where expertise comes together - since 1996 -

The Largest Open Access Portal of Nondestructive Testing (NDT)

Conference Proceedings, Articles, News, Exhibition, Forum, Network and more

where expertise comes together
- since 1996 -

Vallen-Systeme GmbH
The Acoustic Emission Company! Since 1987 Vallen stands for competence and continuity in AE and for reliable business cooperation and support.
4824 views
Technical Discussions
bhogesh
bhogesh
06:37 Dec-14-2015
1MHz and 2 MHz probe difference

Sir I was inspected the 2 mtrs length shaft in axial direction with the 2 MHz 24 dia probe observed peak at 1024 mm with no loss of back wall echo. And same done with 1 MHz probe result is same. But gain taken higher than the 2MHz probe. What is the solution to find out the intermediate peak which shaft is installed.

 
 Reply 
 
Anmol Birring
Consultant,
Birring NDE Center, Inc., USA, Joined Aug 2011, 747

Anmol Birring

Consultant,
Birring NDE Center, Inc.,
USA,
Joined Aug 2011
747
09:13 Dec-14-2015
Re: 1MHz and 2 MHz probe difference
In Reply to bhogesh at 06:37 Dec-14-2015 (Opening).

Reduce the Rep rate (PRF) of the instrument.

 
 Reply 
 
bhogesh
bhogesh
11:43 Dec-14-2015
Re: 1MHz and 2 MHz probe difference
In Reply to Anmol Birring at 09:13 Dec-14-2015 .

Sir thanks for your reply. I was reduced prf but its showing same problem.

 
 Reply 
 
Anmol Birring
Consultant,
Birring NDE Center, Inc., USA, Joined Aug 2011, 747

Anmol Birring

Consultant,
Birring NDE Center, Inc.,
USA,
Joined Aug 2011
747
12:17 Dec-14-2015
Re: 1MHz and 2 MHz probe difference
In Reply to bhogesh at 11:43 Dec-14-2015 .

What is the rep rate ?

 
 Reply 
 
Wieslaw Bicz
Engineering,
PBP Optel sp. z o.o., Poland, Joined Feb 2009, 259

Wieslaw Bicz

Engineering,
PBP Optel sp. z o.o.,
Poland,
Joined Feb 2009
259
12:42 Dec-14-2015
Re: 1MHz and 2 MHz probe difference
In Reply to bhogesh at 06:37 Dec-14-2015 (Opening).

What was the diameter of the shaft?

 
 Reply 
 
P V SASTRY
R & D, NDT tecniques metallurgy
TAKEN VRS FROM THE POSITION OF SR. DEPUTY GENERAL MANAGER BHEL CORPORATE R&D, India, Joined Jan 2003, 195

P V SASTRY

R & D, NDT tecniques metallurgy
TAKEN VRS FROM THE POSITION OF SR. DEPUTY GENERAL MANAGER BHEL CORPORATE R&D,
India,
Joined Jan 2003
195
15:24 Dec-14-2015
Re: 1MHz and 2 MHz probe difference
In Reply to bhogesh at 06:37 Dec-14-2015 (Opening).


Please give not only the shaft diameter and material but the following additional information.

What is the function of the shaft.

Is it a new shaft or used one.

If it is used Please tell if any disc or bearing etc was mounted at the location from where the peak is coming ( 1024 mm) . Is there any disc/bearing etc mounted now on the shaft.

Have you verified visually at the location of the peak if there is any notch/scratch etc. ( Since you are performing the axial test the amplification/gain must be very high and even scratches of reasonable depth can give indications)

Finally Please tell if you have touched the location from where the peak is coming ( 1024mm) with oiled fingers while continuing the UT. If so what is the response of the peak while you are touching.

If you have not done the above experiment please do it now with both frequencies and observe the response of the peak and inform us. Also you may use 4 MHz probe also, if it is penetrating.

Best wishes

P V SASTRY

1
 
 Reply 
 
Godfrey Hands
Consultant,
PRI Nadcap, United Kingdom, Joined Nov 1998, 303

Godfrey Hands

Consultant,
PRI Nadcap,
United Kingdom,
Joined Nov 1998
303
17:55 Dec-14-2015
Re: 1MHz and 2 MHz probe difference
In Reply to P V SASTRY at 15:24 Dec-14-2015 .

