Patent ID: 7069772
Filing Date: 2006-07-04
Classification: G01N

Abstract:
1. A method for assessing the life expectancy of a polymer lined pipe which transports fluids, comprising the steps of: positioning pre-aged polymer witness coupons in said polymer lined pipe, each of said pre-aged polymer witness coupons being made of the same material as a polymer in said polymer lined pipe, and each having a molecular weight, which can be the same or different for each pre-aged polymer witness coupon, which is less than an initial value for said polymer in said polymer lined pipe and more than a threshold replacement value for said polymer in said polymer lined pipe; determining an equilibrium molecular weight for said polymer based on changes in the molecular weight of said pre-aged polymer witness coupons over time; and comparing the equilibrium molecular weight to said threshold replacement value, and, based on the comparison determining whether