Spiral Lockseam Ducting

Inskip Spiral Ductwork is manufactured in Adelaide, South Australia and is available in diameters from 75mm up to 1400mm and in wall thicknesses from 0.55mm to 1.6mm. Round ductwork takes advantage of the strongest natural shape for withstanding both positive and negative pressures. In addition, the helical 4 ply lockseam adds rigidity to the duct-work, resulting in a strength equal to conventional ductwork two gauges heavier.


Spiral ductwork features a number of advantages over conventional ductwork:

High strength means fewer hangers
Long 6m lengths means fewer joints

Ease of installation


Inskip Spiral Lockseam Ductwork is available in galvanised steel and grade 304 stainless steel.


Inskip spiral ductwork is available in a range of sizes, as shown in the sizing chart. All Inskip spiral ductwork comes in 6m lengths as standard. All available sizes comply with AS42542002 Table 2.4 for operating pressures up to 2500Pa positive pressure.


All Inskip spiral ductwork features a helical 4 ply lockseam joint:
Inskip Lockseam Joint
This manufacturing technique results in a smoother internal bore, for low turbulence flow. Applications Inskip spiral ductwork is suitable for a variety of applications including; heating and ventilation, air conditioning, dust and fume control, bulk material handling, rubbish chutes, and concrete formwork.


Inskip Dust and Fume also fabricates a wide variety of fittings to suit spiral ductwork including; joiners, bends, branches, cones, flanges, valves, flues, weather cowls, junctions and more.

Inskip Spiral Lockseam ducting

Click to see Chart PDF

Spiral Lockseam Ducting Sizing Chart