Cylindrical shell fabrication method

Cylindrical shell fabrication method used by Combustion Engineering (C-E)... 

Evaporator Costs. With so much variation in evaporator construction, materials, and accessories, manufacturers are reluctant to give standard cost figures. The most reliable method seems to be to estimate the unit cost as cylindrical shells, plates, heads, tubes, fittings, etc., based on the weight of material and the unit material and labor costs. This is the method generally used by fabricators. A published set of cost curves for preconstruction cost estimating is given in Fig. 6-12. 

One of the most common methods of supporting vertical pressure vessels is by means of a rolled cylindrical or conical shell called a skirt. The skirt can be either lap-, fillet-, or butt-welded directly to the vessel. This method of support is attractive from the designer s standpoint because it minimizes the local stresses at the point of attachment, and the direct load is uniformly distributed over the entire circumference. The use of conical skirts is more expensive from a fabrication standpoint, and unnecessary for most design situations. 

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