System Pressure Rating & Residual Life
Plastic Pipes Conference Association # 2004 Milan
Zhou, Palermo
ISO MRS and ASTM HDB rating systems have been successfully used for more than four decades in Europe and North America. MRS differentiates well the three generations of HDPE materials by classifying them as PE63, PE80 and PE100. However, HDB classifies all three generations of HDPE as only one PE 3408. When calculating MOP, MRS uses a minimum design coefficient of C=1.25. HDB uses a maximum design factor of F=0.5. C (1 F ) = 0.63 . In order to compare these two rating systems on the same page, design reference strength (DRS) is introduced. MRS is connected with DRS through the parameter coefficient, Cp, and HDB with DRS through the parameter factor, Fp. For a given HDPE that minimally meets ISO 9080 and ASTM D 2837, Cp and Fp are 1 and 1.53 respectively. C p (1 F p ) = 1.53 . The ultimate design coefficient, C ultimate = C × C p = 1.25 , and ultimate design factor, Fultimate = F × F p = 0.77 . C ultimate (1 Fultimate ) = 1.03 . This means the current MRS and HDB rating systems are equivalent and have the same design baseline. Nevertheless, since the minimum requirements in D 2837 are too low, HDB fails to differentiate HDPE materials. A detailed step-by-step analysis reveals the similarities and differences of the two rating methods. A possible revision to D 2837 to harmonize the two rating systems is given. This paper also discusses the important end-use parameters of application temperatures and design times.
Related papers
Author(s) : Chris Ampfer, Gene Palermo, Ernest & Oren Lever
This paper looks at the origin of the 10% allowable scratch depth rule for polyethylene (PE) pressure pipe developed in 1971 and research that has been performed over the years since its inception to determine the validity of this rule. The 10% rule has been used by natural gas pipeline operators since the 1970’s to...
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...
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...
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...
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...
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...
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...
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...
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...
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...
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...
Author(s) : Rob. J. Fox, Dr. Gene Palermo
CSA Z662 is the Standard for the use of plastic pipe in Canadian oil and gas pipeline systems. This paper will give an overview of the recently approved revisions to CSA Z662-11 “Oil and Gas Pipeline Systems”, which will be published next year. These revisions include the following : - RCP Requirements for PE pipe, -...
Author(s) : Dr. Gene Palermo
The scope of this paper is to clarify the various pipe material designation codes and other terms ( PE 4710, PE 4710 PLUS, PE 100, PE 100 RC and PE 100+ ) that are used in the piping industry for high density polyethylene (HDPE) materials. These are the benchmark “high performance” HDPE materials used worldwide for...
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...
Author(s) : G.Palermo
Manitoba Hydro is the electrical and natural gas utility for the province of Manitoba. A project to expand the existing natural gas system was initiated in 2005 which required the installation of a 29 kilometer (18 miles) main to connect a new town to the existing system. Project financial restrictions could not be...
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,...
Author(s) : Lever, Palermo, Wright, Oliphant
The piping industry has a need for a well-founded methodology to predict lifetime of pipeline components subject to stress concentration. Another useful tool would be a method to assess the impact of manufacturing processes on the slow crack growth (SCG) properties of a resin that can be used for process control in a...
Author(s) : Belforte, Gerard, Palermo, Guerra
South America is a region with a fast increase in economic growth and energy needs, and natural gas represents a strategic energy source not only for producers like Argentina but also for net importers like Uruguay and source-differentiated countries like Brazil. The fast development of the economy leads to request of...
Author(s) : Chang, Zhou, Michie
MTD Pipeline LLC is a joint venture between Martin Marietta Magnesia Specialties LLC and The Dow Chemical Company. A nearly 30 miles of high density polyethylene (HDPE) pipeline project in northern Michigan is serving as the latest example of technology evolution for polyethylene (PE) pipe used in underground pipe...
Author(s) : Palermo, Vibien, Oliphant, Kosari
The corrugated HDPE pipe industry is considering the responsible use of recycled materials in their pipe production and also in their pipe standards. One of the key requirements for successful use of recycled materials is ensuring performance of the resulting HDPE corrugated pipe. As slow crack growth (SCG) has been...
Members of the Association
