Advantages of using pultrusion
Pultrusion has a number of benefits over other composite processing systems. Some of the lowest cost, highest quality composite profiles are created by this process. This is because it is automated and has very little manual interface.
A manufacturer can be assured the 1st ten-meters of pultrusion will have the same quality and consistency as the 100th ten-meters of pultrusion. Human interface is eliminated, as required in most other processes, such as molding and hand-lay-up. Quality is not a function of motivation of factory technicians.
Another distinct advantage of the pultrusion process is cost. It is not unusual to find 80-90% of the cost of pultrusion profiles are the raw material costs. The amortized machine costs and the labor to run pultrusion machines is a small portion of the total factory costs. This has been a primary driver for pultrusion being one of the fastest growing and accepted manufacturing processes in the composites industry.
Pultrusion Advantages:
-Increased Strength (fiber processed under tension)
-High Fiber Content
-Highly Automated
-Consistent Quality
-High Production
-Low Labor Required
-Low Cost
FRP pultruded products are often stronger then a similar product manufactured by hand-lay up, vacuum bag infusion, and other composite processing methods. During the pultrusion process, the many fiber bundles are pulled downstream using hydraulic or caterpillar grippers. Due to this pulling, the fiber filaments are in tension when curing in the heated die.
When in tension, the fibers have higher strength values and are better aligned allowing good compaction, with more fibers fitting into a given volume. Fiber density is extremely high, as all excess resin is squeezed out before entering the die. Standard pultrusions can have fiber content of 50% by volume, 70% by weight, creating an extremely strong FRP composite.