What is a PULTRUSION..?

Pultrusion Principle

            
PULTRUSION:

There are so many process techniques to manufacture Composite FRP products. Among all Pultrusion is a manufacturing technique to producing FRP structural profiles. Pultrusion is a continuous Fiber Reinforced Plastic (FRP) process for the manufacture of products having a constant cross section, such as structural shapes, beams, channels, pipes, tubes, fishing rods, and shafts etc. Pultrusion produces profiles with extremely high fiber loading, thus pultruded products have high structural properties and process high strength to weight ratio.

The Fiberglass Pultrusion Process

Pultrusion is a manufacturing process for producing continuous lengths of FRP structural shapes. Raw materials include a liquid resin mixture (containing resin, fillers and specialized additives) and reinforcing fibers. As the name suggests, the process involves pulling these raw materials (rather than pushing as is the case in extrusion) through a heated steel forming die using a continuous pulling device. The reinforcement materials are in continuous forms such as rolls of fiberglass mat or doffs of fiberglass roving. As the reinforcements are saturated with the resin mixture (“wet-out”) in the resin impregnator and pulled through the die, the gelation (or hardening) of the resin is initiated by the heat from the die and a rigid, cured profile is formed that corresponds to the shape of the die.

While pultrusion machine design varies with part geometry, the basic pultrusion process concept is described in the following schematic.

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Pultrusion Process

Continuous fiberglass reinforcements, in the form of roving and glass mat, are fed from a creel to a resin impregnation station, to coat each fiber with a specially formulated polymer thermosetting resin mixture (wet out).

The coated fibers are assembled, by shaping guides into the preformer, which squeezes away excess resin, as the product is moving forward and gently shapes the materials prior to entering the forming and curing die, which forms the desired cross section.

Composite Pultrusion Product 

The product made from Pultrusion process has composed with reinforcements(fiberglass rovings and mats) and resin.

Fiberglass Pultusion: is an engineered tailored product that can vary with the pultruder’s ratio of glass to resins, the formula of additives to meet specific requirements.

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FRP Vs. Traditional Materials

What are Composites..?

Benefits of Composites.?

FRP Vs Traditional Materials

FRP vs. Steel

Steelmaking began thousands of years ago, while the first composites made from reinforced fibers only debuted in the last century. But older doesn’t mean better. While steel has its place, composites FRP (Fiber Reinforced Polymer)are an ideal material for many applications.

Fiber Reinforced Composites offer several advantages over steel. Steel has intrinsic design limitations, is heavy and costly to transport and is susceptible to corrosion, which leads to high maintenance costs. Consider these features:

• Composites are corrosion resistant – In outdoor applications, composites stand up to severe weather and wide temperature changes. Steel rusts easily unless it is painted or coated with zinc. And corrosion is expensive with Steel.But with FRP its NO.
• Composites are lighter than steel – A cubic meter of cast steel weighs approximately 7800 kg. Depending on the material formulation, composites can be up to 70 percent lighter, i.e of approximately 2000kg only.
• Composites are incredibly strong – They can be custom-tailored to add strength in critical areas, such as spots that may bend or wear out. With steel, if greater strength is needed in any area then more metal must be added, which in turn increases weight.
• Composites are nonconductive – By their very nature, metals like steel conduct electricity. Composites are superior insulators: They don’t respond to an electric field and resist the flow of an electric charge.
• Composites allow for parts consolidation – A single piece made of composites can replace an entire assembly of metal parts, streamlining the production process and reducing lifetime maintenance.