Spiral Pipe is available in 3-inch to 36-inch diameter in five foot lengths. It is considerably stronger than longitudinal pipe of the equivalent gauge. All 22 gauge Spiral Pipe measures 1/16″ less than the noted diameter on the inside (I.D.). Example 6″ diameter is 5-15/16″ I.D.
A ventilation Spiral Duct is the basic element of the ventilation system. Ventilation ducts are passages used to transport air – supply fresh outside air and remove stale indoor air. Ventilation ductwork can be divided according to its shape, namely, circular, rectangular and oval (a compromise between rectangular and round ventilation ducts).Circular Duct Series and Rectangular Ducts Series are the most common.
It can be also distinguished according to the material from which it’s made, e.g. rigid spiral pipe is usually made of galvanized steel sheet; flexible ducts often made of aluminium, polyester foil, etc. By far the most popular ductwork types used for both residential and industrial ventilation systems are rigid spiral ducting and Rectangular Duct.
1, the use of raw materials are produced by the steel galvanized steel plate;
2, high strength, small resistance, good sealing performance, beautiful appearance, simple installation, long service life;
3, the inner and outer walls are smooth, the air duct resistance is small, the air supply and exhaust does not produce secondary noise, reduce energy consumption, save operating costs;
4, can be cut on site , can drill, can open holes, simple installation, labor saving, time saving, shorten the construction period;
5, Galvanized spiral air duct does not need maintenance after completion of installation, reducing maintenance costs.
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