Plastics extrusion is a manufacturing process suitable for continuous profiles such as floor skirtings, window frames, and pipes. In industrial applications, extrusion is a large-scale process, financially attractive only for mass products. This is due to the time consuming and costly regulation of the extrusion process and especially, the design of an extrusion die which relies on running-in e...

Deformation of the material during cyclic expansion extrusion (CEE) is investigated using upper-bound theorem. The analytical approximation of forming loads agrees very well with the FEM results for different amounts of chamber diameter, friction factor and also for lower die angles. However, the difference between analytical and numerical solution increases at higher die angles which are expla...

Co-extrasion involves extrasion of multiple layers at the same time. Functionally graded materials comprising various layers with different properties can be produced through co-extrusion. Rheological control is vital for successful co-extrusion of layered cement-based materials. The paste flow in the barrel and the die land in a ram extruder should be plug-like, while the paste should be shear...

A typical extrusion of low and medium strength aluminium alloys solid shapes is performed with flat pocket dies. The pocket allows realising the extrusion as “billet-to-billet” process, and also facilitates filling-up die channel deadlocks and thin-walled elements of profile [1]. In addition it serves as an instrument for shape geometry control. The scientific literature contains a variety of r...

BACKGROUND To maintain a protective barrier, epithelia extrude cells destined to die by contracting a band of actin and myosin. Although extrusion can remove cells triggered to die by apoptotic stimuli, to maintain constant cell numbers, epithelia extrude live cells, which later die by anoikis. Because transformed cells may override anoikis and survive after extrusion, the direction of extrusio...

The dimensioning of injection heads for the extrusion of rubber profiles is exclusively based on empiric knowledge of the non-linear viscoelastic flow behaviour of elastomers especially of the so-called die swell.Thus, the design of injection heads is carried out with subject to the used rubber blend, whereas the geometry of the appropriate profile is achieved by empiric adaptation of the extru...

In aluminum extrusion, a work-piece (billet) is pressed through a die with an opening that closely resembles the desired shape of a profile. By this process, long profiles with an enormous variety of cross-sections can be produced to serve different markets such as building, construction and transport industry. When the shape of a profile does not conform to the specifications defined by the cu...

Nowadays Aluminum extrusion die design is a critical task for improving productivity which involves with quality, time and cost. Case-Based Reasoning (CBR) method has been successfully applied to support the die design process in order to design a new die by tackling previous problems together with their solutions to match with a new similar problem. Such solutions are selected and modified to ...

Three-dimensional flow of a low-density polyethylene in a spiral die for blown-film extrusion is simulated. Effect of elongational viscosity on the flow in the spiral die is analyzed. Elongational viscosity is found to have significant effect on the velocity distribution at the die exit and on the pressure and temperature distributions in the die.