Cross Section of Metal Bellows
This figure shows the cross section of one of the bellows sections of tubing. These are not bellows in the sense of fireplace bellows that you use to blow air onto a fire. Instead, they're metal tubes. They're called "bellows" because sections of them are corrugated in a way that reminds people of the corrugated sides of fireplace bellows.
If this picture were a cross section of a plain metal tube, it would just be 2 straight, parallel lines. In fact, the 2 ends of the diagram are straight, parallel lines. In between the ends, the lines become zig-zag, representing the corrugated sides of the bellows.
Return to Cross Section
Drawing of Metal Bellows
This drawing shows what the metal bellows look like. The figure just before this showed the bellows in cross section. As I explained in the description of the cross section, these are not bellows in the sense that you use fireplace bellows to blow air onto a fire. They're only called bellows because their corrugated shape resembles the corrugated sides of fireplace bellows.
The bellows are essentially a tube. But not quite a tube, because when we say "tube", we normally think of something that has straight sides, that is, something that has the same diameter from one end to the other. The bellows are a tube that has a large diameter at some places and a small diameter in between. In other words, the bellows look like a tube made of corrugated metal (with the corrugations running around the tube, not end to end.)
Return to Drawing