| 摘要 |
The elongated-shape ancillary heating-surface block has a sheet-metal casing. It is fitted beside, over or under the associated firetube, or water tube industrial or ship's-boiler. The block contains several tube bundles, separately removable from the casing, for use as air preheater and/or economiser units. The bundles, all substantially the same length, may adjoin each other laterally and/or vertically. They are pref. arranged at least partially successively in the gas stream. A bundle functioning as a superheater unit may be added. The bundles are pref. made of assemblies of conventional straight-tubes. |
