Processing

Pultrusion

Pultrusion is a technique to produce glass fibre reinforced profiles. Dry glass fibre rovings are pulled through a resin bath in which they are impregnated with UP-resin. The impregnated fibres are pulled through a heated die in which the resin cures at temperatures of 110 – 160°C. The die has the shape of the profile to be produced. After curing in the die the cured profiles are cooled down and cut at the desired length.

Pultruded profiles have a high glass fibre content and consequently very high mechanical properties. This is a particular advantage in civil engineering applications like bridges and constructions for production installations. Compared to steel profiles GRP pultruded profiles show a much better corrosion resistance and electrical insulating properties.

With the pultrusion process virtually every desired profile can be manufactured.

A wide range of standard industrial profiles is available in the usual U-, I- and O-shapes, but with pultrusion very complicated profiles can also be made. These profiles find their use in a wide variety of end markets.

Early applications for pultruded profiles were the production of electrically insulating ladders and fishing rods. Nowadays, profiles are used e.g. in the transport sector, for infrastructural applications and in the chemical industry for walking grids.