Hemispherical head weights

You might think that hemispherical head weights can be computed easily from the following formulation ... 

La = inside radius of hemispherical head or inside crown radius of torispherical head, in., see Table 4 Le = fictitious length of straight pipe with the equivalent resistance of a pipe fitting of same nominal diameter as pipe, ft M = molecular weight, lbm/lbmol... 

CALCULATE THE SHELL THICKNESS, WEIGHT AND HEAD THICKNESS FOR HEMISPHERICAL HEADS. 

In years past, the ellipsoidal dished head was so much more available than the hemispherical dished head that the hemispherical head was limited primarily to small-diameter vessels. But vessel closure manufacturers have increased the nimiber of dies stocked for hemispherical head production and these are now becoming more widely used. If it were not for the cost of forming, the engineer would usually choose the hemispherical closure for the top head of a tall vertical vessel since it has the least weight and the lowest discontinuity stresses and is therefore the strongest. 

Weight of (1) hemispherical head, based on inside diameter, LBS... 

Consider a 78-inch ID hemispherical head with a nominal 1-inch wall. Compute the weight of the head. 

Compute the weight of a hemispherical head with an ID of 132 inches and a minimum head thickness of 6 inches. 

The computer program PROG43 determines the vessel weight of the pressure vessel with hemispherical, elliptical, and torispherical heads. Table 4-7 gives input data and computer output for 2 ft 6 in.-diameter vessel. The output gives the shell and head thicknesses, the weights of the shell and head, and the total weight of the vessel with hemispherical, elliptical and torispherical heads. 

IN ADDITION, HEAD THICKNESS AND WEIGHT ARE CALCULATED FOR HEMISPHERICAL, ELLIPSOIDAL AND TORISPHERICAL HEADS. TOTAL VESSEL WEIGHT IS CALCULATED (SHELL AMD HEADS) EXCLUSIVE OF NOZZLES, ATTACHMENTS AND VESSEL INTERNALS. TKS SHELL THICKNESS, in,... 

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