The selection of technical solutions and the choice of materials in the construction of Cooling towers are guided by several factors, and principally according to the kind of water with which the plant is gonna operate. In addition to steel, another frequent choice is the fibreglass, offering a series of advantages that are clearly explained in this article.
Despite of a higher cost, due for example to the investments required in manufacturing equipments and dedicated moulds, fibreglass is the preferred choice of many manufacturers of open and closed circuit cooling towers for the realization of both components and structural profiles. The main quality of fibreglass is certainly the fact that, in constant presence of water, it does not oxides and is corrosion resistant, a main problem with chemically aggressive water, it is not affected by weather conditions and is therefore maintenance-free. Fibreglass in addition is lightweight compared to steel and metal sheets, and can be simply repaired in case of accidents returning to as new conditions.
The construction technique of the moulded components employs successive layering of glass fabric, called ‘mat’, which is then soaked in resin. Following the catalyzation, the resin and the mat layers are fused into one body, giving structural robustness and a uniform surface. A special orientation of the glass fibres can be engineered in order to better withstand and distribute static and dynamic loads.
Structural profiles are manufactured using a pultrusion (pull+extrusion) process with a dedicated die, employing a catalysed resin mixture blended with a continuous-filament fibreglass, ensuring mechanical and structural resistance.
The pieces are then coated with a UV-resistant gelcoat providing external protection, while the inside is waterproofed by applying a gelcoat with a paraffin additive aimed to prevents osmosis.