Assured quality of butt fusion and electrofusion welding of PE100 pipe

 

Papers # 2016 Berlin

The many benefits of PE100 pipe materials include flexibility and toughness in addition to being relatively light products that are not subject to corrosion and expected to last well beyond the design lifetime [1]. It is also a distinct advantage that end-load resistant joints can be made using butt fusion (BF) and electrofusion (EF) welding. There is, of course, always room for improvement and Exova has continually provided solutions to the difficulties identified for both BF and EF welding processes [2, 3]. In addition to the new training standard reported at the last conference [4] that is expected to result in a step change in improvement of site practice, Exova is active in a variety of other ways to ensure that quality is assured as now presented.

Development of BF welding conditions and testing has been previously been reported by Exova [4, 5] and Beech et al [6-9] in recent conferences. The latter work was funded by the PE100+ resin producers and completed in collaboration with other laboratories. Results have been used to harmonise conditions within ISO 21307 [10], but the work was incomplete as highlighted by Striplin et al [11]. 

Exova therefore undertook further work to consider the influence of ambient conditions on the BF welding process, which included consideration of forced cooling in an attempt to reduce the duration of the welding cycle. The range of pipe wall thickness that may be welded was also extended. This included consideration of all welding conditions within ISO21307 in addition to those used by the gas industry in the UK [12]. Consideration was also given to the accommodation of thick section welds within test methods. In addition to short term testing, long term and non-destructive testing has been used to report on the quality of welds produced over a wide thickness range (30- 90mm) and in 4 different welding conditions. Although ambitious, the project has resulted in significant achievements and provides a new baseline for both welding conditions and testing in the future.

End-user stakeholders of the pipe materials have requested more realistic test methods that enable better understanding of the performance of the products, both in terms of type testing of EF fittings and quality control of joints in the field. The approach that Exova would recommend includes a performance type test based upon resistance to contamination, first introduced in the UK decades ago [13] and hailed by local manufacturers as a breakthrough. The second consideration is the availability of adequate handling equipment, notably clamps, especially for coiled pipe [14, 15]. Although pressure testing may be used for type tests, quality control tests need to be more practical and a shear test has been developed that relates directly to service performance of the joint [16]. Finally, modern NDT methods based upon microwave and phased array ultrasound has been established to provide the best non-destructive indication of long term performance [17-18].

Please note that the whole article content is available on PPCA website onlySource : 2016 Berlin


Related papers

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 2018 Las-Vegas

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...

Investigation of the failure behavior of polyethylene electrofusion sockets

Author(s) : Isabelle J. Berger, Andreas Frank, Gerald Pinter, David Nitsche, Dirk Petry 2018 Las-Vegas

Electrofusion (EF) sockets constitute a well-established and practically proven technology for the joining of polyethylene (PE) pressure pipes. As for the pipes, the potential lifetime of such welding connections is beside other properties also depending on the resistance against slow crack growth (SCG). The current...

The world's first class 3 safety related nuclear PE4710 piping project - 10 year review

Author(s) : Lonnie Corley, Dane Chang, Harvey Svetlik, Matt Brandes, Thomas Musto, Frank Schaaf, David Fink 2018 Las-Vegas

This paper presents a brief overview of a challenging project at the Callaway Nuclear Power Plant where HDPE was utilized to replace degraded steel buried piping in a Safety Related water system. Callaway was the first Nuclear Power plant to obtain NRC approval and successfully place the HDPE piping system into...

Asset management of polyethylene gas networks

Author(s) : Ian Aldridge, Declan Robinson, Dave Smart, Chris Reed, Martyn, Greig, Trevor Stafford, David Christie-Lowe, Alec Erskine 2016 Berlin

For the UK polyethylene (PE) gas pipe network, the first installations now exceed 40 years in the ground, with an original design life of 50 years. It was thus timely to review the current condition and performance history of these first generation PE materials. A major 4 year project was started in 2010 to examine...

Big data, big difference

Author(s) : Nick Mark, Eric Bridgstock, David Carey 2016 Berlin

An insight into a unique approach to the management of electrofusion and butt fusion joint quality on polyethylene pipelines. The presentation will reference experience and learnings from a system that has already been used in the field to great effect (see Abstract) and a new approach to butt fusion (see enclosed...

Quality control testing of joints in gravity flow plastic pipes

Author(s) : David Becerril García, Jacinto Cortés-Pérez, Ian D. Moore 2016 Berlin

Joint performance of joints in gravity flow buried pipelines is very important since joint failure could produce structural or service limits to the system. Standards have been developed to evaluate that joints have the necessary structural and leakage capacities which specify test methods that are not clear and do...

Chemical and Temperature Resistance of Polyethylene Pipes for Industrial Applications

Author(s) : Dr. Amaia Bastero, David López Piquer 2014 Chicago

The industrial sector has traditionally used metal pipes for transporting a wide variety of chemicals and highly corrosive liquids. When metal pipes are exposed to aggressive media, their lifetime is considerably reduced. Polyethylene pipes, have demonstrated since the 1950s to be a safe, reliable and cost effective...

Development of a Slow Crack Growth Resistance (Strain Hardening) Test for Assessment of Ageing PE Pipeline Materials

Author(s) : Sonya Pemberton, David Chrystie-Lowe, Sabah Rafiq, Karolina Modelska, Edward Ingham 2014 Chicago

A room temperature tensile test using thin films taken from the outside and inside surface of polymer pipes has been developed to study the slow crack growth resistance of ageing PE pipelines via analysis of their strain hardening behaviour. A range of PE materials in service since the early 1970s and 80s are studied,...

