Thermal ageing of PE 100 pipes for accelerated lifetime prediction under service conditions
It is widely accepted that the maximum lifetime of pipes made from bimodal HDPE types have reached a stage of development at which the service lifetime of the material is limited only by its resistance against thermal aging. The time until this degradation starts depends mainly on the stabilization package, the applied temperature, the oxygen concentration and the type and the flow rate of the media. However, a simple and fast method of determining the long term stability of HDPE pipes under service conditions is desirable. The resistance to thermal degradation was studied on pipes made from a PE 100 resin containing a usual antioxidant system in different concentrations. To simulate service conditions the heat ageing was performed under internal pressure with circulating or stagnant water at elevated temperatures until brittle failures occurred. The progress in ageing was studied on samples taken from the installed pipes and changes in molecular structure and antioxidant concentration were determined. The activation energies were calculated using the Arrhenius equation as a function of the fracture times and compared with those obtained as a function of other parameters such as loss in OIT.
H.Vogt H-F.Enderle U.Schulte J.Hessel
Basell Polyolefine GmbH Hessel Ingenieurtechnik GmbH
国际会议
2009(Beijing) International Plastic Pipe Ezchange Conference(国际塑料管道交流会)
北京
英文
33,35-41
2009-11-01（万方平台首次上网日期，不代表论文的发表时间）