Feature
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A rectangular duct section on the manufacturing line .
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A square duct section including insulation to manage condensation challenges .
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A square double-insulated duct example . be designed to use various insulation or sound absorbing materials such as foams , boards , fibre or rubber .
DUCTING MATERIAL OPTIONS Today ’ s market sees various options available to clients and the choice of selection is reliant on several considerations above the requirements of simply managing air movement from one area to the next . Specific applications may be better suited to the use of a particular material type , or even a section of the dispersion system could make use of any type .
In a corrosive environment as an example , the use of certain steel or fabric would not be suitable and so as you would see in certain applications , the use of stainless steel or copper required as the appropriate material .
Galvanised steel This material is the traditional standard and most common material used in fabricating ductwork for HVAC systems . The specifications for galvanised steel sheet ducts are , for the most part , guided by the US Sheet Metal and Air Conditioning Contractors ' National Association ( SMACNA ) standards as well as the local South African National Standard : SANS 1238 : Airconditioning ductwork . Thickness of material as well as required supports are found in these documents .
Aluminium This material is widely used in clean room applications . These are also preferred systems for moisture laden air , special exhaust systems and decorative duct systems .
Stainless steel Generally used in duct systems for kitchen exhaust , moisture laden air , and fume / chemical exhaust .
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Painted steel ducting to meet client specifications in an office building .
Mild / black steel Widely used in applications involving flues , stacks , hoods and other high temperature and special coating requirements for industrial or processing use .
Copper Although vary rare in South Africa , this material would mainly be used when certain chemicals exist in air that need to be extracted that would otherwise result in unfavourable reactions with other material types .
Plastic / foam board A relatively new product in the local region and typically
sandwiched between an aluminium layer , this material is suitable for certain exhaust systems for chemicals and underground duct systems . Its advantages include resistance to corrosion , the
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