Line pipe, brittle fracture

Erosion Similar to abrasion cutting in ductile metal fracture (of brittle material) very small chips or particles (e.g., impellers, propellers, fans) Reduce fluid velocity to eliminate turbulence select harder alloy (high chromium) hard coatings such as cement lined pipe, rubber lining... 

In the long-term and under stress PE exhibits slow crack and brittle fracture in non-aggressive environments (e.g., air and water). This is of particular importance because PE is used extensively in applications that demand long-term durability (cable, pipe, landfill linings, geotextiles). At ambient temperature for high-quality grades the transition to brittle failure will occur after many years under stress. 

Several polyolefin field samples observed to have a brittle type of failure were examined. The failures were exhumed from service lines providing residential and commercial potable water. Optical Microscopy of the inner surface and fracture face was performed. Oxidation Induction Time (OIT) was performed in general accordance with ISO 11357-6-2002 (E) (8) at 200 °C from the inner and mid walls of the pipe specimens. Micro-attenuated total reflection Fourier Transform Infrared Spectroscopy (micro-ATR) was also performed on the inner surface and the fracture face. 

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