Papers
Plastic Pipes Conference Association # 2016 Berlin
Fu Zhimin, He Guoshan, Wang Wanjuan
Our research shows that in a torque rheometer test the greater the fusion degree of PVC-U is, the higher the minimum torque of the torque curve is, and the smaller the difference between the maximum torque and the minimum torque of the torque curve. According to the relationship, the method of evaluating the fusion degree of PVC (Df) was proposed and has been used in the production process control.
The fusion degree of unplasticized poly (vinyl chloride) (PVC-U) is an important factor affecting the performance of PVC-U pipes, especially the long-term hydrostatic strength. The Dichloromethane Test (DCMT, ISO 9852) is a standard method of evaluating the fusion degree of PVC-U but DCMT cannot evaluate the fusion degree quantitatively and the use of dichloromethane is an environmental concern. ISO 18373-1:2007 “Rigid PVC pipes -- Differential scanning calorimetry (DSC) method -- Part 1: Measurement of the processing temperature” and ISO 18373-2:2008 “Rigid PVC pipes -- Differential scanning calorimetry (DSC) method -- Part 2: Measurement of the enthalpy of fusion of crystallites” are both indirect methods of evaluating the degree of fusion. A local region of PVC pipe could be detected by DSC accurately. However, due to the terminal temperature of micro-crystalline melting progress having different calibrations, fusion degree cannot be measured directly by DSC.
Related papers
Author(s) : Mike Troughton, Amir Khamsehnezhad, Changyi Yu
When butt fusion welding polyethylene (PE) pipes in the field, it is often specified that the pipes must undergo fusibility testing in all combinations of suppliers, diameters and thicknesses before being fused in production. This is a very onerous and expensive task, but must be carried out to ensure that the PE...
Author(s) : Antonio Rodolfo Jr., Vanderley M. John
Unplasticised (U-PVC) and modified (M-PVC) pipes used in irrigation and infrastructure applications, outside diameter 326 mm, were evaluated according to various fracture mechanics methodologies, including fracture toughness (stress intensity factor KC and energy release rate GC, both at fracture), essential work of...
Author(s) : Greg Scoby, PE
This paper will detail the steps taken during adoption of HDPE for potable water systems improvements including material justification, creation of related specifications, investigation of available piping components, qualification of contractors and the construction/inspection of related systems. The City of...
Author(s) : M. Eckes & Dr. B. Baudrit, Dr. M. Troughton & D. Wylie, H. van Laak & J. Fritz
Unplasticized polyamide 12 (PA-U12) is increasingly being used in pipe applications, especially in the gas sector. However, the material behavior in the usual quality tests for pipe welds has not yet been thoroughly investigated. For this reason, two research institutes, worked in cooperation with a manufacturer of...
Author(s) : Suleyman Deveci, Nisha Preschilla, Sulistiyanto Nugroho, Birkan Eryigit
Carbon black (CB) has been used as a perfect and the cheapest solution to prevent photo degradation of polyethylene against UV light exposure. The effect of carbon black on the mechanical properties of polyethylene pipes was studied extensively, but only on well dispersed and distributed carbon black...
Author(s) : Ali Al Hammadi, Shane R. Schuessler, Mohamed Ali Awadh Jaber
This paper presents the advancements of HDPE piping materials , design and installation for use in ASME Class 3 piping systems at nuclear power plants. The paper will specifically introduce details of the first ever ASME Class III nuclear new build use of Class 3 HDPE pipe and fittings at the Emirates Nuclear Energy...
Author(s) : Joaquín Lahoz Castillo
Irrigation networks in Spain extensively make use of plastic pressure pipes systems. Some recent failures focus the attention on Rapid Crack Propagation phenomena. Larger high-pressure PVC-u pipes are involved in most incidences detected. The level of gelation of those pipes were measured per EN-ISO 1452-2 test...
Author(s) : Katsutaka Nakagami, Takahiro Kasatani
Osaka Gas improves various approaches to the improvement of polyethylene piping construction quality and executes the approaches. As a result of that, polyethylene pipes in Osaka Gas maintain high-quality and withstand the earthquakes. This paper shows these methods and performance against earthquakes in Japan. In...
Author(s) : Robert LeHunt
Nationally moderated and approved competency training Units and Qualifications have been established in Australia for plastics pipes within an overall Plastics Industry Training Package. Delivery of such Units over a 21 year period has contributed to a greater understanding of various plastics pipes materials,...
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) : Nick Mark, Eric Bridgstock, David Carey
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...
Author(s) : GREG SCOBY
The Plastic Pipe Institute Municipal Advisory Board recently completed the publishing of the “Generic Electro Fusion Procedure” covering 12 inch and smaller sizes. This publishing effort was conducted with a collaboration of water system operators and electro fusion fitting manufacturers specifically addressing...
Author(s) : R.J. Stakenborghs
Inspection of non-metallic materials is becoming more important as more and more non-metallic materials are used in various applications. One method for inspecting this non-metallic material is by electromagnetic radiation in the 1GHz to 100 GHz range, or microwave energy. Microwaves interact with material in a...
Author(s) : Sunwoong Choi, Tom Marti
Small scale, steady state (S4) testing per ISO 13477 is a lab-based procedure to determine the critical pressure at which a fracture will propagate following initiation in a given pipe material filled with a given test medium. The S4 test was originally developed for the natural gas industry using air as the test...
Author(s) : Takehiro Fujii, Hideo Hirabayashi, Kazushi Yamada, Hiroyuki Nishimura
It is important to stabilize the scraped surface of the polyethylene pipe, even if some operator scrape the surface of the polyethylene pipe. In Japan this automatic saddle scraper is widely used for improving workability and plumbing quality The newly developed “Automatic saddle scraper” consists of the casing unit...
Author(s) : Jörg Wermelinger, Oliver Hein
More and more a strong desire is noticeable for Non Destructive Testing (NDT) of welded PEjoints. The objective is to determine the long term performance of plastic piping systems made from PE100. To assess the impact of “mostly known defects“ on the long term performance of a welding, well-defined flaws have to be...
Author(s) : Ernst van der Stok, Jeroen Weller, Frans Scholten
This paper describes falling-weight tests as a first step towards determining the effect of residual stresses on the fracture behaviour of old PVC-U gas pipes at impact. Results showed that the level of surrounding pipe support, the quality of the material and the diameter of the striker had a major effect on the...
Author(s) : J. Weller, R.J.M. Hermkens, E.J.W. van der Stok
To prevent an enormous surge in the replacement costs of the Dutch PVC gas distribution grid a so-called Exit Assessment programme was started in 2004. This programme determines the actual quality of old excavated PVC-U and PVC-Hi pipes using a tensile-impact test at temperatures varying from -25°C to +47,5°C,...
Author(s) : Edward Ingham, Mike Shepherd
Exova has previously demonstrated that under normal operating conditions PE 100 pipes would be expected to have a lifetime of over 200 years, but in the UK concerns have been reported about relatively high failure rates within the water utilities of fusion joints, particularly for large diameter pipes. For some time,...
Author(s) : Alex Geringer
PolyethyIene pipes with their widely prized benefits, such as low weight, high flexibility and high pressure resistance to 16 bar, have become state of the art in dimensions up to d 630 mm (24”). Today, pipelines up to outer diameters of d 2000 mm (80”) or more are getting used frequently within different...