Investigation of the External High and Moderate Water Pressure Influence on the Properties of the Sealed Thermoplastic Assembly Parts

 

Jovan Radulović

Duško Knežević

 

In this paper the influence of the external high and moderate water pressure on the properties of the sealed thermoplastic assembly parts are described. The specimen made of the impact resistant polystyrene mark Styron 485, four sealing systems and indicator paper (placed inside the sealed parts) are used for the production of the mentioned assemblies. Specific white silicone mark Dow Corning, modified black silicone mark Permatex, encapsulating system mark Araldite consisting of a modified epoxy resin and amine hardener and the solution obtained by dissolving the polystyrene mark Styron 485 in toluene, are used. The produced assemblies were sink in the water at the depth of 4 m (high water pressure) and at the depth of 1 m (moderate water pressure) according to the SRPS EN 60068-2-17 standard. Based on the detailed inspection of the plastic parts in the assemblies and indicator paper, it was concluded that the water breakthrough did not happen and that all four applied systems prevented the water pass through the sealed assemblies. The tensile testing of the produced assemblies was done in order to establish a homogeneity of the used sealing systems in the mentioned assemblies. Based on the visual inspection it was concluded that white silicone (system 1), black silicone (system 2) and epoxy system (system 3) are homogenous in the produced joints, while at the joints with a polystyrene solution (system 4) a certain porosity is recorded.

Key words: plastic materials, construction elements, assembly, water pressure, sealants, assembly homogeneity.