Prediction of residual lifetimes of small diameter polyethylene pipes

Author(s) : Márton Bredács, Andreas Frank, David Nitsche, Andreas Riha, Gerald Pinter 2014 Chicago

Within this paper the property and lifetime profile of four small diameter PE water pipes for house supply, which were installed between 1968 and 1992 in Vienna and Graz, Austria, were studied. Based on thermo analytical and structure analytical test methods the materials show still expected values for PE even after...

Very High Molecular Weight Polyethylene Resins with Improved Chemical and Abrasion Resistance

Author(s) : Dr. Dane Chang, Dr. David Marshall, Chris Cox 2014 Chicago

Plastic pipe applications often require polymers to have adequate abrasion resistance during usage. Although typical polyethylene resins have reasonably good resistance to abrasion and can be broadly used with a variety of chemicals, there are some demanding applications that require a resin with enhanced abrasion and...

Performance of Multilayer PE100 pipes upon ageing to chlorine dioxide disinfectants

Author(s) : David Hill Jean Carmier 2012 Barcelona

A multilayer pipe named Excel Plus® made with a protective inner layer in PVDF was developed by GPS PE Pipe Systems, an Aliaxis group subsidiary. In order to assess, in accelerated mode, the resistance of this pipe against chlorine dioxide, a test sample exposure facility was built at the Aliaxis corporate R&D...

The water for the world™ initiative: reflection on 5 years of experience

Author(s) : Jane Toogood, Dorothea Wiplinger, Christophe Salles, David Walton 2012 Barcelona

Securing access to safe water and sanitation is recognised as one of the world’s most pressing societal and environmental challenges. Launched in 2007 by Borealis and Borouge,‘Water for the World’ is a programme platform to advance solutions, expertise and know-how to address this challenge. Activities are...

Evaluation of a novel Microwave based NDT inspection method for Polyethylene joints

Author(s) : Ken Murphy, David Lowe 2010 Vancouver

Exova is continuing in the long tradition of Pipeline Developments Limited (PDL) in the UK with research, development, testing, quality assurance (QA) and failure analysis of modern plastic pipe materials and joints. Along with this ongoing work Exova has assessed various non destructive testing (NDT) techniques in an...

The BFF Test: An Un-Notched Stress Crack Test for Evaluating Resin Blends Containing Recycled HDPE for Use in Corrugated Drainage Pipe

Author(s) : Richard Thomas and David Cuttino 2010 Vancouver

The BFF test is an un-notched, constant load, stress crack test performed at elevated temperatures (70 or 80ºC) in deionized water. The test is a combination of the BAM test, developed in Germany in the early 1990s, the Florida Department of Transportation protocol for 100 year service lifetimes, and uses a dumb bell...

Optimisation of Butt Fusion Welding of Thick Walled PE100 Pipe

Author(s) : Lowe, Starkey, Powell 2006 Washington DC

With the increasing success of PE100 and usage of pipes of increasingly large diameter, concerns have been raised about the quality of weld performance with relatively thick walled pipes (>50mm), which has led to the current investigation. In addition to the consideration of welding conditions adopted in the UK,...

Solutions to Installation Difficulties with PE Pipelines

Author(s) : MacKellar, Lowe, Ingham, Ashdown 2006 Washington DC

Polyethylene (PE) is the preferred material for 90% of all water mains laid in the UK. The pace of renovation of dilapidated cast iron water networks has led to the increasing demand for coils of flexible PE pipe, driven by the efficiency of using less joints and taking up considerably less space in the congested...

New PE pipe material aids renovation of medium pressure gas pipelines in urban environment

Author(s) : Alessandro Soresina, David Walton 2004 Milan

AEM S.p.A. is the leading Italian company in the management of public utility services, based in Northern Italy (Milan), and operates in the sectors of electricity, gas and heat, telecommunications and other services which include both public and aesthetic lighting.The parent company, AEM S.p.A.have been listed on the...

The Abrasion Resistance of Polymers Used in Slurry Transport Systems

Author(s) : Lowe, Marshall 1988 Bath

A Rotating Pipe Drum Test has been developed to assess the abrasion performance of plastics pipes to an extpnt where most test variables are understood. The procedure involves the rotation of relatively short pipe lcngths containing slurry on a conventional bail mlll. In the rest, the pipe surface repeatedly passes...

The Abrasion Resistance of Polymers in Slurry Environments

Author(s) : Lowe, Marshall 1985 York

A new test has been developed to evaluate the abrasion performance of different pipe materials. The Rotating Pipe Test simulates sliding bed flow of a slurry and gives quite excellent data reproducibility. The influence of sample geometry and slurry changing frequency and particle size have been assessed. The effects...

Lifetime of Electrofusion Joints

Author(s) : Lowe, Ingham, Starkey 2008 Budapest

Members of the Association

BOREALISBOROUGEFormosa Plastics CorporationINEOS O&PIRPCKazanorgsintez PJSCKorea Petrochemical IND. Co., LTD (KPIC)LyondellBasellPetroChina Dushanzi Petrochemical CompanyPRIME POLYMERSABICSCG Chemicals & Thai PolyethyleneSinopecTASNEE
TOP