboiling | Temperature difference at extremes of about 200°F. Due to differential expansion | 1.0 |
| Floating Head or Tube Sheet (Removable and nonremovable bundles) | One tube sheet “floats” in shell or with shell, tube bundle may or may not be removable from shell, but back cover can be removed to expose tube ends. | High temperature differentials, above about 200°F. extremes; dirty fluids requiring cleaning of inside as well as outside of shell, horizontal or vertical. | Internal gaskets offer danger of leaking. Corrosiveness of fluids on shell side floating parts. Usually confined to horizontal units. | 1.28 |
| U-Tube; U-Bundle | Only one tube sheet required. Tubes bent in Ushape. Bundle is removable. | High temperature differentials which might require provision for expansion in fixed tube units. Clean service or easily cleaned conditions on both tube side and shell side. Horizontal or vertical. | Bends must be carefully made or mechanical damage and danger of rupture can result. Tube side velocities can cause erosion of inside of bends. Fluid should be free of suspended particles. | 1.08 |
| Kettle | Tube bundle removable as U-type or floating head. Shell enlarged to allow boiling and vapor disengaging. | Boiling fluid on shell side, as refrigerant, or process fluid being vaporized. Chilling or cooling of tube side fluid in refrigerant evaporation on shell side. | For horizontal installation. Physically large for other applications. | 1.2-1.4 |
| Double Pipe | Each tube has own shell forming annular space for shell side fluid. Usually use externally finned tube. | Relatively small transfer area service, or in banks for larger applications. Especially suited for high pressures in tube above 400 psig. | Services suitable for finned tube. Piping-up a large number often requires cost and space. | 0.8-1.4 |
| Pipe Coil | Pipe coil for submersion in coil-box of water or sprayed with water is simplest type of exchanger. | Condensing, or relatively low heat loads on sensible transfer. | Transfer coefficient is low, requires relatively large space if heat load is high. | 0.5-0.7 |
| Open Tube Sections (Water cooled) | Tubes require no shell, only end headers, usually long, water sprays over surface, sheds scales on outside tubes by expansion and contraction. Can also be used in water box. | Condensing, relatively low heat loads on sensible transfer. | Transfer coefficient is low, takes up less space than pipe coil. | 0.8-1.1 |
| Open Tube Sections (Air Cooled) Plain or finned tubes | No shell required, only end heaters similar to water units. | Condensing, high level heat transfer. | Transfer coefficient is low, if natural convection circulation, but is improved with forced air flow across tubes. | 0.8-1.8 |
| Plate and Frame | Composed of metal-formed thin plates separated by gaskets. Compact, easy to clean. | Viscous fluids, corrosive fluids slurries, High heat transfer. | Not well suited for boiling or condensing; limit 350-500°F by gaskets. Used for Liquid-Liquid only; not gas-gas. | 0.8-1.5 |
| Spiral | Compact, concentric plates; no bypassing, highturbulence. | Cross-flow, condensing, heating. | Process corrosion, suspended materials. | 0.8-1.5 |
| Small-tube Teflon | Chemical resistance of tubes: no tube fouling. | Clean fluids, condensing, cross-exchange. | Low heat transfer coefficient. | 2.0-4.0 |
Source :
Ludwig, E. E., Applied Process Design for Chemical and Petrochemical Plants, 2nd Ed., Vol. 3, Gulf Publishing Co., 1983. GPSA Engineering Data Book, Gas Processors Suppliers Association, 10th Ed., 1987.
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