Question and Answer about pultrusion

time:2020-6-8
GRP profiles are fully recycleable. There are recycling concepts for particle and energy usage available. A real advantage is the fact that no halogen or heavy metal is included which does not require special treatment.
GRP profiles may be glued. Typically single stage or multi stage glues will be used.
GRP profiles can be bolted with metallic or non-metallic bolts
Polyesters (UP) based GRP profiles are available without restrictions in colouring. Transparent colouring is generally not available.
GRP profiles are not meltable. They offer a high temperature resistance.
GRP profiles are containing – beneath the corresponding resin (thermoset or thermoplastic)- glass fibres, carbon fibres or other fibres. They can contain flame retardants (e.g. ATH), UV stabilizers and special fillers.
GRP profiles in direct comparison to thermoplastics are only showing very little creepage (cold flow) which is why the material is extremely well positioned for engineering appliances.
GRP profiles are very resistant against many organic and anorganic solvents. The chemical resistance depends an the matrix resin
There are special GRP profiles available to metal- plating and other coatings.
Thermoset matrices form opposite to thermoplastic matrices 3-dimensional network during moulding. This is the reason for their excellent temperature stability and very high thermo-mechanical properties.
GRP profiles do neither contain heavy metals nor halogens
No, not within the same part.
No, not within the same part.
Shrinkholes or recesses do not appear, if processing is done correctly.
GRP profiles usually do show very little shrinkage and post-shrinkage. Depending on the used fillers and resins you may experience shrinkages from zero to less than one per cent .
GRP profiles may be laser-marked.Furthermore you may code the product by ink-jet printing or chip technology (Laser or Needles).
See the chapter “What is pultrusion?“ at this web site
Yes, by the following methods: Grinding Drilling Turning Milling Sawing Water jet cutting Laser Blasting
Not during the manufacturing process
There are special screws available which allow direct screwing even into GRP profiles. The design of the screw holes has to be precisely adapted to the type of material. In particular the very little cold-flow of GRP profiles is giving high preference on these materials for direct screwing. These screw-fit is not designed for reversible usage.
See the chapter “moulds” at this website (“What is pultrusion”)
from 10 grs. up to serveral kilograms.
Usually tapers of 1-2 degrees are sufficient.
Mold-Flow-Simulation is used already. It is based on 3-dimensional layout and allows calculation of network-creation.
There is no need for deflashing
short time up to 250 ° C (depending on the matrix resin) long term ~ 120 ° C These data have to be checked and confirmed by application and cannot be taken as a general condition.
Cleaning with water and cleaning inhibits Solvents (to be checked and confirmed before usage)
Usually any kind of chipping does cut the fibres completely. If any, the brush-building effect of fibres is much less than on thermoplastics.
For standardized methods see chapter „standardisation“ at this website (“What is pultrusion”)