Shell Sizes

Shell Sizes Heat-exchanger shells are generally made from standard-wall steel pipe in sizes up to 305-mm (12-in) diameter from 9.5-mm (ys-in) wall pipe in sizes from 356 to 610 mm (14 to 24 in) and from steel plate rolled at discrete intervals in larger sizes. Clearances between the outer tube limit and the shell are discussed elsewhere in connection with the different types of construc tion. 

Minimum coil length Minimum fire tube area Shell size... 

Figure 10-4A(2). Multitube hairpin fintube heat exchangers. The individual shell modules can be arranged into several configurations to suit the process parallel and/or series flow arrangements. The shell size range is 3-16 in. (Used by permission Brown Fintube Co., A Koch Engineering Co., Bui. B-30-1.)...

The foregoing results demonstrate that the thickness of the capsule wall can be controlled at the nanometer level by varying the number of deposition cycles, while the shell size and shape are predetermined by the dimensions of the templating colloid employed. This approach has recently been used to produce hollow iron oxide, magnetic, and heterocomposite capsules [108], The fabrication of these and related capsules is expected to open up new areas of applications, particularly since the technology of self-assembly and colloidal templating allows unprecedented control over the geometry, size, diameter, wall thickness, and composition of the hollow capsules. This provides a means to tailor then-properties to meet the criteria of certain applications. 

Tube count tables which give an estimate of the number of tubes that can be accommodated in standard shell sizes, for commonly used tube sizes, pitches and number of passes, can be found in several books Kern (1950), Ludwig (2001), Perry et al. (1997), and Saunders (1988). 

Shell size could be read from standard tube count tables. 

This approach provides a preliminary specification for the heat exchanger. The actual heat exchanger will be restricted to standard tube lengths, tube layout and shell size. The preliminary design would then be adjusted up to meet standard size and layout specifications. 

Capsule shell sizes are generally standardized with Lnite volumes [12,13] available for dispensing the API or powder blend. The capsule size selection would depend on the dose and the bulk density of the NCE. Historically, if the doses were within a reasonable range, it was feasible to dispense API directly into the capsule body utilizing manual, semiautomatic, or automatic high-speed encapsulators available for manufacturing. 

The former is closer to a standard shell size and 166 x 19 mm tubes on 25.4 mm square pitch with two tube side passes can be fitted within a 438 mm i.d. shell. In this event, the water velocity would be slightly less than 1 m/s in fact (1 x 146/166) = 0.88 m/s, though this would not affect the overall coefficient to any significant extent. 

HONISCH, B. Hemming, N. G. 2004. Ground-tmthing the boron isotope paleo-/)H proxy in planktonic foraminifera shells partial dissolution and shell size effects. Paleoceanography, 19 PA4010, doi 10.1029/2004PA001026. 

Eldereield, H., Vautravers, M. Cooper, M. 2002. The relationship between shell size and Mg/Ca, Sr/Ca, 8 0 and 8 C of species in planktonic foraminifera. Geochemistry, Geophysics, Geosystems, 3, 10.1029/2001GC000194. 

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