21 Section VIII—Division 1: Rules for Construction of Pressure Vessels Available to Purchase

Chapter 21 initially authored by Urey R. Miller for the previous first and second editions is revised by Thomas P. Pastor for the current third edition. This chapter covers Section VIII—Division 1, Rules for Construction of Pressure Vessels. The author discusses the historical background of this Section in relation to the construction and safe operation of boilers and pressure vessels. Section VIII Division 1 is written to cover a wide range of industrial and commercial pressure vessel applications. This Section is applicable to small compressed air receivers as well as to very large pressure vessels needed by the petrochemical and refining industry. Section VIII Division 1 is intended for the construction of new pressure vessels. Miller discusses the applicability of Code and Code jurisdictions, as well as situations of the inapplicability and exemptions from this Section.

This chapter provides an overview to each of the parts of Section VIII Division 1 Code. The commentary includes Subsection A—General Requirements for All Methods of Construction and Materials; Subsection B—Requirements Pertaining to Methods of Fabrication of Pressure Vessels; Subsection C—Requirements Pertaining to Classes of Material; Mandatory Appendices; Non-Mandatory Appendices; and Bibliography. The intent of the author is to provide a broad perspective for the reader to have better understanding of the Code's intent, and to point out, by example, some of the subtleties that may not be evident. It is not the objective of this Chapter to provide the reader with a detailed “how to” hand-book. The user of the equipment must define the requirements that are needed for a specific application. With the help of equations, tables, figures and examples Miller provides detailed commentary of Section VIII, Division 1. He comments about several pertinent Code Interpretations and Code Cases pertaining to this Section.

There have been a number of significant changes to Section VIII Division 1 since the First Edition of this Guidebook. The most significant is that the previously non-mandatory rules for tubesheets (Appendix AA) and flanged and flued expansion joints (Appendix CC) are now mandatory and are in Part UHX and Appendix 5 respectively. Also, a new mandatory appendix (Appendix 32) has been added to the Code to allow consideration of local thin spots in shells and heads, and Appendix 33 has been added to define the standard units to be used in Code equations. The 2nd Edition of the Guidebook was updated to cover the ongoing Code revisions (that affect shell-to-tubesheet joints, Appendix 26 expansion joints, and Appendix M.

The Third Edition of the Guidebook covers revisions to Section VIII, Division 1 from the 2004 Edition through the 2007 Edition. Included are detailed descriptions of several new Nonmandatory Appendices, including Appendix FF: “Guide for the Design and Operation of Quick-Actuating (Quick Opening) Closures, and Appendix GG: “Guidance for the Use of U. S. Customary and SI Units in the ASME Boiler and Pressure Vessel Code”. This Chapter also includes extensive updating of referenced figures and tables from the 2007 Edition of Section VIII, Division 1.