PE 80 Rating: Not Just a Pipe Dream |
| by Rolando Marasigan Jr. and Alfred King |
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Polyethylene is a strong and durable material that finds its way into demanding applications, such as piping. HDPE is suitable for gas and water pipe conveyance and in this application JGSPC is making inroads with the certification of Evalene HP10441 as PE 80 material. The certification was received on January 31, 2005 and is the culmination of a certification process that took over a year to accomplish. |
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What is PE 80 all about? In a nutshell, here are the answers to your Frequently Asked Questions about our PE 80 grade – Evalene HP10441. |
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What is PE 80? |
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It is a material designation based on the long-term strength of a material (the MRS, minimum required strength) in accordance with ISO 12162 (Thermoplastic materials for pipes and fittings for pressure applications). The MRS requirement is also listed under ISO 4427 (Polyethylene pipes for water supply). PE 80 materials have an MRS of 8.0 to 9.99 MPa, and pipes made from such materials can handle operating pressures of up to 232 psi and last for approximately 50 years. |
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Why is it important for our customers to be aware of this classification? |
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With the Evalene HP10441 PE 80 certification from an internationally recognized body, our customer converters will now be confident in using Evalene HP10441 to make PE 80 pipes, and pipe users will be assured of PE 80 pipe performance from said products. |
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PE 80 certification from Jana Laboratories
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How did Evalene HP10441 get PE 80 certified? |
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Evalene HP10441 was extruded with 2.5% carbon black by our technology partner Univation into 250 1” SDR 11 black pipes. These were then sent to the certifying laboratory, Jana Laboratories, where they were tested according to ISO 9080:2003. The pipes exceeded PE 80 requirements and Evalene HP10441 was subsequently given PE 80 Certification. |
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Who is Jana Laboratories? |
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Jana Laboratories, a Canadian full service pipe testing laboratory, is one of the few ISO 17025 certified facilities in the world fully capable of conducting hydrostatic pressure testing and chemical resistance testing. It was accredited by International Accreditation Services (IAS). Its state-of-the-art facilities are capable of handling hydrostatic pressure testing under conditions ranging from 23°C to 120°C and from 0 to 3000 psi. |
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How was Evalene HP10441 Rated According to ISO 9080:2003? |
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Evalene HP10441 pipes were subjected to different stresses, placed in 20°C, 60°C and 80°C water baths and observed until failure. At least 30 failure data points were collected for each temperature with distribution over 3 log decades. These data were used to make regression lines for each temperature and extrapolated to 50 years. The stress at the 50-year intercept (lower confidence limit, LCL) of the 20°C curve for Evalene HP10441 was 9.55 MPa. Thus, it was classified PE 80 according to the table below. |
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Table 1: Basis for PE pipe grade rating according to ISO 9080:2003 |
LCL Range @ 20°C, MPa | Classification | Minimum Required Strength (MRS) at 50 years, MPa | 3.15 – 3.99 | PE 32 | 3.2 | 4.00 – 6.29 | PE 40 | 4.0 | 6.30 – 7.99 | PE 63 | 6.3 | 8.00 – 9.99 | PE 80 | 8.0 | > 10.0 | PE 100 | 10.0 |
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How does Evalene HP10441 measure up to customer benchmarks? |
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Locally, our customers are able to test for the 1-minute “quick burst” pressure using their in-house equipment. On this test, Evalene HP10441 pipes give at least 50 psi higher quick burst pressure compared to current benchmarks Evalene HP17411 and competitor grade Borouge FB1460 (refer to Table 2). Some customers do not have to change pipe extrusion temperatures, going from Evalene HP17411 to Evalene HP10441. But others use 15-20°C higher temperatures on Evalene HP10441 compared to Evalene HP17411. Throughput is minimally affected. Other comparisons obtained by our Technical Service laboratory are shown in Table 2. |
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Table 2: Comparison between Evalene HP10441 (PE 80) & industry benchmarks |
Property | Unit | PNS Requirement | Evalene HP10441
(PE 80) | Evalene HP17411 | Borouge FB1460 | Extrusion Temperatures | °C | --- | 160 – 200 | 1-min Quick Burst Pressure* | psi | 504 | > 600 | > 550 | 540 | Ultimate Tensile Strength* | MPa | 20 | > 20 | > 17 | 22 | Ultimate Elongation* | % | 500 | > 1300 | > 1100 | 1275 | Thermal Stability** @ 200°C | min | 20 | > 80 | > 78 | 19 | Shrinkage** | % | < 3 | 1.88 | 1.65 | 1.30 |
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Note: Based on SDR 11 black pipes |
* | – Requirement based on ASTM D3350 (adopted as old standard PNS 55) |
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– Requirement based on ISO 4427 (adopted as new standard PNS ISO 4427) |
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Pipes after burst test. Notice that the pipe below didn’t burst at the joint (arrow) but at a point (encircled) between the joint and the tip of the sample. The butt-fused joint is actually stronger than the pipe; one of the advantages of PE pipes. |
