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.


Time-Dependent Crack Growth in PE [PE]

 

Plastic Pipes Conference Association # 1998 Gothenburg

Bradley, Slay, Self, Register, Lamborn

The crack growth rate in HMN 5202 and HXM 50100 polyethylcne has bcen studied as a function of stress intensity using deeply notched three-point bend specimens. l'he load-line displacen~entin response to a static applied load has been measured, with tlie material compliance as a function of time determined from the specimen compliance prior to the initiation of crack growth. Measured specimen compliance as a function of time after crack growth begins is used to determine crack g r o w ~ hrate as a function of stress intensity. The crack growth rate has been shown to be a fi~nctionof stress intensity. giving the same crack growth rate h r very different combinations of load and crack length. tvith excellent repeatability. The experimentally determined crack growth rate as a Cunction of stress intensity has beell compared to theoretical predictions by Willia~nsand Scliapery. This comparison implies that both critical crack tip opening displacement, 6,,, and critical energy rclease rate, G , , increasc with increasing crack q r o ~ t l rate. i The results also show that the crack growth rate is significantly reduced by plane stress conditions at the surface of tlie specimen.

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

Related papers

2021 Amsterdam : EXPERIMENTAL DETERMINATION OF THE EFFECTS OF LIQUID HYDROCARBONS ON THE LONG-TERM CREEP RUPTURE PROPERTIES OF PRESSURE PIPE GRADE UNPLASTICIZED POLYAMIDE-12

Author(s) : James F. Mason, Akshay Ponda, Hermann van Laak, Buc Slay

The effects of liquid hydrocarbons on long term strength of pipe grade thermoplastic resins is an important consideration when designing pressure pipe for use in the oil and gas industry. There is an extensive body of work going back several decades descri bing these effects for pipe grade polyethylenes, and all...

2018 Las-Vegas : Extrusion of thick wall pipes using a new bimodal PE 4710/PE 100 resin

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...

2014 Chicago : Rapid Crack Propagation – Observations of Critical Pressure and Critical Temperature Relationships of Polyethylene Pipes

Author(s) : Ashish M. Sukhadia, Mark J. Lamborn, Pam L. Maeger

Over the past several years, we have conducted extensive investigations of the Rapid Crack Propagation (RCP) behavior of Polyethylene (PE) pipes. While the typical data of interest is the Critical Pressure (Pc) and/or Critical Temperature (Tc), we chose to take our investigations further by exploring and generating...

2014 Chicago : The Effects of Dual Cooling on the Rapid Crack Propagation Performance of Polyethylene Pipes

Author(s) : Mark J. Lamborn, Pam L. Maeger, Rick E. Kunc, Vivek Rohatgi, Paul J. DesLauriers, Ashish M. Sukhadia

Dual cooling is a post-extrusion cool down process employed for polyethylene (PE) pipe, whereby either water or ambient air is forced through the pipe bore following extrusion, in order to accelerate cooling. The primary benefits offered by the dual cooling process are increased production rates and reduced resin...

2010 Vancouver : Experimental Investigations of the Rapid Crack Propagation Performance of Polyethylene Pipes

Author(s) : M.Lamborn

Good resistance to Rapid Crack Propagation (RCP) is considered to be important to the field performance of polyethylene (PE) pipe. Even though RCP occurrences in PE pipe are very rare, it remains important to understand the RCP phenomenon to ensure that pipes are designed to avoid RCP events. The characterization of...

2006 Washington DC : Rapid Crack Propagation Failures in HDPE Pipes; Structure-Property Investigations

Author(s) : Krishnaswamy, Leevers, Lamborn, Sukhadia, Register, Maeger

The influence of molecular architecture on the rapid crack propagation (RCP) resistance of a wide variety of high-density polyethylene (HDPE) pipes was investigated. It was concluded that high molecular weight, high crystallinity and a relatively narrow molecular weight distribution are important architectural...

2006 Washington DC : S4 Critical Pressure and Critical Temperature

Author(s) : Maeger, Vanspeybroeck, Lamborn, Mamoun, Leevers, Oliphant

As polyethylene pressure pipes enter the global marketplace under an ever-wider range of operating conditions, there is increasing emphasis on their rapid crack propagation performance. It is important that both producers and end-users are able to rely on the robustness of the rapid crack propagation test results and...

1998 Gothenburg : Long Term Durability of Cross-Linked PE Tubing Used in Chlorinated Hot Water Systems

Author(s) : Gill, Knapp, W.Bradley, L.Bradley

The objectives of this research are to better understand the degradation of cross-linked polyethylene (PEX) tubing subjected to pressurized, hot chlorinated water in flow-through systems (like home plumbing) and to estimate its service lifetime. PEX tubing was subjected to pressure testing with flowing hot,...

Members of the Association

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