The screw of an extruder is considered as the “heart” of the machine and can have a significant influence on the achievable product quality, the achievable maximum throughput and the efficiency of the production plant. There are different basic concepts of screw design, which have different advantages and disadvantages. In […]
Monthly Archives: January 2018
4 posts
Due to the poor thermal conductivity of thermoplastics, residual stresses (tensile and compressive residual stresses) are build up in the walls of the product during cooling processes after extrusion. Deformations and distortion of the products often result from the residual stresses, whereby the presence of the residual stresses becomes visible. […]
In addition to the width of a film and the profile tolerance, the flatness is considered as one of the most important quality criterions. Good flatness refers to film products with a high planarity, also a low tendency for sagging areas or bulges. The flatness of a film is an […]
In extrusion, plastic granulate is plasticized by converting mechanical energy into thermal energy. The mechanical energy required for this (torque and rotation of the screw) is generated with the aid of electric motors, i.e. from electrical energy. The additional heaters often only contribute a small part to the overall energy […]