Emerald Group Publishing Limited
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Large diameter corrosion-resistant PE pressure piping system
Article Type: Methods From: Anti-Corrosion Methods and Materials, Volume 58, Issue 6
Over the last decades polyethylene pipes have proven its outstanding properties for the transport of fluids and gases and are steadily replacing cast iron, ductile iron, asbestos cement and GRP in many applications. AGRU Kunststofftechnik GmbH is celebrating its 50th anniversary for processing PE pipes this year and is one of the leading companies in pipe extrusion and manufacturing of high-grade PE fittings.
To provide quality solutions for the increasing demand for large diameter pipelines, AGRU developed a complete system which includes extruded pipes, fittings and welding technology up to 2,200 mm in diameter and up to 150 mm in wall thickness.
Based on valid engineering standards all large diameter fittings have been designed and validated by FEM calculation as well as proven by creep rupture tests in order to provide most secure and economic fittings to the client.
In house production based on long-term experience enables to produce these high-quality products within reasonable time.
PE bends, tees, stub ends and reducers are available now from OD 20-2,200 mm, end caps up to OD 1,000 mm. Fabricated bends, tees and reduced tees can also be provided in full pressure rating (Figure 2).
A core benefit of AGRU’s extrusion line for large diameter pipes is that it was since the very beginning designed for mobile setup with optimized site assembly and transportation capability. The benefit for the client is that the production plant can be shipped to the construction site to produce the pipes directly where they are needed. This reduces significantly transportation and installation costs. Pipes can be extruded up to several 100 m in length depending on the site conditions. The risk of damaging the pipe during transport is eliminated and the carbon footprint for the construction of large diameter pipelines can heavily be decreased due to the on-site production.
To provide consistent production quality on site QC by implementation of a mobile laboratory is performed. Supervisor and newest state of the art welding equipment ensures quality installation of such large diameter piping systems.
The main application areas where large diameter pipes will be applied are sea water intake and outfall pipelines, e.g. for desalination plants. Collecting and distribution pipelines for transport of potable, salt and process water or sewage in industrial and municipal areas. Cooling and pressure pipes, e.g. in power plants, underground fire fighting mains and pipelines for irrigation are main areas where the AGRU large diameter PE piping system proves their advantage in performance and costs.
PE has various benefits compared to other materials. The flexibility of PE allows easy bending, which saves costly bends and eases the installation. It also absorbs surge pressures, vibration and stresses caused by soil movement (e.g. in earthquake zones). Owing to its low weight the handling at site is significantly easier compared to, e.g. metal pipes. The pipes can be supplied in long lengths which increases the efficiency on jobsites due to less frequent jointing requirements and the faster joining process itself.
Excellent chemical and abrasion resistances offer a further benefit in application and do not require any corrosion protection (such as cathodic protection systems which are costly and require regular maintenance).
Carbon black content allows long-term installation exposed to direct sunlight as well as mechanical material performance enables installation in − 40°C up to +60°C environment.
PE pipelines will provide maintenance free operation with long life time expectancy (>100 years).
A polyethylene pipeline has an expected life time at a temperature of 20°C of more than 100 years and is maintenance free.
More information is available from: www.agru.at