Chimney stack hollow tubular sections - have inner and outer concentric tapering insulated tubes with stepped ends

摘要

The chimney stack section for building has inside and outside tubular walls with insulating material between them. The insulating material is efficiently held between these tubes which are firmly connected at ends. The trapped insulation improves insulation performance. The outer tube tapers very slightly towards one end. The inside tube (4) is expanded at the opposite end. Both inner and outer tubes are strong together. These tubes (4, 5) are connected at the inturned flange end (7) of the outside tube. At the expanded end of the inside tube the outside tube extends axially over this expanded section of inside tube. The outside tube extension overlaps the end of the adjacent tube and insulation assembly.