The ASME Boiler and Pressure Vessel Code, Section VIII, Pressure Vessels, is published in three parts, Division 1; Division 2, Alternative Rules; and Division 3, Alternative Rules for High Pressure Vessels. In comparison to Division 1, Division 2 vessels require more complex design procedures as well as more restrictive requirements on design, materials, and nondestructive examinations; however, higher design stress values are permitted in Division 2, and it is possible to design pressure vessels with a safety factor of 3. [At the present time Division 2 is being extensively rewritten, and it might take another year or more to finish. For information on the new volume see the paper An Overview of the New ASME Section VIII, Division 2 Pressure Vessel Code by D. Osage (published in Pressure Vessels and Piping Codes and Standards 2003, PVP Vol. 453). This chapter discusses the current version.] It should be noted that in this chapter, all Code paragraph references are to specific parts of Division 2. The alternative rules apply only to vessels installed in a fixed (stationary) location (see Code Par. AG-100).

In Division 2 vessels, the requirements of Section VIII have been upgraded. A very detailed stress analysis of the vessel will be required. There are many restrictions in the choice of materials, more exacting designs, and stress analyses. Closer inspection of the required fabrication details, material inspection, welding procedures and welding, and more nondestructive examinations will be necessary since design stresses are larger than those permitted in...