The objectives of this project were to: (1) examine known techniques of evaluating coating quality on buried pipe; (2) select one or more of these methods for in-situ testing; (3) develop a field test procedure that a corrosion technician can follow using equipment typically at his or her disposal; and (4) evaluate the feasibility of using this procedure both before and after the bored pipe is tied in. Two methods - coating conductance and current requirements - were tested on epoxy-coated pipe samples which were back filled with soil having a different resistivities. Both test methods proved ...
The objectives of this project were to: (1) examine known techniques of evaluating coating quality on buried pipe; (2) select one or more of these methods for in-situ testing; (3) develop a field test procedure that a corrosion technician can follow using equipment typically at his or her disposal; and (4) evaluate the feasibility of using this procedure both before and after the bored pipe is tied in. Two methods - coating conductance and current requirements - were tested on epoxy-coated pipe samples which were back filled with soil having a different resistivities. Both test methods proved successful; therefore, a field test procedure was developed that incorporates both. However, this procedure cannot be used when the pipe is tied-in because of accuracy limitations of existing current measurement instruments (unless the pipe is tied-in using isolating fittings). Includes spreadsheets to aid the assessment calculations and associated examples.