The widespread use of large scale units for manufacturing blown film, blow-moulded articles, flat film, and extruded pipes necessitates troubleshooting on site. Experience shows that troubleshooting in these and many other areas of polymer extrusion can be achieved quickly by applying proven, practical calculation procedures. Starting from polymer rheology and thermodynamics, the book Diagnostics of Extrusion Processes shows how screw and die design are easily examined using simple formulas. Designed to be used on-site, with many examples taken from the shop floor, this valuable diagnostic tool helps to optimise screw and die geometry, leading to high quality products.