Teppfa is the European Plastic Pipe and Fittings Association, founded in 1991, and headquartered in Brussels, Belgium. Teppfa’s 13 multinational company members and 15 national associations across Europe represent 350 companies that manufacture plastic pipes and fittings. The association’s members have an annual production volume of three million tonnes, directly employing 40 000 people, with €12 billion combined annual sales. Its final products are subdivided into two application groups: aboveground systems for hot and cold-water supply, surface heating and cooling, and wastewater discharge; and below-ground pipe systems for sewers, stormwater management, and the distribution of drinking water, gas and telecommunications.
Teppfa – the European Plastic Pipe and Fittings Association – commissioned the Sewer Installation Time (SIT) project to compare the installation time of sewer systems.
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ithin two parallel prepared trenches, a plastic and a concrete sewer pipeline were installed simultaneously by independent contractors with experience in plastics and concrete installation, respectively.
Approach
Regarding the installation technique of the project, 90 m of pipe and two inspection chambers were installed in a 2 m deep trench, whereas 20 m were backfilled. The trench was properly prepared to secure the accurate and safe installation of the pipelines. Trench support systems were not necessary and therefore not included in the project. The installation of the pipe systems was performed in accordance with the applicable EN standards. Since the installation of a complete sewer system was impossible, an Environmental Product Declaration functional unit (FU) was used for the project. The decision was to install a nominal diameter (DN) 300 mm thermoplastics pipe system in the FU and a DN 300 mm concrete pipe system. The project was executed under the same site logistics (location, equipment, trench, weather, contractor and video shots), and was video and time recorded. The two videos were run in tandem to depict the difference in installation time between plastics and concrete sewers.
Conclusions
“The time for a plastic sewer system to be installed is 30% less than the time for
PIPES
What pipe has a quicker installation time? an alternative material to be installed. To demonstrate, contractors needed 21 minutes to install the first concrete chamber and pipe, and 16 minutes to install the first plastic chamber and pipe. For a total installation of 90 m including two chambers, the plastic system was installed 30% faster than the concrete one and, as a result, 1 hour 53 minutes was the time saved,” explains Zoran Davidovski. In addition, and with regard to the limitations for each product, the installation of concrete sewers depends on the excavator speed, and the installation of plastic sewers more or less depends on the man in the trench. The excavator is also used for lifting the concrete pipes (causing a bottleneck) and is not needed for plastics. Several other invaluable findings have emerged from the SIT project: •L ess site transport is needed for plastics’ installation thanks to long pipe lengths. •T he positioning in-between and of the last chamber/manhole is more accurate and easier to realise with a plastic system. • While installing plastics, the excavator was waiting for the man in the trench to finish levelling, bedding and adding lubricant; while installing concrete, the man in the trench had to wait for the excavator, which had to lift and support pipes, and was needed for the pipes’ jointing. • Lifting equipment is not needed to install plastic chambers, but it is essential in installing concrete manholes. • Plastics need sand-bedding, which can be time-consuming and difficult to
Zoran Davidovski, head: R&D and Sustainability at Pipelife International and chairman of the Teppfa Health, Safety and Environment Working Group
arrange; however, one can easily de-level the pipe by adding sand support on either side. •T he backfill activities and time for both pipe systems are identical. •A part from the speed and ease of installation, plastic systems have 75% fewer leaks than concrete ones, too. “The SIT project provides evidence of how plastic piping systems, which are available in various types and sizes, fulfil customers’ performance needs,” Davidovski concludes.
Plastics need sand-bedding, which can be time-consuming and difficult to arrange, but one can easily de-level the pipe by adding sand support on either side
J UL / A U G 2021
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