Design of Pressure Vessels

In federal water of the U.S. and in a few states, all pressure vessels must be designed and inspected in accordance with the ASME Code. In many states, however, there is no such requirement. It is possible to purchase non-code vessels in these states at a small savings in cost. Noncode vessels are normally designed to code requirements (although there is no certainty that this is true), but they are not inspected by a qualified code inspector nor are they necessarily inspected to the quality standards dictated by the code. For this reason, the use of non-code vessels should be discouraged to assure vessel integrity. 

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Pressure Vessel Filters. The several designs of pressure vessel filters all consist of pressure vessels housing a multitude of leaves or other elements which form the filtration surface and which are mounted either horizontally or vertically. With horizontal leaves most suitable where thorough washing is required, there is no danger of the cake falling off the cloth with vertical elements, a pressure drop must be maintained across the element to... 

Safety as it is reflected in factors of safety in design of pressure vessels, pressure testing of piping and vessels, etc. Use of A.P.I., A.S.M.E. and ASA Codes Code Stamps on equipment. 

Gases are stored at high pressures where this is a process requirement and to reduce the storage volume. For some gases the volume can be further reduced by liquefying the gas by pressure or refrigeration. Cylindrical and spherical vessels (Horton spheres) are used. The design of pressure vessels is discussed in Chapter 13. 

This chapter covers those aspects of the mechanical design of chemical plant that are of particular interest to chemical engineers. The main topic considered is the design of pressure vessels. The design of storage tanks, centrifuges and heat-exchanger tube sheets are also discussed briefly. 

The objective function or the constraint functions may be defined in terms of complicated interactions of the variables. A familiar case of interaction is the temperature and pressure dependence in the design of pressure vessels. For example, if the objective function is given as / = I5.5xxx2m, the interaction between xx and x2 precludes the determination of unique values of xx and x2. Many other more complicated and subtle interactions are common in engineering systems. The interaction prevents calculation of unique values of the variables at the optimum. 

Derailed design of pressure vessels, including design of internals (many having patented features) should lx the responsibility of the equipment supplier. 

The design of pressure vessels is governed by the task of minimising manufacturing costs while fulfilling all predefined requirements, which represent a set of design and construction criteria. 

Additionally, in the pressure range from 250 bar to 10,000 bar a great number of batch processes can be found. This means, that the design of pressure vessels for these applications has to deal with cyclic loading and fatigue, considering far more severe conditions than at low pressure service. 

The pressure vessel design codes and standards include lists of acceptable materials, in accordance with the appropriate material standards. The ASME BPV Code Sec. II Part D gives maximum allowable stresses as a function of temperature and maximum temperatures permitted under Sections I, III, VIII, and XII of the BPV code for ferrous and nonferrous metals. The design of pressure vessels using reinforced plastics is described in ASME BPV Code Sec. X. 

The design of pressure vessels must also take into consideration weld efficiency, number and size of openings, and also add additional thickness to allow for controlled corrosion over time and use. 

A. Mackenzie, E. W. Dalrymple, F. Schwartz, Design of Pressure Vessels for Confining Explosives, Tech. Memo. 1643, Picatinny Arsenal, Dover, N.J., 1965. 

J. F. Harvey, Theory and Design of Pressure Vessels, Van Nostrand Reinhold Co. Inc., New York, 1985. 

Stresses caused by external local loads are a major concern to designers of pressure vessels. The techniques for analyzing local stresses and the methods of handling these loadings to keep these stresses within prescribed limits has been the focus of much research. Various theories and techniques have been proposed and investigated by experimental testing to verify the accuracy of the solutions. 

Designers of pressure vessels and related equipment frequently have design information scattered among numerous books, periodicals, journals, and old notes. Then, when faced with a particular problem, they spend hours researching its solution only to discover the execution may have been rather simple. This book can eliminate those honrs of research by providing a step-by-step approach to the problems most fre-qiientlv encountered in the desigii of pressure vessels. 

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