Products details

Pultruded Grating
The pultruded grating product is a mostly mechanized process. Reinforcement of different shapes such as: strand, mat and veil are pulled through a liquid resin bath   and a heated die where the bar is shaped and the resin is cured
These pultruded bars can be cut into requested lengths. The bars are then drilled on the sides to accept the crossbars. The drilled bars are spaced. The final step is to seal the entire crossbars and holes with corrosion resistant epoxy resin.
The pultruded grating provides increased load capacity with moderate levels of corrosion resistance. The components (bearing bars and cross bars) are pulled by machine to have a higher reinforcement content. Its superior load capacity is a result of the higher reinforcement to resin ratio. The pultrusion process is automated and produces a consistent, high quality finished product. Assembled from bars, the pultruded grating can offer a wide variety of panel sizes and substantially reduce "scrap loss".

  THE PULTRUSION PROCESS
Pultrusion is a manufacturing process for producing continuous lengths of reinforced polymer structural shapes with constant cross-sections. Raw materials are a liquid resin mixture (containing resin, fillers and specialized additives) and flexible textile reinforcing fibers. 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 mat and doffs of roving. As the reinforcements are saturated with the resin mixture ("wet-out") in the resin bath and pulled through the die, the gelatin 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. On exiting the resin bath, the composite is in a flat sheet form. The performer is an array of tooling which squeezes away excess resin as the product is moving forward and gently shapes the materials prior to entering the forming and curing die. In the forming and curing die, the thermosetting reaction is heat activated (energy is primarily supplied electrically) and the composite is cured (hardened). On exiting the die, it is necessary to cool the hot part before it is gripped by the pull blocks (made of durable urethane foam) to prevent cracking and/or deformation by the pull blocks. Strong well uses two distinct pulling systems, one that is a caterpillar counter-rotating type and the other a hand-over- hand reciprocating type to pull the cured profile to the saw for cutting to length.