ABSTRACT
There are, however, many applications in which circular pressure containers or conduits cannot be used for various reasons. For example, the inlet nozzles on cyclones are usually of rectangular shape, as are the wood-chip chutes on pulp digesters; the headers on steam boilers are normally square; and the inlet and outlet headers of air-cooled heat exchangers are rectangular. For such noncir-
cular cross sections, flanges are often required, be it for access or for connection to other equipment.
