Our site uses cookies necessary for its proper functioning. To improve your experience, other cookies may be used: you can choose to disable them. This can be changed at any time via the Cookies link at the bottom of the page.


Effects of processing conditions on the fracture toughness

 

Additional Information - Posters

Plastic Pipes Conference Association # 1998 Gothenburg

Kuriyama, Narisawa, Shiina, Kotaki

Unplasticized polyvinylchloride (PVC-U) is extensively used in the pressure pipe applications. These pipes are usually designed to have 50 year lifetime. Although their service performance is generally very satisfactory , there has been a number of cases where the pipes fail at unexpectedly short times. One of the major causes of these early failures is faulty installation which leads to point loading such as is encountered in the case of the presence of stones pressing against the pipe wall. Another cause is manufacturing defects such as inclusions, voids and surface defects. These defects act as internal stress concentrators (!).

The resin properties, mold geometry and molding conditions are responsible for this manufacturing performance. Especially, the degree of gelation is an important processing factor which significantly influences the mechanical properties of the pipe. There are some studies which tried to correlate the gelation of the PVC-U pipes with fracture toughness °°”, However, there have been few studies which make clear the fracture micro-mechanism in relation to the level of gelation. In this study, we describe the toughening mechanisms of PVC-U pipes of several degrees of gelation based on microscopic observations.

Please note that the whole article content is available on PPCA website only :

Related papers

2021 Amsterdam : NEW CHALLENGING APPLICATION AS USED PEAT LAND HIGH PERFORMANCE PE-SGF PIPELINE SYSTEM FOR INTERNAL PRESSURE APPLICATION AS LARGE DIAMETER

Author(s) : Kensei INOUE, Mitsuaki TOKIYOSHI, Joji HINOBAYASHI, Takeshi KARINO, Toshinori KAWABATA, Takashi KURIYAMA

As the worldwide problems are over-population, unusual weather like as localized heavy rain and climate change. Against those problem, it has to need new projects to make a new agricultural field, drainage pipeline system and to spread the new underground irrigation system at peat land whereas spots of about 2 million...

2018 Las-Vegas : Field test of Glass fiber reinforced polyethylene pipe system at soften ground

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,...

2016 Berlin : Long-term behavior of glass fiber reinforced polyethylene

Author(s) : Mitsuaki Tokiyoshi, Philippe Vanspeybroeck, Kensei Inoue, Stephan Fullgrabe, Takashi Kuriyama, Toshinori Kawabata, Joji Hinobayashi

Big diameter polyethylene pipes used an important role due to superior performance (Flexibility, light weight, long lifetime and tighten joint) for water and industrial supply to several countries. However according to standard concerned Polyethylene pipes as like ISO4427 we are being used solid wall pipe with too...

2012 Barcelona : Estimation of surface void initiation of polyethylene pipes immersed in chlorinated water

Author(s) : Hiroyuki Kurio, Yuuji Yamamoto, Kenji Mizukawa, Takayoshi Yarimizu, Kentarou Nakata, Satoshi Saitou, Hisao Hirota and Takashi Kuriyama

In this paper, an acceleration test has been done to evaluate of the resistance of polyethylene pipes to the chlorinated water with varying the concentration of chlorine and test temperature. The surface defects like a void due to the delamination of film about 10-micron meter thickness were observed after the...

2010 Vancouver : Reliability of PVC-U Three Layer Pipes with Recycled Solid Core

Author(s) : Takashi KURIYAMA and Norio HIMUKAI

In order to make clear the reliability of PVC-U recycled pipes in relation to the three-layer structure, we described the deformation and fracture mechanism of wall of pipes based on non-destructive techniques of scanning acoustic microscopy (SAM). The results showed that the multiple necking deformation occurred...

2010 Vancouver : Studies to Theorize on the Minimum 100 Years Lifetime of the Polyethylene Piping System for Water Supply

Author(s) : Takashi Kuriyama, Kenji Mizukawa, Hiroyuki Kurio, Hiroaki Sakamoto

The Great Hanshin Earthquake that occurred on January 17, 1995, caused devastating damages to a large number of architectural structures such as high-rise apartment houses, and civil structures such as roads and bridges. This earthquake triggered the review of the quake-resistance standards of buildings and civil...

2006 Washington DC : Development of the Innovative Technology for Aged House Pipes

Author(s) : Akiyama, Higuchi, Nose, Toyoda, Kitano, Kuriyama

Since the year 2001, the Japan Gas Association has started the development of new renewal methods capable of cost reduction for modification work by inserting a new double-layered corrugated plastic pipe into the old gas pipe to encourage the modification of aged house pipes and upgrade the level of safety. The...

2004 Milan : Setting the Value of the Design Coefficient for A 0.3MPa Gas Supply Use PE Piping System in Japan

Author(s) : Akiyama, Kuriyama

The technical study group established by the Japan Gas Association examined the general design coefficient factor (C) to use polyethylene pipe to transport gas in Japan up to 0.3MPa. Because there are no results of the use of polyethylene pipe for gas in this high pressure range in Japan, we conducted a study...

Members of the Association

BOREALISBOROUGEFormosa Plastics CorporationHanwha TotalEnergiesINEOS O&PIRPCKorea Petrochemical IND. Co., LTD (KPIC)LyondellBasellORLEN UnipetrolPetroChina Dushanzi Petrochemical CompanyPRIME POLYMERSABICSCG Chemicals & Thai PolyethyleneSinopecTASNEE