The design of extrusion dies depends on the experience of the designer. After the die has been manufactured, it is tested during an extrusion process and machined several times until it works properly. The die is designed by a trial and error method which is expensive interms of time consumption and the amount of scrap. Research is going on to replace the trial pressing with finite element simu...

one of the most important parts of power transmission in automotives is c.v. joint, which consists of four components where exterior bowl is one of them. due to its complexity, and importance in automobile and existence of high stresses, forging process is the only cost effective method of production. hence, the best method of production of this part is forging process. the exterior part of c.v...

This paper describes the instrumentation and computer interface design for an extrusion tool to monitor certain process parameters during forward cold extrusion. A load sensing component, i.e. load cell was designed and manufactured to measure the extrusion forces. The load cell consisted of an individual component within a die set mounted in a 200-tonne hydraulic press, designed to study forwa...

LDPE remains the classic material of choice for many Extrusion Coating Applications, due to excellent processing and end-use performance reasons. High shear extrusion screws are desirable, actually promoting oxidation of the melt for improved adhesion to substrates. T-shaped flat die technology, with internal deckling, has emerged as the premium technology to handle monolayer and multilayer ext...

The dimensioning of injection heads for the extrusion of rubber profiles is exclusively based on empiric knowledge of the non-linear flow behavior of elastomers. Thus, the design of injection heads is carried out with subject to the used rubber compound, whereas the geometry of the appropriate profile is achieved by empiric adaptation of the extrusion die. This was one of the motivations for a ...

Traditionally, the cold extrusion die is of flat-faced shape. The dead metal zone causes high shear friction resulting in short die life. To lengthen the die life, the geometry of the die can be optimised. In this paper, the die geometry which is a free form surface, is created based on the user selected die inlet and outlet profiles. Upper-bound theorem in plasticity and optimisation algorithm...

Influence of convective cooling at the extrudate’s free surfaces on its own swelling behaviour is examined numerically when viscous fluids of a Newtonian type are extruded. In circular die extrusion, increasing the surface heat transfer coefficient h increases extrudate’s thickness swell at low Nahme-Griffith number Na; at high Na, however, this trend tends to be reversed. With annular dies, a ...

Extrusion dies are usually regenerated several times (min 4 times). The phenomenon of extended life after each regenerative nitriding process has not been explained. In this work, the regeneration process of dies used in the extrusion of aluminium profiles has been presented. In the article, it was sought to explain the cause of increased die durability after the third or fourth nitriding. Also...

Plastic extrusion has been a challenging process for many manufacturers and researchers to produce products meeting requirements at the lowest cost. Faced with global competition in plastic-products industry, using the trial-anderror approach to determine the process parameters for plastic extrusion is no longer good enough. During production, quality characteristics may deviate due to drifting...