Most extruded products are produced using single screw extrusion. Parts such as window frames, house siding, and weather stripping, which have a constant profile, are generally produced by means of single screw extrusion. Due to such factors as the melt swelling as it exits the die, the die design for an extruder is critical. Great complexity is sometimes needed with an extrusion die in order to gain the correct profile. The two largest industries for extrusion are pipe and tubing extrusion and film and sheet extrusion. There are many other industries that use extrusion to create their products though. Fiber extrusion, for clothing, coating extrusion, and blown film extrusion are just a few of the others. -------------------------------- Ningbo Jinyi Precision Machinery Co., Ltd. (since 1992) 158 Qiancheng Road, Zhenhai District, Ningbo 315207, China Email: info@jinyiscrew.com www.jinyi-machinery.com www.jinyi-precision.com