Helmuth Rijnhart
Papers # 2016 Berlin
As the cost of raw material is the dominant part of cost price in plastic pipe, pipe producers internally check on scrap rates and overweight to get the lowest cost price.
Scrap rates are mostly defined as start-up scrap. But scrap is also production that is in not in spec, production of pipe that has burning spots, black spots etc. If this is all calculated, scrap rates of 10-15% are not a uncommon.
Overweight is all weight of the pipe that is caused by making pipe heavier than determined by the minimum diameter and the minimum wall thickness. Most pipe producers define as overweight the weight of the pipe bigger than determined by the centre of specification. Doing so, these pipe producers already accept overweight in PVC pipe up to 5% and in PE pipe up to 8,5%. Knowing that the average extrusion line produces per year pipe worth 10 times the investment in that line, the cost of overweight is much more dominant than the depreciation and interest cost on the line.
By applying modern controls, like inline wall thickness scanners with haul-off control, gravimetric control to dose a constant mass flow of raw material to the extruder, and Automatic Thermal Centering on the die head, Overweight can be reduced significantly and labour cost can be reduced. At most of the extrusion lines, devices to reduce scrap rates and overweight have pay back times less than 12 months.
By applying modern control strategies, that fit in the “Industry 4.0” definition, it is possible not only to reduce scrap rates and overweight, but also optimize output and energy consumption. By constantly comparing settings and actual values against a calculated optimum, both operators and management constantly will have access to the best quality information to make sure that best performance in many perspectives is achieved. Using this technology during start and stop of the extrusion process, will help minimizing start and stop scrap rates.
Continuously collecting a wide set of data in the extrusion line makes Big Data Analysis possible, to explore, detect and eliminate root causes of non-optimal performance.
Related papers
Author(s) : A. Marangoni
The quality of infrastructures is a key driver for maximizing the performance of the utilities networks and minimizing the environmental impacts associated with their operation. The water and sewer pipes are key network elements to guarantee a satisfactory service to the citizens. Their end-of-life management is an...
Author(s) : Drew Mueller, Peter Dyke
HDPE Pipe holds a dominant position in several markets in North America: natural gas distribution, oil patch, mining, landfill and geothermal. So why are polyethylene’s municipal water and wastewater market shares so much lower than these other industries? How has the polyethylene industry been successful in growing...
Author(s) : Tom Stewart, Richard Hicks, Patrick Vibien, Lance MacNevin
Arguably, broadband technologies have become as vital to society as water delivery, waste removal and energy distribution. However, the role of plastic conduit in broadband is often overlooked within the piping industry and society in general. HDPE conduit is an essential component to the build -out of 5G cell...
Author(s) : Prashant Nikhade, Farraj Tashman
In the Middle East and India, PE pipes have expanded their applications in a big way for water supply, industrial effluents, corrosive chemical transportation, slurry transportation, city gas distribution networks and agriculture irrigation purposes over ductile iron, cast iron and other conventional pipes. PE...
Author(s) : Christian Schalich
Plastic pipes for infrastructure and building applications are precisely specified with regards to wall thickness and diameter. Pipe manufacturers use different measuring methods in order to ensure the required dimensional accuracy and maintain a constant high quality. This paper introduces a measuring system based on...
Author(s) : Eng. Grigorios Vigellis, Eng. Mohamed Hageb
Continuous development and innovation in the production of plastic pipes made by high density polyethylene (HDPE) has enabled the industry to produce much larger diameter systems than ever believed possible. The enablers for production of such large plastic pipes are three main pillars: continuous innovation...
Author(s) : Lukas Travnicek, Pavel Hutar, Jan Poduska, Andreas Frank, Florian Arbeiter, Jaroslav Kucera, Jiri Sadilek, Gerald Pinter, Lubos Nahlik
The application of recycled material in pressure piping systems has been considered lately – it was suggested, that the recycled polyethylene could be used as a part of a multilayer pipe together with virgin material. This type of pressure pipes is not availableon the market yet, so their properties can be only...
Author(s) : Yoshikatsu NISHIDA, Yukihisa YAMADA, Masaya IWASAKI, Masaru TOMOBE, Yuichi KOUGA
By using polyethylene as the main material for this fire extinguishing device pipe, a resin-made fire extinguishing device is developed that is maintenance-free for eight years and can cope with the abnormal heat generation of lithium ion batteries. In order to prevent the internal extinguishant from permeating and...
