Manual cleaning and rehabilitation | Spray Lining
The epoxy and polyurethane coatings are used to provide protection to the metal pipe against corrosion.
Epoxy & Polyurethane Coatings
Epoxy and polyurethane coatings are used to provide protection against metal corrosion pipes. It is a system suitable for pipes of all diameters and usually able to offer a certain structural capacity. If used inside wells and tunnels, they are used to increase the seal.
As with mortar coatings, epoxy and polyurethane coatings also require careful preliminary cleaning of the pipe with removal of deposits, roots, scale, rust and debris in general. Furthermore, so that the covering of the covering to the pipe is solid, the walls of the latter must be absolutely dry.
Epoxy and polyurethane coatings, such as those in mortar, are usually applied by spray to reduce corrosive problems and improve the flow characteristics inside the pipe. To obtain a certain degree of structural capacity and sealing, applications in thicker layers are required.
Epoxy and polyurethane coatings create an impermeable barrier between the piping in which they are inserted and the flow of water inside them, thus inhibiting the onset of rust.
In smaller pipes, they are sprayed in thin layers of 1-1.5 mm using a high speed nozzle. In most cases, the resin and the catalyst are fed through separate tubes and are only joined in the mixer located just behind the nozzle.
The thickness of the coating is controlled by the flow rate and the speed of the machine. Unlike mortar coatings, the sprayed resin does not require smoothing or leveling.
The epoxy spray coatings harden in about 16 hours, much faster than the cement mortar.
The polyurethane ones, on the other hand, take only 2 hours. The thickness of both these coatings is lower than those used for cement mortars. However, epoxy and polyurethane coatings are more expensive and require careful quality control both during their application and in the polymerization phase so as to always ensure that the final coat is free from defects.
Epoxy and polyurethane coatings are also used for rehabilitation and corrosion protection in tunnels, pipes, wells and water and purification plants in general and can be applied both manually and by spraying.
The application of thicker polyurethane coatings offers a certain degree of structural and sealing advantage.