| 摘要 |
<p>The liquid- or gas-fired boiler has a sheet-metal water casing for a tubular iron casting. This has front and rear sealing portions, and contains a hearth, hot gas passages, and a plenum chamber. The inserted portion (1) comprises a sheet-steel tube (2), with an inner tube (3) of grey cast iron. The sheet-steel tube is joined at the ends (2') to the edges of the opening (4) in the front and rear walls (5, 6) of the boiler (7).</p> |
