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.


Performance of Scratched HDPE Pressure Pipe [PE]

 

Plastic Pipes Conference Association # 2006 Washington DC

Zhou, Chang

High density polyethylene (HDPE) pressure pipe may be scratched during installation. The scratches reduce the wall thickness and therefore increase the dimension ratio (SDR pipe). 1” SDR 11 pipe samples extruded from bimodal PE100/PE4710 and unimodal PE80/PE3408 pipe materials were used to investigate the effect of scratches on the hydrostatic performances. The 60o V-shaped notches along the pipe longitudinal direction were introduced to mimic the installation scratches. The percentage of notch depth over the minimum wall thickness was controlled at 5%, 10% and 15%. Hydrostatic test on the un-scratched and scratched pipe samples were conducted at 90ºC and 80ºC. The scratch sensitivity, SS, was established to study the impact of scratches on the failure times of the scratched pipes. SS was defined as the failure time of the scratched pipe divided by the failure time of un-scratched pipe at the same stress and temperature. The SS values were determined for these two benchmark pipe samples using the hydrostatic data at 90ºC and 80ºC. As the hoop stress increases, the SS values increase. The 3parameter Rate Process Method (RPM) was used to extrapolate the hydrostatic data at the elevated temperatures to the room temperatures. Up to 15% scratches, the bimodal PE100/PE4710 pipe was projected to last at least 100 years at 10 MPa/20ºC for PE100 and at least 25 years at 11 MPa (1600 psi)/ 23ºC for PE4710. The unimodal PE80/PE3408 pipe was projected to last at least 100 years at 8 MPa/20ºC for PE80 and at least 10 years at 11 MPa (1600 psi)/23ºC for PE3408 at 15% scratches. At the maximum operation pressure (MOP), both pipes were projected to last thousands of years according to this analysis methodology.

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

Related papers

2018 Las-Vegas : Design and qualification of PA-PERT pipe for oil and gas transportation

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...

2018 Las-Vegas : Effect of carbon black, compounding and pipe extrusion on the slow crack growth pent test result

Author(s) : Adriana Velasquez, Dr. Dane Chang, Dr. Siddharth Athreya

This paper studies the PENT results and how they vary based on sample preparation, equipment used, technique to place the sample as well as the number of heating cycles that the resin goes through after it leaves the manufacturing facility including those cycles needed to pre-compound virgin resin with a color...

2018 Las-Vegas : Preparation and studying of thermoplastic cross-linked polyethylene

Author(s) : Cheng Zhi, Mingyuan Hu, Kaige Duan, Chaoxi Zhou, Dongming Yu

The PE properties are obviously improved by crosslinking modified to TPEX, which can approach to that of PEX, while still remaining thermoplastic. It can be processed by the common forming method of thermoplastic; the products can be hot-melted and the scrap can be processed to be reused. The two-layer structure...

2018 Las-Vegas : Study on the resistance to external pressure test methods of plastic inspection chambers

Author(s) : Zhang Wei, Wei Ruoqi, Zhou Minghong, Zhou Mingwei,

This article gives a brief introduction of plastic inspection chambers in China. It focuses on the formulation of China's national standard for plastic inspection chambers and conducts the theoretical analysis and data validation of the key technical metrics in the standard for the following three tests: the...

2018 Las-Vegas : The influence of molecular design variables of bimodal HDPE on the slow crack growth resistance measured by accelerated methods

Author(s) : Cliff Mure, Siddharth Athreya, Dane Chang, Rujul Mehta

New generations of PE100 and PE4710 pressure pipe materials exhibit a superior balance of mechanical properties. The slow crack growth performance of these materials measured by traditional tests such as PENT and FNCT can exceed one year. Accelerated test methods, including strain hardening modulus, accelerated FNCT,...

2018 Las-Vegas : 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

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...

2016 Berlin : A New High Temperature Pressure Rated HDPE Pipe Resin Expands the Capability of Polyethylene Pipe

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...

2016 Berlin : The application of rainwater harvesting technique in the project at jiangsu factory

Author(s) : Zhou Minhong

Rainwater can be used not only for washing road and irrigation, but also for flushing toilet, washing clothes and industry use. Moreover, storm water regulation and storage facilities help reducing the burden of drainage piping system, cutting down the investment of storm water pipelines and lowering the possibility...

