摘要 |
<p>A boiler has an outer wall of weldable material and an inner chamber including a high temperature heat exchanger which is connected by pipes passing through openings in the outer boiler wall for the supply and discharge of a heat exchange medium. Each pipe for the heat exchange medium is spaced from and passes through a sleeve-like jacket that is welded to the outer boiler wall and projects outwardly therefrom. A cooling gas is fed into the sleeve-like jacket to pass along an annular space between the jacket and the pipe. The cooling gas flows into an annular chamber between the outer boiler wall and the inner chamber. According to a second embodiment, concentric sleeves are provided in the annular space between the jacket and pipe to pass the cooling gas to and fro within this space.</p> |