Plate and frame exchangers

Since plate-and-frame exchangers are made by comparatively few concerns, most process design information about them is proprietary but may be made available to serious enquirers. Friction factors and heat transfer coefficients vary with the plate spacing and the kinds of corrugations a few data are cited in HEDH (1983, 3.7.4-3.7.5). Pumping costs per unit of heat transfer are said to be lower than for shell-and-tube equipment. In stainless steel 

TABLE 8.10. Recommended Individual Heat Transfer Coefficient Correlations  

Between parallel plates of length L and separation distance s 

In concentric annuli with 4 inside, d0 outside, and hydraulic diameter 4, = d0 — 4. I, heat transfer at inside wall II, at outside wall III, at both walls at equal temperatures 

TABLE 8.10—(continued) Across a bank of n tubes deep  

In concentric annuli with d/ inside, outside, and hydraulic diameter - 4. I, heat 

Across one row of long tubes d = diameter, s = center-to-center distance, a = 

Banks of radial high-fin tubes e = (bare tube surface)/(total surface of finned tube) In line  

Plaic-and-frame exchangers are an arrangement of gasketed, pressed metal plates aligned on carrying bars and secured between two covers by comptession bolts. The pressed metal plates are corrugated in patterns to provide increased surface area, to direct the flow in specific directions, and to promote turbulence. The plates are gasketed such that each of the 

Shell Fixed Tube Outside Poched Floating Head U -Tube  

She Fixed Tube Steel Outside Packed othiD Head U - lube 

Shell I.D. Tixed Tube Sheet Outside Packed Fkxitina Head U - Tube Shell IJ). Fixed Tube She Outside Packed Fbatina Head U - Tube 

Because the plates are made of thin pressed metal, materials resistant to corrosive attack can be easily selected. Plates are standard and mass-produced,. Specific applications are dealt with by changing plate arrangements. Stainless steels, monel, titanium, aluminum bronze, and other exotic metals 

Gasket Material Max. Operating Temp., °F Compatible Fluids 

Nitrile 230 Mineral Oils, Most Aqueous Solutions, Aliphatic Hydrocarbons, Inorganics (at low concentrations and temperatures) 

EPDM (Ethylene Propylene Diene Monomer Rubbers) 320 Steam, High-temperature Aqueous Solutions, Inorganic Acids and Organic Acids or bases 

Viton 212 Mineral Oils, Aliphatic and Aromatic Hydrocarbons, Sulfur Carbon Carbons, Trichloroethylene, Perchliroethylene 

Footnotes (a) Gaskets are also available in other materials, such as hydrogenated nitrile, neoprene, butyl rubber, hypalon, silicon rubber to meet various application requirtnents. (b) Viton is a Du Pont Co. trademark for a series of fluoroelastorners based on the copolymer of vinylidene fluoride and hexafluoropropylene. 

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Plate-and-frame exchangers transfer heat by passing cooling fluids and process fluids between large corrugated panels. Crevices exist between closely spaced panels that stimulate localized attack. Plates... 

Compared with traditional plate-and-frame exchangers, this design relies on a more loosely corrugated chevron pattern, which provides exceptional resistance to clogging. The plates are designed with few, if any, contact points between adjacent plates to trap fibers or solids. Some styles of this exchanger use wide-gap plates on the process side and conventional chevron patterns on the coolant... 

Figure 3-13. Plate-and-frame exchanger. (Courtesy of Tranter, Inc.]...

Plate and frame exchangers (plate heat exchangers) - used for heating and cooling. 

Figure 10-7A. Typical one side of Plate for Plate and Frame Exchanger. (Used by permission Graham Manufacturing Company, Inc., Bui. PHE96-1.)...

Plate and frame exchangers are suited to high sanitation services, and are 25-50% cheaper in stainless construction than shell-and-tube units. 

A process design of a plate-and-frame exchanger is worked out by Ganapathy (1982, p. 368). 

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