Gas Lines in the Czech Republic on the Safe Side with HOBAS GRP
A special medium requires special treatment. Gas for instance requires special caution and safety measures. Requirements which are perfectly fulfilled by HOBAS GRP Protective Pipe Systems: They ensure tightness; have a high load capacity and offer a long service life. And, as projects in Poland and in the Czech Republic show, they can be installed by both trenchless and open trench methods.
Brno, Czech Republic. In the context of the expansion of the Avion Shopping Park in Brno-Dolní Heršpice it became necessary to relocate a steel high pressure gas main, DN 500 in diameter. During its inspection the operator Jihomoravská plynárenská a.s. had discovered signs of corrosion probably due to the installation and surrounding wet soil. This was no surprise as the pipeline is situated nearby the Svratka River so that fluctuations in groundwater level slowly but surely cause the steel to corrode. Playing safe, the operator decided to protect the gas main with a pipeline that is watertight and highly corrosion resistant. The possibility to extend the parking and storage surfaces of the shopping center some time in future had to be kept open as Brno’s first shopping park has been growing ever since its establishment in 1998. This meant the protective pipes would also need to provide appropriate load capacity. Searching for a suitable material that would fulfill these two main requirements, the client found the optimal solution in HOBAS GRP Pipe Systems.
The new steel pipes were welded one after the other and consequently pulled into the prepared HOBAS Protective Pipeline. RACI plastic spacers kept the gas carrier pipe perfectly aligned within the GRP containment system. Thanks to the smooth inside surface of the HOBAS Pipe this could be done swiftly and without complications. Pipe sections of 25-m-length were this way prepared at a time which were then, one after the other, lowered into the pipe trench with the help of nothing but the constructor’s excavator – thanks to the comparably light-weight GRP material. Here the inner steel gas main was welded to the already installed part and the GRP pipe was simply slid into position and pushed into the coupling that is delivered readily fixed to one pipe end. The HOBAS System’s FWC couplings with their elastomer rubber gasket are indeed a further plus as they not only facilitate the assembly thanks to simple push-to-fit mounting but also accommodate angular deflection while remaining tight – a perfect feature that helps omit costly fittings on gently curved routes. Once a pipe section had been completed the ends were capped with a rubber seal to keep the line clean.
A total 156 meters of HOBAS Protective Pipe DN 700, PN 1, SN 10000 were this way successfully installed during September 2011 and ensure trouble free, safe service for the next decades.