Forum Technical Discussions      Re: NDT gas distribution mains Posted by: sreeram srinivas , E-mail: Address, on January 09, 2009 at 02:50 : In Reply to: NDT gas distribution mains posted by : youri , E-mail: Address, on December 22, 2008 at 11:21 : ----------- Start Original Message ----------- : At the moment I am conducting a literature survey of available NDT techniques for steel gas distribution mains. These mains suffer from general corrosion, pitting corrosion and cracks. : On the internet and in literature I find several NDT methods, but it is unclear to me which are the most suitable. : Possible options are : Remote Field Eddy Current : Ultrasonic Phased Array : Magnetic Flux leakage : Guided Wave Inspection : However, I don't know what can be used best. For example Remote Field and Ultrasonic Phased array seem to have the same capabilities : Can someone explain what the advantages and disadvantages of above techniques are? : Thanks in advance! ------------ End Original Message ------------ Eddy current is used for small thickness pipes say below 5 mm. Most of the burried pipelines i.e. gas distribution lines have thickness above 6 mm unless one is doing a precision engineering to save costs. the preferred NDT for burried pipelines are Ultrasoni tests using intelligent pigs, which is a costly exercise done once in 5 yrs on average and is based on regulatory guidelines in respective countries. Follow Ups: Post a Followup: Name: E-Mail: Subject: Comments: ----------- Start Original Message ----------- : : At the moment I am conducting a literature survey of available NDT techniques for steel gas distribution mains. These mains suffer from general corrosion, pitting corrosion and cracks. : : On the internet and in literature I find several NDT methods, but it is unclear to me which are the most suitable. : : Possible options are : : Remote Field Eddy Current : : Ultrasonic Phased Array : : Magnetic Flux leakage : : Guided Wave Inspection : : However, I don't know what can be used best. For example Remote Field and Ultrasonic Phased array seem to have the same capabilities : : Can someone explain what the advantages and disadvantages of above techniques are? : : Thanks in advance! : Eddy current is used for small thickness pipes say below 5 mm. Most of the burried pipelines i.e. gas distribution lines have thickness above 6 mm unless one is doing a precision engineering to save costs. the preferred NDT for burried pipelines are Ultrasoni tests using intelligent pigs, which is a costly exercise done once in 5 yrs on average and is based on regulatory guidelines in respective countries. ------------ End Original Message ------------ Optional Link URL: Example: "http://www....html". Alternative write "http://www.ndt.net/wshop/attach/filename.htm" if you transfered a filename.htm via FTP Page Title: is important! Optional Image URL: http://www....gif Attention! Please click the button only once. This may take a moment to process Forum Technical Discussions Help