Price Holyoake Rigid Steel Duct - SPIROLOC

SPIROLOC 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 75 mm and 1500 mm diameter. Maximum proven practical diameter is 4.5 metres.

The four ply lock seam adds sufficient strength for the circular shape to be rigidly maintained up to 600 diameter in 1.0 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, smoke and exhaust stacks, chip conveyors, void forming in concrete, irrigation pipe and rubbish shutes on high rise buildings.