Machinery, Construction Machinery Mixed, Description Spiral tubeformer ST80 has the largest diameter range from 80mm to 1600mm, and use the special steel tape molds, which can reduce the molds cost heavily. Also the automatic cutting system can easily set any length to cut and has the reliable performance. the most economic spiral duct machine. Features 1 Ranging from 80mm~1600mm 2 Most economy type 3 Low cost for maintance 4 Saw balde cutting, Industrial Machinery, Construction Machinery ...