2016 Berlin : Underground engineering stress analysis of plastic inspection chambers

Author(s) : Zhang Wei, Wei Ruoqi, Zhou Minghong, Zhou Mingwei,

This article gives a brief introduction of plastic inspection chambers underground test, analyzes the stress borne by plastic inspection chambers from different angles combined with pressure sensors and strain gauges, sorts out some of the underground test data and analyzes the test data, and finally sums up the...

2014 Chicago : Essential Variables of Heat Fusion Joining of Polyethylene Pipe

Author(s) : Dr. Z. Jimmy Zhou, Jim Johnston

Heat fusion joining method has been widely used for thermoplastic piping materials such as polyethylene to form the “one-material” pipeline system. No additional 3rd party materials such as an adhesive are needed. The fusion procedures to ensure the quality of the joints could be different for different materials and...

2014 Chicago : Methodology to Determine Design Life of Assemblies of PE Pipe, Heat Fusion Fittings, and Heat Fusion Joints

Author(s) : Dr. Gene Palermo, Dr. Dane Chang, Dr. Jimmy Zhou

The scope of this paper is to provide information for the plastic piping industry on a test methodology that could determine the design life of heat fusion fittings and joints at the end user field conditions of operating stress, operating temperature and desired design life. This methodology is useful not only for...

2014 Chicago : Performance Evaluation of Notched PE80/PE3608 Pipe Using Ligament Stress Regression Methodology

Author(s) : Dr. Z. Jimmy Zhou, Dr. Dane Chang

External flaw could be introduced into pipe wall during the transportation, installation and service processes of polyethylene pipe. The performance of non-flawed pipe is well addressed by both the standard stress extrapolation methods specified in ASTM D 2837 and ISO 9080. However, there are very limited data for...

2014 Chicago : Study on Structural Integrity of Plastic Inspection Chambers

Author(s) : Zhang Wei, Wei Ruoqi, Zhou Minghong, Zhou Mingwei, Lin Baoshu, Xiao Lingli

The plastic inspection chamber is one of the rapidly developing products in the field of drainage in China for the past few years. At present, plastic inspection chamber is mainly made of PP, PE, PVC and so on. The manufacturing technologies include injection molding, rotational molding, mechanical assembly and...

2014 Chicago : Very High Molecular Weight Polyethylene Resins with Improved Chemical and Abrasion Resistance

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

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...

2012 Barcelona : Ligament Stress Regression of Notched PE100/PE4710 Pipe

Author(s) : Z. Jimmy Zhou

(Keywords : Polyethylene pipe, ligament stress, regression, notch depth, lifetime.) Hydrostatic test was conducted on notched PE100/PE4710 black pipe specimens at various temperatures and stresses. Hoop stresses were normalized to ligament stresses by taking into consideration of the effect of wall thickness reduction...

2012 Barcelona : The application of plastic inspection chamber for drainage in China

Author(s) : Zhou Minhong

As the key component of underground piping network for drainage, plastic inspection chambers have many major advantages and are also being applied more and more widely instead of traditional brick-built ones. Users become familiar with this new technique gradually. However there are two major problems which have...

2010 Vancouver : Stress intensity effect on slow crack growth in scratched polyethylene pipe

Author(s) : J.Zhou

Stress intensity in Polyethylene (PE) pipe is determined by applied stress, defect size, pipe diameter and DR (dimension ratio of outside diameter to wall thickness). For the same stress, stress intensity varies as the defect size and the pipe diameter change. Defects may be introduced into the pipe wall after it is...

2008 Budapest : Advanced Bimodal MDPE for Piping Applications

Author(s) : Michie, Chang, Whited

The first NA produced bimodal MDPE pipe resin developed through unique molecular architecture offers significantly better resistance to slow crack growth and rapid crack propagation than traditional unimodal PE2708 / PE2406 products. This high performance resin extrudes well on conventional equipment, has good melt...

2008 Budapest : Study on the Consumption of Polyethylene Pipe Materials In China

Author(s) : Dongmei Zhe, Ruoqi Wei, Chang Liu, Ye Hua, Yu-e Li

The statistic data of the consumption of polyethylene pipe materials in China has been shown in this paper. The developing trend of polyethylene pipe materials in the following 5 to 10 years in China has been studied and the predicting data of the consumption of polyethylene pipe materials in China has been shown in...

2008 Budapest : The next gas Fronteer

Author(s) : Zhou Minhong

The advanced bimodal PE4710 materials enable its applications in large diameter gas pipe to replace cast iron and steel pipe. Among the three key field performances, the pressure rating is independent of pipe diameters. However, the SCG and RCP properties are dependent of pipe diameters. As pipe diameters increases,...

Members of the Association

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