New high modulus polypropylene helps the development of large diameter utility tunnel

Author(s) : Markus Gall, Reinhold W. Lang, Joerg Fischer, Ansgar Niehoff, Steven Schmidt

Despite recent efforts in promoting the utilization of recycled polymeric materials for more diverse and more advanced applications, there are still significant knowledge gaps with regards to the applicability of certain recyclate types for specific “re-use” purposes. When it comes to pipe applications, for instance,...

Author(s) : Liang Yu, Akshay Ponda, Dane Chang

Following the development of US shale oil and gas production since 2007, the demand for thermoplastic pipes with better corrosion resistance, and lower installation and operation cost than carbon steel pipe, has been growing significantly. Nylon 12 has been qualified for hydrocarbon transportation in offshore flexible...

Author(s) : Joerg Fischer, Paul J. Freudenthaler, Patrick R. Bradler, Reinhold W. Lang, Susan C. Mantell

This research addresses the effect of nucleation on the global aging behavior and the fatigue crack growth (FCG) resistance of commercial alpha- and beta-nucleated polypropylene random copolymer pipe grades (PP-R) when exposed to chlorinated water (5 mg/l free chlorine) at an elevated temperature of 60°C. Comparing...

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) : Joerg Fischer, Patrick R. Bradler, Reinhold W. Lang

In the present paper, a novel test system for conducting fatigue crack growth (FCG) experiments under superimposed mechanical-environmental conditions is presented. FCG experiments were performed on a polypropylene (PP) grade and a short-glass fiber reinforced polyamide 66 (PA-GF) grade as model materials. The...

Author(s) : Mitsuaki TOKIYOSHI, Gentaro TAKAHARA, Joji HINOBAYASHI, Toshinori KAWABATA, Takashi KURIYAMA

Glass fiber reinforced polyethylene pipes and fittings are controlled for bending characteristics (Strength and stiffness) for vertical and axial directions of pipe by spiral cross winding method. Generally, to use this method, it takes much stronger for vertical strength than axials cause of extruded direction,...

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) : Bülent Kuzkaya

Spiral wound pipes are becoming more and more important in larger diameter HDPE pipe production technology. The spiral wound structured wall pipes with profiles are already well known and used for several low or non-pressure pipe applications. This paper shows that spiral wound pressure pipes can fulfill the...

Author(s) : Sverre Tragethon, Martin Andersson

Global mega trends push for investments in sewage treatment capacity & efficiency. A trend is to go for central regional treatment sites, typically remotely located from dense populated cities. This calls for high capacity pressure sewage transmission pipelines. Reliable operation is of course of paramount importance...

Author(s) : E.J.W. van der Stok, K. Jacobson, S.O. Jansma, D. Lukes

The lack of a fast, universally-accepted test method for chlorine-dioxide-disinfected water is hindering the development of improved plastic piping materials. A literature survey was performed to define the degradation process in which chlorine dioxide affects the ageing of polypropylene, and to describe and reflect...

Author(s) : Andrew Wedgner, Muhammad Qasim, Arsenio Sembrano

Developments in material and pipe extrusion technology now enable converters to produce PE100 solid wall pipes of up to 2,800mm OD, but the use of such large diameters has been limited to industrial applications. This is now starting to change with water transmission pipelines of up to 1400mm OD being laid in the UAE...

Author(s) : Mark Yu, Dongyu Fang, Peck Tze Kang, Amos Tay , Fan Liu

Large diameter pipe was introduced in refineries and petrochemical plant, desalination plant and power plant for water intake and sea out fall in the past decade. PE100-RC material was selectedfor its excellent balance of superior bi-modal stress crack resistance and consistent high stiffness modulus. Under the...

Author(s) : Sayaka Yamada, Kazuhide Sekiyama, Shiori Watanabe, Kazuo Yamaguchi, Hideo Funahashi

Performance evaluation method of plastic mixers for high density polyethylene by using flow simulation is presented in this study. First, Mixing experiments were performed to find the mixing performance of mixers. Then, flow simulations using our original software in the mixers were carried out to know the important...

Author(s) : Norbert Jansen, Albert Lueghamer

Demand for polyethylene (PE) pipe continues to grow on a global basis. The performance properties of this tough, durable piping material are widely recognized by the engineering and design community on a worldwide scale and the range of applications expands. The evolutionary trend in PE piping systems has been very...

Author(s) : Dane Chang, Carl Baker

Due to its flexibility, toughness, and good resistance to corrosion and abrasion, polyethylene pressure pipe has been widely used for several decades in a variety of applications, including gas and water distribution, oil and gas gathering, and many industrial pipe segments. A significant limitation for polyethylene...

Author(s) : Aimin Xiang, Jianling Xie, Yuanzhang Yu, Yufeng Ren

PE-UHMW pipes standard and application in China are introduced. In this study, the tensile properties, charpy impact strength and abrasion characteristics of PE-UHMW pipes were investigated. These results demonstrate the excellent properties of PEUHMW pipes. A novel method of testing melt flow rate was also...

Author(s) : Suleyman Deveci, Dongyu Fang

Latest developments in polyethylene production (hexene co-monomer and bi-modality) have increased the material’s Slow Crack Growth (SCG) properties, which is a time dependent brittle type failure under low stress levels and one of the most important long term properties of pipe grade polyethylene materials. Despite...

Author(s) : Johannes de Bruin, Dr. Bert Dalmolen, Albo van Hateren

Normal High Density Polyethylene (HDPE) is commonly used as the fluid contacting element, or the “inner-liner”, in Reinforced Thermoplastic Pipes (RTP) and steel pipes up to 65 ºC. Through a modification of the HDPE polymer matrix, by adding nanoparticles, the E-modulus can be increased. Research shows that...

Author(s) : Joerg Fischer, Patrick R. Bradler, Reinhold W. Lang, Gernot M. Wallner

The present paper aims to study the crack growth resistance of a black-pigmented polypropylene pipe grade when exposed to elevated temperatures and various environmental media (air, deionized water, ionized water with a specific chloride content, and chlorinated water) under the simultaneous application of cyclic...

Author(s) : Shi Jingdong, Tan Gangqiang

FIBER REINFORCED LARGE DIAMETER POLYETHYLENE PIPE (GRPE) consists of fiberglass as the middle layer, and HDPE as inner and outer layers to provide required strength and stiffness. This composite pipe is made by spirally winding under hot melt condition, pipe pressure ranges is from 0.8 to 1.6 MPa. The fiber reinforced...