Pultrusion vs Extrusion: A Cross-Sectional Analysis
by Tencom Ltd.
When Tencom considers the manufacturing options available, the choice is always made with the customer in mind. Low-cost, low-weight, high strength and versatility are of paramount importance to our customers. Pultrusion is a technique that offers all these qualities and makes Tencom the top choice for customers with high-performance needs.
Similar to its sister-process, extrusion, pultrusion is the process of passing material through a die to create a uniform product of unchanging profile. Extrusion pushes material through a die whereas pultrusion, as the name suggests, pulls the material through.
Pultrusion utilizes composites that are reinforced with long strands of fiber, such as carbon, Kevlar or glass, and a resin. The pultruded materials are light-weight and very strong, benefiting structurally from an increased tensile strength thanks to the continuous length of reinforcing fibers.
Composite pultrusions are used for many applications such as leaf springs, guy wires, tool handles and even xylophone keys. Extrusion is common for aluminum and thermoplastics. Pultrusion, on the other hand, offers the advantageous material properties of composites.
These properties include corrosion resistance, low weight, ultra-fine fabrication tolerances as well as superb resistance to electrical conductivity, thermal range, and moisture absorption.
When placed side by side, how do they stack up? Continuous filament composite rods that are pultruded can be on the order of 3x the tensile strength of all tempers of extruded 6063 aluminum.
Because of the low density of fiberglass-polyester composite, about 1.9g/cc, customers will see a strength-weight ratio that is far superior to metallic products that are often as much as 5x heavier.
Lower in cost than injection molding and compression molding; stronger, lighter weight, and more versatile than extruded products; pultrusion offers a cost advantage that is tough to beat.
That is why Tencom made the switch years ago and continues to believe that the pultrusion process offers its customers the superior product they’re looking for.