The rules of ASME Section VIII constitute construction requirements for pressure vessels. Division 2 of ASME Section VIII delineates alternative rules of construction to Division 1 requirements. However, there are some differences between the scopes of the two divisions. Recently added Division 3 provides Alternative Rules for Construction of High-Pressure Vessels.
The rules of ASME Section VIII apply to flanges, bolts, closures, and pressure- relieving devices of a piping system when and where required by the code governing the construction of the piping. For example, ASME B31.1 requires that the safety and relief valves on nonboiler external piping, except for reheat safety valves, shall be in accordance with the requirements of ASME Section VIII, Division 1, UG- 126 through UG-133.
Effective Edition, Addenda, and Code Cases
Editions are effective on—and may be used on or after—the date of publication printed on the title page.
Addenda are effective on—and may be used on or after—the date of issue. Addenda and revisions become mandatory as minimum requirements six months after date of issuance, except for pressure vessels contracted for prior to the end of the six-month period.
Code cases may be used beginning with the date of their approval by the ASME. Use of revisions and addenda and code cases that are less restrictive than former requirements must not be made without assurance that they have been accepted by the proper authorities in the jurisdiction where the pressure vessel is to be installed. #Little_PEng