Author(s) : Andrew J. White, Paul Dietz
FP-Pigments is a global manufacturer of a unique series of titanium dioxide pigment products and have been supplying the coatings, plastics, paper and inks markets for over 10 years, helping our customers reduce their raw material costs while maintaining product quality and performance. We have plants in both...
Author(s) : E. Boccaleri, L. Palin, G. Rombolà, M. Milanesio
In the last decades, research on nanostructured materials as additives for plastics involved several polymeric matrices, but only limited studies and publications involve PVC. In this work, the context of rigid application of PVC (U-PVC) for pipes application was targeted, in order to test and evaluate the structural...
Author(s) : Vivek Rohatg, Gregor Hiesgen, Mark J. Lamborn, Ashish M. Sukhadia, Douglas E. Simpson, David W. Borrego, Pamela L. Maeger
Maintaining dimensions within specifications is problematic for the extrusion of large diameter thick-wall polyethylene (PE) pipe (> 75 mm wall) due to sag caused by insufficient resin melt strength. However, sag can be controlled through careful resin selection and optimization of the pipe cooling process. This paper...
Author(s) : Sarah Eisenstat, Peter Dyke
Many cities in the US are operating their water utility on a “manage to fail” basis, meaning they are replacing >100-year-old pipes at a cycle time of over 150 years. At this rate, most of the pipes will have failed before they can be replaced. Ft. Wayne, IN made the realization that PE pipe is the solution due to its...
Author(s) : Marc van Loo (Dr.), Constant Van Aerschot, KumHoong Lou
In many parts of rural developing Asia and even some parts of Africa, sewerage from households is often discharged directly to the surrounding. This unfortunate fact means that many waterborne diseases such as cholera, dysentery and typhoid continue to afflict these communities. Numerous efforts from governments,...
Author(s) : Christian Schalich
This paper introduces a new technology based on millimeter waves. It provides a noncontact, non-destructive, online measurement of inner and outer diameter, ovality, wall thicknesses, and sagging (sagging of the melt during solidification at a too high viscosity) of large plastic pipes during the extrusion...
Author(s) : Pavel Hutar, Jan Poduska, Pavol Dlhy, Andreas Frank, Jaroslav Kucera, Jiri Sadilek, Gerald Pinter, Lubos Nahlik
This paper investigates possible use of recycled material as a part of a multilayer polyethylene pressure pipe system. Crack propagation in different configurations is simulated. Lifetimes of pipes containing recycled material are calculated. Results are compared with lifetimes of pipes made of virgin...
Author(s) : Xiaoying Lu, Yujie Wang, Qiang Huang, Chunyan Xu, Guangyu Zhu, Aimin Xiang, Linmei Wu, Yanfang Wang
The determination method of metal elements for polyethylene pipes was reported in this paper, the difference in metal elements content between raw materials and recycled materials was analyzed. The results showed that raw and recycled materials in polyethylene pipes were effectively distinguished via metal element...
Author(s) : C.B. Dandekar
Plastic Corrugated Piping System (PCPS) was introduced in India in 2001, much later than the western world started using it for various applications. It received a mixed response from the Govt. Agencies, but was well accepted by the market, actual users and standardizing institutions. PCPS finds applications in...
Author(s) : Andreas Frank, Isabelle J. Berger, Florian Arbeiter, Pavel Hutař, Gerald Pinter
Due to the high slow crack growth resistance of modern polyethylene pipe grades a reliable lifetime assessment of pipes with focus on stage II failure has become challenging. The current paper presents a scientific approach for a fracture mechanics lifetime prediction based on Cyclic Cracked Round Bar (CRB) Tests....
Author(s) : Miroslav Stanimirov
Long length pipes, which are these days often used as high quality and cost efficient solution in various types of projects, are actually product of a problem that PE pipe installers were facing in early days of plastic pipe business. That problem was low reliability of PE pipe joints. The only logical solution was to...
Author(s) : Sergey Shalyapin
Steel reinforced twin wall pipe (SRTWP) is a new generation of corrugated plastic pipes which has a multilayer structure with an omega-shape steel profile indented into a polymer wall whereby these pipes combine the best benefits of plastic and metal solutions – high corrosion, abrasion and chemical resistance, low...
Members of the Association
