Key items for Plastic Pipes Conference

Testing for industrial conditions  

Markus Haager from AGRU Kunststofftechniek, based in Austria will report on test results of polypropylene pipes used to transport sulphuric acid for the last 21 years.  

"Polypropylene pipes are increasingly used for industrial applications. Their excellent corrosion resistance to a wide range of chemicals such as acids, bases, alcohols and esters is generally known," Haager points out. "Whereas conventional methods such as immersion tests or internal pressure testing of these pipes tells us much, we wanted to know about their long term behaviour and then within a real situation."  

To gain this knowledge, Haager and his colleagues tested samples from a pipe that had been used to transport sulphuric acid (20%) in a steel mill for the last 21 years! Results from testing the PP random-copolymer (PP-R) were interesting.  

"DSC (Differential Scanning Calorimetry) and MFR (Melt Flow Rate) investigations showed negligible deviations compared to new pipes," notes Haager. "Tests suggested that the bulk materials are still in good shape. Furthermore the mechanical properties of the pipes were investigated by tensile and impact tests. Both tests demonstrated that requirements of relevant standards are still fulfilled by the used pipes." 

"Finally welding tests were performed to find out whether the pipes can still be welded to each other and also to new pipes. The welds were evaluated with short-term tests according to DVS and it was shown that the welding strength was in the same range as the welding strength of new pipes."  

The team also tested PP pipes that were used to transport cobalt chloride (18%) for 20 years. Neither the pipes nor samples taken showed any sign of damage.    

The benefits of Pipeline Innovation  

Professor Alessandro Marangoni from the prestigious Bocconi University of Milan will present a paper entitled 'The benefits of Pipeline Innovation'. It will detail the actual cost to Italian society of modernising Italy's old and porous water and sewer networks. He has also calculated the cost of doing nothing.  

His gap analysis has started to awaken the Italian psyche. By working closely with an independent team of experts, he has been able to acquire an accurate picture of the cost to society of outdated pipe networks: "Every year, water leakage is costing Italian customers as much as EUR 4 (USD 6) billion," he explains. "In Italy, cracked or broken water mains for example, have a leakage rate of 38 - 45%. Compare this to the best performers in Europe such as Germany's 8 - 15% or The Netherlands where not a single drop of water is permitted then the scale of the wastage is evident."  

The Professor has calculated that over the next 50 years, the Italian infrastructure will require 155,300 kilometres of water mains and 66,600 kilometres of sewers. For drinking water, the cost amounts to EUR 22.2 billion compared with iron. For wastewater, the cost works out at EUR 63.6 billion compared with iron and EUR 54.4 billion compared with cement.  

"Our cost comparisons will be of extreme interest to all stakeholders involved with the delivery of water and the dispatch of household waste. They not only evidence the need for urgent investment but also signal the most economical solution. The Benefits of Plastics Innovation are overwhelming."  

Dry system for PVC-O pipes  

Ignacio Munoz is director of Molecor, a company that specialises in developing manufacturing technology for PVC-O pipes. Munoz will tell the Conference that the full dry system for producing bi-axially oriented plastic pipes (PVC-O) has clear benefits over the batch method of production.  

PVCO pipe is PVC pressure pipe that attains a relatively high strength by re-orienting the molecular structure. Whereas conventionally extruded PVC pressure pipe has a maximum hydrostatic design basis (HDB) of 4000 psi, PVCO has a maximum HDB of 7,100 psi. This increased strength has prompted gas and water utility companies to use these kinds of pipes instead of traditional non-plastic pipes.        

Munoz says that the batch system of manufacturing these pipes provides a stable and flexible process and allows a high degree of orientation with raw material savings. "However, they are not that efficient in terms of energy, labour and output. They are also highly penalized by internal logistics," he explains.  

"New on-line systems that use air for drying in the manufacturing process provide significant energy and labour savings. In addition to greater speed and enhanced efficiency, they enable complete integration within one standard extrusion line. The result is a stable and reliable process that is highly profitable and works in a continuous way."  

"Manufacturers will also experience an easier start up with the on-line method. Given the superb quality of PVC-O and the easier and more affordable process, the material has a promising future."  

New grade of PE for gas pipes  

Can polyethylene pipe really replace large diameter cast iron and steel gas pipe? According to Jimmy Zhou, technical service leader for DOW in the US, a new grade of PE material fits the requirements perfectly.  

The high performance material is called PE4710 and the new grade has been introduced into ASTM standards. Zhou says that it differs remarkably from earlier grades of PE material.   

"The benefits of large diameter/high capacity PE gas pipe are obvious," he observes. "But questions have been raised by the U. S. Department of Transportation and gas utilities as to rapid crack propagation (RCP). Secondly, stress concentrations increase as pipe diameter increases for a given scratch. And lastly, there is the ability of thin-wall PE pipe to resist the forces associated with buried installations (buckling, crush) caused by earth loading."   "However, PE4710 addresses the key issues and concerns with outstanding resistance to slow crack growth and RCP, along with a maximum hydrostatic design stress 25% higher than PE3408 and 60% higher than PE 2406."  

"These properties will enable utilities to safely design for the use of large diameter and high SDR (up to SDR 26) PE4710 gas pipes to replace aging cast iron and steel facilities," he concludes.  

The three-day conference schedule will comprise the presentation of about one hundred papers, a trade exhibition and a social program. 500 participants are expected for what has become an ideal meeting place for delegates and the latest ideas from utility companies, technical and certification institutes, plastic pipe companies, equipment manufacturers, compound makers and other suppliers.   Conference keynote speaker is Ray Hammond, Europe's preeminent futurologist. His World in 2030 forecasts a "positive outlook for plastics," arguing that the material has an important part to play in overcoming future challenges.  

Conference key sessions will represent a wide interest of plastic pipe technology including

Market Growth Potential of Plastic Pipes and Case Studies for Novel Applications.  

Plastic Pipes XIV is organised by TEPPFA, PE 100 +, PVC4Pipes and the Plastics Pipe Institute. A new brochure with full program is available from the Conference website alongside registration and further information: http://www.ppxiv.com


More information: 
Zoran Davidovski
Tel:  +43 2236 43939 20
E-mail: zoran.davidovski@pipelife.com