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Product Description


Spiro-loc is a light weight sheet metal tubing, which is machine made in a spiral form from metal strip coil stock. Forming dies are held for common sizes between 100 mm and 1500 mm diameter. Special dies can be produced for larger or non standard sizes.

The four ply lock seam adds sufficient strength for the circular shape to be rigidly maintained up to 600 diameter in 0.95 mm material, or 500 diameter in lighter gauge. Additional rigidity and crushing strength can be achieved by the incorporation of one or two external swages. Common applications include ducting for heating, ventilating and air conditioning, void forming in concrete, irrigation pipe and rubbish shutes on high rise buildings.

Selection of Wall Thickness and Girth Joints The following table presents data which is acceptable under Australian Standard AS 4254-2002 ‘Ductwork for air-handling systems in buildings’. For more complete information refer to AS 4254

Product Specification

Series Spiro-Loc Lightweight plain galvanised steel construction, spirally wound ductwork, with a four ply lockseam joint, suitable for HVAC applications, concrete void forming, irrigation pipe and rubbish shutes. Additional single or double swages can be incorporated to improve ridgidity and crushable strength.

Complies with AS4254: 2002, AS1530.3 and UL181, where applicable.

All shall be Series Spiro-Loc as manufactured by Holyoake.

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