Some Recent Thermal Images from Marine Surveys

[Paul L]

Originally Posted by SuenosAzules

It would be the same (about $22.00 a foot). I do not charge extra for thermal imaging. It only helps me do a better job.

For that additional price I'm all over it

[kmacdonald]

Unfortunately the results among surveyors vary greatly. Sound science requires repeatability and that doesn't exist in the use of thermal imaging in marine surveys. It's a disservice to the seller and buyer. The seller could lose a sale due to an inaccurate interpretation and a buyer could pass on a good boat. Lazy surveyors use it in lew of a thorough inspection and as a wow factor. Ask 10 surveyors to evaluate a thermal image and you will get 10 different opinions. Another toy for a boy.

[kmacdonald]

As others have said, thermal imaging just shows surface temperature. What that represents is a guessing game.

[Steve Bean]

I have a suggestion for those with this equipment to improve their skills. Find some derelict boats that are about about to be destroyed and do the thermal imaging, then follow up with the Sawzall!

[fivecapes]

I've seen FLIRs used to detect big and small leaks in old buildings. The before and after images are stark.

For FLIRs to properly show enough delta T the boat should probably be recently hauled. It's just another tool to draw your attention to potential problem spots.

If nothing else, I can always use it as a bargaining chip.

Moisture meters, now that's a black art.

[slug]

Originally Posted by UNCIVILIZED

Some really interesting stuff, to be sure. It makes me curious to play with some of the cameras & other hardware, as the last time I had the chance was a couple of decades back. And the gear was optimized for other uses (firefighting).

Have you done much work imaging spars? Carbon fiber, & wood, specifically. As I'm curious what kinds of things can be determined, & what can't. Like rot eating a wooden spar from the inside, for example. That could be a handy one. Ditto on detecting damage in carbon spars.

Not to impose, but I'm sure that lots of folks besides me would love to see more images, along with their 'captions'. Ditto on what you find to be the most effective techniques for spotting issues. Meaning things that you do in order to maximize what the camera can see. Tricks of the trade as it were.

Thanks for sharing this.

The non destructive testing that I see performed on carbon masts is ultrasonic

In the perfect world the spar or structure is tested when new to create s baseline profile for future tests

http://www.marineresults.com/survey/ultrasonic-testing/

https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/295030/carbon_masts_and_spars_guidance.pdf

[Checkswrecks]

Originally Posted by kmacdonald

As others have said, thermal imaging just shows surface temperature. What that represents is a guessing game.

That's under-stating the same as saying that sailing is just going out on the water and putting up some cloth to let wind push the boat.

I've worked with a lot of bonded composites and there is a HUGE difference between an inspector experienced in the use of IR scans, one making an educated guess based on training, and people using the tool with minimal experience or training. The first two will use the results of the scans to know where to look closer and where to not waste time.

I was working with a guy looking at a rotor blade and there was a minor color feature in the plies which caught his eye that had not registered to me. He already knew what was going on because of his training and experience so to show me he brought out a drawing of the part and a heat gun then lightly warmed the surface for a few seconds. Because the interior features act as a heat sink, the next scans were like having x-ray vision for the cross section. It turned out that one of the plies had been doubled or tripled, concentrating stress at the edge of the steps in plies we could not see. That was the point he used ultrasound and was able to count the number of plies and where each ended. The very expensive rotor blade could have failed through a very shortened fatigue life and was scrapped.

In the field, we would try to use IR just after dawn or sunset, because the effect of rapidly changing temperature on the surface versus the internal heat sinking characteristics was very much like using the inspectors' heat gun.

[kmacdonald]

Originally Posted by Checkswrecks

That's under-stating the same as saying that sailing is just going out on the water and putting up some cloth to let wind push the boat.

I've worked with a lot of bonded composites and there is a HUGE difference between an inspector experienced in the use of IR scans, one making an educated guess based on training, and people using the tool with minimal experience or training. The first two will use the results of the scans to know where to look closer and where to not waste time.

I was working with a guy looking at a rotor blade and there was a minor color feature in the plies which caught his eye that had not registered to me. He already knew what was going on because of his training and experience so to show me he brought out a drawing of the part and a heat gun then lightly warmed the surface for a few seconds. Because the interior features act as a heat sink, the next scans were like having x-ray vision for the cross section. It turned out that one of the plies had been doubled or tripled, concentrating stress at the edge of the steps in plies we could not see. That was the point he used ultrasound and was able to count the number of plies and where each ended. The very expensive rotor blade could have failed through a very shortened fatigue life and was scrapped.

In the field, we would try to use IR just after dawn or sunset, because the effect of rapidly changing temperature on the surface versus the internal heat sinking characteristics was very much like using the inspectors' heat gun.

And that's exactly why they are so dangerous in the hand of the unskilled marine surveyors. Its comical to listen to the BS they spew about "seeing thru the surface". They take a few shots to cut and paste in a report. No further investigation is done after the untrained analysis. In a lot if cases an entire report is based on a 20 minute IR shoot.
The technology wasn't developed for this purpose but may have some applications in the marine survey business. The FBN marine surveyor isn't one of them.

[slug]

Thermal imagining of marine electrical installations is very worthwhile

[Eigenvector]

"And that's exactly why they are so dangerous in the hand of the unskilled..............."


That's why the qualifications are governed by ASNT.


https://www.asnt.org/MajorSiteSectio...ations/IR.aspx

[Checkswrecks]

Originally Posted by kmacdonald

And that's exactly why they are so dangerous in the hand of the unskilled marine surveyors. Its comical to listen to the BS they spew about "seeing thru the surface". They take a few shots to cut and paste in a report. No further investigation is done after the untrained analysis. In a lot if cases an entire report is based on a 20 minute IR shoot.
The technology wasn't developed for this purpose but may have some applications in the marine survey business. The FBN marine surveyor isn't one of them.

Your use of the key word "unskilled" said it all and why asking for certifications and references is so important, as Eigenvector notes.

slug mentioned the use on electrical installations and that is a lot more conducive to anybody being able to pick out a problem. I've used it for years to pick out loose and corroded connections and it will also quickly show overloaded ones.

The following is an IR photo of the top of a 787 Li-ion battery from when we were doing tests in a UL lab to simulate starting one of the airplane engines. It's pretty easy to see that cell 5 had a terminal getting much hotter than anything else, and sure enough it was hot enough to melt the separator between the anode and cathode layers within the cell, leading to thermal runaway.
https://photos.smugmug.com/photos/i-...3qXjPc5-X3.jpg

[Flightime]

How do I get you or a surveyor that you know of similar quality to do a survey for me in BVI after September 1st?

It’s nice to see someone good at their job and enjoys doing it. I have much respect for that. Cheers mate!