Shell plate thickness

Note If Wj exceeds the shell plate thickness, then a re-pad must be used. 

The minimum acceptable shell plate thickness for tanks was calculated according to API Standard 653 [1]. 

The thicknesses of the shell plates of the gasoline AST measured after 55 years service, the calculated minimum acceptable shell plate thickness, and the corrosion rates are presented in Figures 7.1 and 7.2 (the numbers of the... 

An early study of strain mea-surernents on elliptical dished heads was reported by E, Holm (1I.>) a translation of which ap )eared in Mechanical EngineeritKj (lit . In this study an elliptical head having a 1.97 to l.Ot) major-to-minor-axis ratio and having an outside diameter of. 11.7 in., a heaf 8, Iti, and 2 t atm. 

Item 2. Shell Plate Thicknesses for Typical Sizes of Tanks with 72-in. Butt-welded Courses... 

Item 2. Shell Nozzle Dimensions in Inches as a Function of Shell Plate Thickness, Recommended by API Standard... 

The openings (discharge ports) in the kiln shell at the planetary cooling tube inlets mechanically weaken it. This must be compensated by local increase in shell plate thickness (upto 60mm in kilns of 3.8—4.6 m diameter, at least 80 and ranging up to 100mm for kilns of 4.6—5.6m diameter). See Fig.37. 

Figure 4.S. I (a) Some typical examples of different types of boiler defects. (Courtesy Milton and Leach ).(b) Examples of surface and buried defects in boiler and plates.T = endplate/tube plate thickness (mm) t = furnace or shell plate thickness (mm) o = depth of surface defect ...

Increase shaft diameter and decrease end plate. thickness Increases / and decreases t in eqn. 28.10. Would need 250 mm diameter shaft + 1 5 mm thick end plate very heavy and expensive. Would still need to check plate-shell weld. 

Corrosion allowance Tube diameters Square pitch cleaning lane Mm. shell thickness Transverse baffle and support plate thickness Min. thickness longitudinal battles... 

Design procedures for tube-plates are given in BS PD 5500, and in the TEMA heat exchanger standards (see Chapter 12). The tube-plate must be thick enough to resist the bending and shear stresses caused by the pressure load and any differential expansion of the shell and tubes. The minimum plate thickness to resist bending can be estimated using an equation of similar form to that for plate end closures (Section 13.5.3). 

Make recommendations for the mechanical design of the C02 removal absorber, estimating the shell and end-plate thickness and showing, by means of sketches suitable for submission to a design office, how ... 

The shell of a rotary dryer is usually constructed by welding rolled plate, thick enough for the transmission of the torque required to cause rotation, and to support its own weight and the weight of material in the dryer. The shell is usually supported on large tyres which run on wide rollers, as shown in Figure 16.10, and although mild steel is the usual material of construction, alloy steels are used, and if necessary the shell may be coated with a plastics material to avoid contamination of the product. 

B) Tubesheets hold the tubes in place and provide the barrier between the tube-side fluid in the tube-side channels or head and the shell-side fluid. The tubesheet is a circular plate, thick enough to withstand any pressure difference between the two fluids and suitably drilled to accept the tubes. The tubesheets may be welded to the shell... 

Generally, if the geometry of the shell is of a size that can be shop fabricated resulting in a minimum number of segments being shipped to its erection site, steei stacks will be the least expensive. This, of course, is a very general statement in that the plate thickness and unit price of material will be a much greater consideration for taller stacks (150 ft. and above) and those which are not constructed of plain carbon steel. 

The ASME BPV Code Sec. VIII D.l Part UW describes the requirements for pressure vessels fabricated by welding. Limiting plate thicknesses are specified for each type of weld with the exception of double-welded butt joints. Requirements for radiographic examination of welds are also specified. Section UW-13 of the code specifies the types of welds that can be used to attach heads and tube sheets to shells. Section UW-16 gives rules for attachment of nozzles to vessels. 

The minimum tensile and yield strengths of the shell plate material and the design stresses used to determine the plate thicknesses for the described design methods are summarized in Table 4-19. 

Table 4-19. Minimum Tensile and Yield Strengths of Shell Plate Material and Design Stresses Used to Determine Plate Thickness...

The thickness of shell plate required to resist the bending moment only, is therefore... 

The shell plates were ordered to size with guaranteed chemistry and tensile properties (to Section II and additional C-E requirements), but there was no guarantee on toughness. The plates were ordered with a thickness that would assure minimum wall thickness after fabrication, with the required length in the circumferential direction, and with an additional approximately 60 cm in length (in the axial direction) to provide for the necessary test material. Upon receipt by C-E, the plates were UT inspected for integrity (laminations, slag inclusions, etc.). 

Typically, die designer will check the required shell thickness at elevations where a seam is required. Actual plate thicknesses used will include a thinning allowance to accommodate thinning which occurs in the pressing of die plates. The plates do not get lighter. The actual plate... 

The most common defect found in these types of vessels is thinning or pitting of the shell plates due to corrosion on the inner surface and this is normally countered by reducing the safe working pressure, which is calculated from plate thicknesses and other data ascertained at the examination. The safe working pressure must be specified in the report. 

Hg. t.7. Examine of welded jeMs. (Nofe- the two types of lop welds diown moy be used only f[Pg.7]

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