Spiral heat exchangers consist of metal sheets rolled into a spiral, welded together in a special way. Sheets form a heat exchange surface and channels through which flows move. The distance between the sheets (channel height) can be from 6 to 20 mm. The width of the channel varies from 0.25 to 1.5 meters.
The main advantage of a spiral heat exchanger is its compactness, lower hydraulic resistance, which is present in shell-and-tube heat exchangers.
The main disadvantage is the work with relatively low pressures and the complexity in manufacturing. Spiral heat exchangers are collapsible and non-separable (welded). Basically, heat exchangers are made of stainless steel.