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MarkL

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Reply with quote  #1 
Just seen this today on CTC site, an interesting piece of Kit.
 https://www.youtube.com/watch?time_continue=244&v=vfyilRwAQHA&feature=emb_title
fburgos

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Reply with quote  #2 
How high can ultrasound go, 2140 has 80kHz sampling rate and I remember some go even higher, is this ultrasound?

Do we need a stud mount or like the ultrasound brands with their pionty things or flat magnet is enough?... Could this affect/benefit envelop techniques somehow?
MarkL

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Reply with quote  #3 
Ferdy, I think the advantage is it won't necessarily need to be stud mounted to get the data. I think its just offering a more reliable/repeatable way to get the high-frequency data.
Curran919

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Reply with quote  #4 
Game changer? Not so sure...

They say it can be used with 'every' vibe/ultrasound analyzer. Well sure, it is just a standard sheer-mode IEPE sensor. It just has a slightly higher resonant frequency than industrial sensors tend to have. The Emerson equivalent only has a 25kHz resonant frequency.

However, the last slide puts it correctly, it measures ultrasound and standard vibe frequencies simultaneously. There aren't many analyzers who are going to give the 90-128kS/s required to collect vibe and ultrasound at the same time. So you can either measure standard vibe (still linear up to 25kHz), or you can hook it up to a ultrasound meter that (correct me if I'm wrong) tend to not have an ADC converter before evaluating the waveform into a single value. Sure, there is lots of custom hardware (e.g. NI) that can do both simultaneous, but most (all?) handheld analyzers will not measure them simultaneously.

And yeah, I assume you have to have that stud mount to keep the resonance frequency around 44kHz.
Walt Strong

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Reply with quote  #5 
I have deconstructed SDT ultrasound contact and airborne sensors and read/searched a bit about them and others. The ultrasound sensor is "generally" not constructed like an accelerometer. They both have a piezo crystal, but the ultrasound sensor does not have a seismic mass attached. The ultrasound sensor can be used with a hand-held probe, but the HF accelerometer cannot. The HF accelerometer can be calibrated to a reference and with physical units, but the UT sensor cannot or is not. I read an article that when others had tried to use a very high frequency accelerometer as an ultrasound sensor the results were not good. No doubt that CTC has a good quality HF accelerometer, but do they have test data to support its use in place of an ultrasound sensor and meter. I look forward to seeing such information! Please buy one and rigorously test it, and then report your findings.

Walt
fburgos

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Reply with quote  #6 
As I understand ultrasound sensors have different construction, they are resonant sensors... something resonates at a tuned frequency and exite the piezo... so i've heard

could this have both things integrated?

some time ago read about SPM instruments and they have a specially tuned sensor for shockpulse method, now they have a duotech accelerometers a combination of vibration and shockpulse, could this CTC UEB330 do something similar.
OLi

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Reply with quote  #7 
In my book a ultrasound sensor is tuned to be resonant at or above 40kHz (the piezo) SPM eventually made a double sensor but that is made out of 2 sensor modules a normal and one with resoance at 23kHz or whatever it was. SKF many years ago had a SEE sensor that was sky hi (with magnet foot). So you need a demodulator thingy built in or added to be able to use the ultrasound part in a normal instrument I think. Calibration problem may be connected to the use of sensor resonance, amplitude may vary..... Generating a stable signal at 40+kHz is not that fun either.
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Curran919

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Reply with quote  #8 
Not being too familiar with ultrasound sensors, I can imagine them being with or without seismic mass. You need the seismic mass to have the resonant frequency. Without and it basically turns into an acoustic emissions sensor. As Walt says, I can definitely see massive practical implications between the two.

The Duotech has a single transducer as it only has a 2-pol connector. @Oli, I'm surprised that they would have made one previously that would have two separate transducers in one housing. What would be the point? Why can't you take standard vibration measurements from the high-freq sensor?
OLi

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Reply with quote  #9 

For a long time it was required 2 separate sensors as they could not convince themselves that you either could get a normal set of sensor data from a Shock pulse sensor, that I proven at least to my self and IRL is no problem or the other way around. Are you sure you get the "true" Shock pulse analysis from the 2 pin sensor? They have in part seen the light and added normal vibration analysis. Quite "recent" that is within some years the sensor for on-line was a #new" double thingy if you wanted true shock pulse. It was a stupid internal principle discussion I think.

You can have it with a 4-pin connector. https://extranet.spminstrument.se/Documents/Downloads/Support/TD-Sheets/TD304B.pdf

Normally the Shock pulse signal was treated from a bare piezo element in a std. compression configuration  giving a 60pC/g accel sensor when used in charge mode and more or less used in voltage mode in OEM mode and in later versions with filtering included prohibiting the use as std accel.
So maybe they now found that a std accel can be used for the same purpose, about time.
In my book everything have a resonance including sensor piezo elements of whatever shape or what you call them acoustic emission or not, they all have mass, seismic or not and behave pretty much the same you just need to adjust the freq. scale of your plot.


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fburgos

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Reply with quote  #10 
I have a hard time following grownups talk, so there's no way I can use this as airborne ultrasound with a vibration box, even if the box can go 80khz right
fburgos

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Reply with quote  #11 
Saw this on LinkedIn

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jpeg image_ee9d59a7-5fee-4748-bc3d-82fa71d4cae620200406_134732.jpg (186.21 KB, 12 views)

MarkL

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Reply with quote  #12 
I saw that image on the video presentation I posted originally, I think they are arguing they're design is more robust than the way the traditional contact Ultrasound sensors are constructed.



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