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View Full Version : X-raying Keelbolts



Oyvind Snibsoer
03-17-2003, 02:08 PM
The old thread at http://media5.hypernet.com/cgi-bin/UBB/ultimatebb.cgi?ubb=get_topic&f=1&t=006396&p= had gone a little off-topic so I figured I'd better make a new one.

I spoke to an experienced NDT inspector, i.e. Non-Destructive Testing (of metal constructions) about this a few days ago. He'd recently been involved in some X-ray work on a barque, the "Statsraad Lehmkuhl" which sails out of my home town. This is a steel hull with wooden decks etc.

He said that the problem with wood is that it is much too radioactive for X-rays. Simply put, the radiation from the wood will "smear" the photographic film used, making the pictures worthless. I believe he said that other inspection methods, such as ultrasound scanning, were also pretty worthless when there was wood in the vicinity of the steel. They eventually had to remove parts of the wooden deck to reveal severe rusting underneath.

Bottom line: You may as well pull'em.

[ 03-17-2003, 03:17 PM: Message edited by: Oyvind Snibsoer ]

Andreas Jordahl Rhude
03-17-2003, 03:52 PM
The US Department of Agriculture Forest Products Laboratory at Madison, Wisconsin has done sme type of X-Ray or cat scan or something??? of wooden ships to locate internal decay, etc... They did some experimental studies using that method on the USS Constitution "old Ironsides." I know someone at the FPL wrote a research paper on the topic. Maybe it can be found at the FPL website. They are part of the Forest Service.