Pultrusion process manufacturing

Joshi S. The pultrusion process in polymer matrix composites. In Advani S, Hsiao K-T, editors. Manufacturing techniques for polymer matrix composites (PMCs). Cambridge (UK) Woodhead Publishing Limited 2012. 

The pultrusion process has a low labour requirement and it can manufacture large amounts of profile with high glass-to-resin ratio, using continuous roving at a competitive cost. 

Pultrusion—Process for the manufacture of composite profiles by pulling layers of fibrous materials, impregnated with a synthetic resin, through a heated die, thus forming the ultimate shape of the profile. Used for the manufacture of rods, tubes and structural shapes of constant cross-section. 

This is a variation of the pultrusion process for the manufacture of hollow tubes. The die used is similar to that used in conventional pultrusion but the mandrel which forms the... 

Consider as an example a tension member manufactured from uni directional E glass fibres and polyester resin by the pultrusion process. The design criteria are hsted below ... 

Determine the maximum axial design compressive force that can be safely applied to the glass FRP section shown in Figure 4.1. It is manufactured from E-glass random mat plus roving and polyester resin, by the pultrusion process. 

T Asai, T Ohara, T Tanaka, S Hashizume. Method of Manufacturing Continuous Fiber-Reinforced Thermoplastic Prepregs. U.S. Patent 5529652, June 25, 1996. J-M Charrier, PJ Bates, D Guillon, G Zanella. The Effect of Pin Shape on Spreading Roving Filaments for a Thermoplastic Pultrusion Process. 45th Annual Conference, Composites Institute, SPI, Washington DC, 1990, 18-A, pp 1-4. 

Sumerak, J. E. and Martin, J. D., Pultrusion process variables and their effect upon manufacturing capability , 39th Annual Conference, Composites Institute, SPI, 1984. 

Pultrusion is relatively an old process of manufacturing long FRP composites. Goldsworthy is believed to have pioneered the pultrusion process in the early 1950s. In those days the technique was mainly adopted to fabricate parts requiring uniaxial performance such as rods, poles, handles, etc. 

Kowsika and Mantena (1996) proposed a statistical test pattern in manufacturing unidirectional graphite-epoxy composite beams using pultrusion. The influences of significant variables of the pultrusion process together with their interactive effects on the dynamic mechanical properties were investigated. Mathematical models were subsequently derived to determine the optimal pultrusion process conditions for improved dynamic mechanical properties of the finished product. 

Thunhorst K, Goetz D, Hine A and Sedgwick P (2011), The effect of nanosilica matrix modification on the improvement of the pultrusion process and mechanical properties of pultruded epoxy carbon fiber composites . Composites 2011, Fort Lauderdale, FL, American Composites Manufacturers Association. 

The preceding short process description is based on the most basic—but also most common—pultrusion setup. There are several variations to the theme, however, and many details were intentionally left out. In the following, the process is described in some detail and different processing and machinery options are briefly discussed. The variety in machinery solutions reflect the fact that many, perhaps most, pultrusion machines used to be designed and built inhouse by the pultruder rather than by a dedicated machinery manufacturer. There... 

The important process-control parameters in pultrusion manufacturing are the pull speed, fibre volume fraction, viscosity, temperature settings for die heating zones, and the preform plate area ratio (compaction ratio). Key process variables include die pressure and temperature. 

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