Corrugated polyethylene pipe used in mining applications, their compliance with specifications and anticipated design life

 

Papers # 2016 Berlin

Samples of polyethylene pipe supplied to mining projects throughout the Americas were selected and tested for compliance with existing ASTM specifications. Estimated service life of these pipe products in mining applications are made based on the laboratory tests required in the ASTM specifications. Anticipated performance requirements are considered in the design life predictions. The quality of the tested pipe varied widely.

Mining applications may be the most structurally demanding, chemically aggressive, and thermally extreme for thermoplastic pipe. In many cases, thermoplastic pipe, particularly polyethylene pipe, is the only material that can survive in this environment and installation conditions. Fill heights in excess of 200 meters are common, and chemicals include sulfuric acid or sodium cyanide, depending on the metal being extracted. Deflections in excess of 20% are not uncommon and widely accepted, resulting in high wall, long-term strains not typically permitted in civil construction.

Pipe samples collected from various mining projects throughout the Americas and United Kingdom were tested at Texas Research International (TRI) for conformance with existing ASTM mining pipe specifications. Predicted design lifetimes under the anticipated loads and environmental conditions are proposed, based on pipe quality as determined by these tests.

Related keywords : Mining; Quality; Stress crack resistance; Long term strain; Notched Constant Ligament Stress (NCLS); Oxidation Induction Time (OIT)..
Please note that the whole article content is available on PPCA website onlySource : 2016 Berlin


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