Water tube boiler with upper and lower reservoir - each including manhole so that workman can apply internal weld bead to shell joint

摘要

The water tube boiler has upper and lower horizontal reservoirs coupled by a tube bundle defining a combustion chamber and a heat exchange surface. Each reservoir has an oblong or oval cross-section, the upper and lower horizontal plates being joined by welded vertical braces. Each reservoir is defined by two shells, the edges being folded to form quarter-circle sections. The shells are welded together so that the edges define semi-circles. Each reservoir pref. includes a manhole so that a workman can internally weld the junction between the shells.