• Thomas R. Hay, Ph.D., P.E

Acoustic Emission Testing of Fiberglass Reinforced Plastic FRP Tanks

Updated: Feb 27, 2020

TECHKNOWSERV CORP. (TKS) is a leading supplier of fiberglass tank acoustic emission testing on new and in-service fiberglass reinforced plastic tanks. Acoustic emission testing (AET) is used to inspect newly fabricated tanks during hydrostatic testing and in-service testing typically in 5-year intervals. The object of acoustic emission testing of FRP tank are to find manufacturing and in-service defects that include delaminations, fiber breaks, matrix cracking, and fiber pullout. Acoustic emission testing in accordance with ASTM E1067-07: Standard Practice for Acoustic Emission of Fiberglass Reinforced Plastic Resin (FRP) Tanks/Vessels. ASTM 1067E is an advanced integrity test that quantifies the deterioration of reinforced plastic tanks.

The process required installation of acoustic emission sensors at different tank elevations and a calibration process that confirms the detectability. The total number of sensors depends on the acoustic properties of the tank and the number of critical areas to be monitored which may include known damage areas, stress concentration areas, and attachments like piping and flanges. The tank is progressively filled to 50%, 75%, 87% and 100% capacity. At each interval, the tank is acoustically isolated and sensors listen for acoustic emission activity. The acoustic emission data is analyzed determine how intensity and activity. The intensity and activity are measures of the severity of the defect in the fiberglass tank.