TPI April 2009

projects. Plastic tubes are gaining ground in the areas of sanitary, air conditioning and heating technology, and are increasingly displacing the traditional materials.

Wasserfaches, German Association of the Gas and Water Industry) show this. Plastic tubes are increasingly being used in nominal diameters, which used to be the stronghold of concrete and steel tubes. This is mainly due to the advantageous characteristics of plastic tube systems. They can be installed easily and inexpensively, last a long time (about 100 years), are good when it comes to maintenance and repairs, and can be used very well to remedy existing, defective tube systems. Plastic tube systems are long lasting and can be recycled at the end of their lifespan. In addition, a scientific study confirmed that sewage pipes made of plastic offer better ecological performance. Upon the initiative of the KRV and the Europäischer Dachverband der Kunststoffrohr-Industrie (TEPPFA), the European Association of the Plastic Tube Industry, a study on environmental risks in communal sewage systems was carried out. ‘Study of the performance of different tube systems or tube materials for municipal sewage systems with special consideration of the ecological effects during the period of use’ by Prof Dr-Ing Stein & Partner GmbH also included the cooperation of an external European expert committee. According to Stein & Partner, the study, under consideration of the limitations of the analysed data to pipes with a maximum age of 30 years and a maximum diameter of 800mm, concluded that “ sewage systems using bendable, soft tubes show significantly better ecological performance because of lower damage rates and risks with regards to infiltration and exfiltration. ” n What are the current trends in plastic tube engineering? Plastic tube systems are becoming more diverse and more powerful. Further development of plastics and improved production or process technology allow for products and solutions tailored to specific demands. This leads to the fact that the areas of use for plastic tube systems are expanding. Further advances are expected in the area of remediation of existing, defective sewage and potable water networks. Here, the technological and economic advantages of plastic tube systems are brought to bear. We also expect rising demand for plastic tube systems in mechanical services for buildings. There are many options in this area. In Germany, there is more refurbishment than new construction. This offers great opportunities for our products. As of late, the technical pre-requisites for installation of gas pipes in residential construction have been met. This offers excellent opportunities for this sub-segment. Indeed, Germany’s future lies with a functional infrastructure. This also includes the creation of fibre optic networks. Plastic tube systems are excellently suited for this purpose. The fibre optic strands require long-lasting protective tubes, and the creation of the supply networks still needs to happen in Germany. n Sustainability: What are the features of plastic tubes in this regard?

n How do the tubes differ, depending on their different areas of use? Generally, plastic tubes differ in the plastics used and in their construction, profile, also known as design (ie the diameter, wall thickness, etc). In the area of supply and waste disposal, you will find mainly tubes of polyethylene (PE) and polyvinyl chloride (PVC), and increasingly in recent years, polypropylene (PP). Using the extrusion process, the plastics, which come as granulates or powder, are first heated and plasticised, so they can be shaped into tubes. These tubes can be made of a single material (homogenous solid-wall tubes) or such with two or multiple layers. Because of this, it is possible to configure tubes that comply specifically with the respective requirements of a certain medium and the external stresses in the underground environment. n Which special criteria must plastic tubes fulfil? Plastics and plastic tube systems must comply with various quality specifications, depending on their area of application, so they can be used accordingly and answer to multiple and varying demands. To this end, there are approval or prototype tests for the plastics as well as for the various tube systems. In addition to statutory requirements according to the European product standards, there are added requirements by authorities and users. In Germany, the Deutsches Institut für Bautechnik (the Institute for Structural Engineering) grants building inspection permits to manufacturers. Only after receipt of such a permit may producers install their products on private land. Specifications for potable water and gas tube systems are listed in the technical regulations of the Deutsche Vereinigung des Gas- und Wasserfaches (DVGW) (German Association of the Gas and Water Industry), while specifications for tubes for other uses are subject to the certification programme under DIN Certco. n Are there quality certificates for plastic tube systems? As construction products, plastic tube systems must comply with high safety standards. There are many marks in Germany and Europe, however these marks do not necessarily speak of the quality of the products. CE labelling for the plastic tube industry is still pending in Europe. Once the statutory requirements for the issuing of the CE-mark are fulfilled, manufacturers are required to label their products accordingly. However, the CE label is no guarantee of quality, but rather an administrative label used for free movement of goods in Europe. In Germany, users of plastic tube systems should pay attention to the DVGW label (gas and water), the official ‘Ü’ mark and/or the DINplus mark, depending on the intended use. Products with those labels can be used without worries. n Do plastic tubes have advantages over concrete or steel tubes? All materials and the tubes made thereof have specific characteristics. Compared to concrete or steel tubes, plastic tubes are fairly new products, however their market share is increasing. Publications of the DWA (Deutsche Vereinigung für Wasserwirtschaft, Abwasser und Abfall eV, the German Association for Water Management, Waste Water and Waste) and the DVGW (Deutsche Vereinigung des Gas- und

Interview supplied by Messe Düsseldorf GmbH

Kunststoffrohrverband eV Fachverband der Kunststoffrohr-Industrie – Germany kunststoffrohrverband@krv.de www.krv.de

Messe Düsseldorf GmbH – Germany www.messe-duesseldorf.com

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April 2009 Tube Products International