How To Make The Fiberglass Pultrusion Products？

    Before buying FRP products in our store, you really need to understand the standard fiberglass pultrusion process so that you can better understand the product features and make a decision. For example, a batch of fiberglass flat strips.

Step 1: Warp the yarn on the yarn frame and thread the yarn (preparation stage)

Place hundreds of rolls of untwisted fiberglass roving on the creel, and following the order set by the computer, guide the yarns through the slitting plate and guide pins, accurately into the resin dipping tank.

Step 2: Resin impregnation (wetting stage)

The fiber bundle passes through an open or closed resin impregnation tank, which is filled with a prepared mixture of resin (including unsaturated polyester/epoxy resin, curing agent, release agent, and filler).

Step 3: Pre-shaping (Shape Guiding)

The resin-soaked fiber bundles go through a series of preforming guides. The holes in these guides gradually change from round to flat rectangular shapes, gathering the scattered fiber bundles and compacting them into the initial shape needed for flat strips, while also squeezing out excess resin and air bubbles.

Step 4: Hot Curing and Shaping (Key Step)

The pre-formed strips go into heated metal molds (usually 0.6 to 1.2 meters long). The mold has three heating zones (preheating, gel, and curing), with the temperature increasing from the inlet to the outlet (usually kept between 120°C and 180°C).

Step 5: Cooling and Traction (Power Output)

The high-temperature flat strips that have been solidified are pulled out of the mold and cooled through a water or air cooling system. Then, a hydraulic traction machine grips the strips and continuously pulls them out at a constant speed, usually 0.5 to 2 meters per minute.

Step 6: Fixed-length Cutting (Finished Material Cutting)

The traction machine feeds continuous flat strips into the cutting area. According to order requirements, a flying saw (the blade moves at the same speed as the product) is used for online cutting, avoiding the burrs or chipping that can happen with regular cutting when the product is moving.