Regarding the spurious signal at 1024mm.
Can you check that there is not a diameter reduction on the outer end of the shaft at just over 500mm or around 750mm.
If there is, it could well be a mode conversion from the diameter reduction. It would show up with less amplitude at lower frequency because of a narrower beam profile.
If there is a diameter reduction, do the math. L/L against L/T or T/T, and compare to 1024mm.

Godfrey Hands

 
 Reply 
 
mansoor ali
India, Joined Jan 2015, 5

mansoor ali

India,
Joined Jan 2015
5
19:11 Dec-14-2015
Re: 1MHz and 2 MHz probe difference
In Reply to Anmol Birring at 12:17 Dec-14-2015 .

Sir,please explain about PRF( rep rate)

 
 Reply 
 
mark
mark
19:26 Dec-14-2015
Re: 1MHz and 2 MHz probe difference
In Reply to Godfrey Hands at 17:55 Dec-14-2015 .

if you have access to around area of 1024 mm,you could also check with shear wave angle beam probes to see there is defect or not.

 
 Reply 
 
bhogesh
bhogesh
04:11 Dec-15-2015
Re: 1MHz and 2 MHz probe difference
In Reply to Anmol Birring at 09:13 Dec-14-2015 .

Sir so thank full about your information. It was a installed with conveyor pulley new shaft. It was a non drive pulley. There is a no chance to observe the where we are getting (1024) peak. There it is covered with pulley.inspection possible in axial direction. And I was inspected both sides observed peak at same length.

 
 Reply 
 
bhogesh
bhogesh
04:16 Dec-15-2015
Re: 1MHz and 2 MHz probe difference
In Reply to Anmol Birring at 12:17 Dec-14-2015 .

175 low

 
 Reply 
 
Manuel Haces
Director, - Wire rope inspection
Haces Inspección del Noreste and Wire Rope Inspection, Mexico, Joined Jun 2002, 122

Manuel Haces

Director, - Wire rope inspection
Haces Inspección del Noreste and Wire Rope Inspection,
Mexico,
Joined Jun 2002
122
20:25 Dec-15-2015
Re: 1MHz and 2 MHz probe difference
In Reply to bhogesh at 04:11 Dec-15-2015 .

Send a sketch with dimensions of the conveyour pulley in order to clarify the origin of signal. We have similar responses from time to time. Regards.

1
 
 Reply 
 
massimo carminati
Consultant, AUT specialist
IMG Ultrasuoni Srl, Italy, Joined Apr 2007, 691

massimo carminati

Consultant, AUT specialist
IMG Ultrasuoni Srl,
Italy,
Joined Apr 2007
691
20:30 Dec-15-2015
Re: 1MHz and 2 MHz probe difference
In Reply to bhogesh at 04:16 Dec-15-2015 .

175 Hz on a 2 meter shaft is not low, particularly at 2 or 1 MHz...

 
 Reply 
 
Godfrey Hands
Consultant,
PRI Nadcap, United Kingdom, Joined Nov 1998, 303

Godfrey Hands

Consultant,
PRI Nadcap,
United Kingdom,
Joined Nov 1998
303
20:55 Dec-15-2015
Re: 1MHz and 2 MHz probe difference
In Reply to bhogesh at 04:11 Dec-15-2015 .

From your description, it could be some ultrasound leaking from the shaft into the pully and being reflected from the far side of the pully.
The pully would need to be a tight fit on the shaft for that.
If the shaft is 2 metres long and the signal is at 1024 from both sides, is the pully 2 x 24mm thick, that is 48mm thick where it mounts on the shaft?

Have you tried a surface wave probe looking "under" the pully mounted on the shaft? If you can get the front of a surface wave probe in contact with the pully, you should be able to scan all around the circumference. If there are any signals, do they vary around the circumference, or is the amplitude constant? If it is a constant amplitude, this suggests some physical or geometrical feature, whilst an irregular amplitude suggests some from of discontinuity.

Godfrey

 
 Reply 
 
bhogesh
bhogesh
03:48 Dec-16-2015
Re: 1MHz and 2 MHz probe difference
In Reply to massimo carminati at 20:30 Dec-15-2015 .

In USM instrument showing minimum prf 175.

 
 Reply 
 
bhogesh
bhogesh
09:53 Dec-18-2015
Re: 1MHz and 2 MHz probe difference
In Reply to Godfrey Hands at 20:55 Dec-15-2015 .

zoom image


pulley drawing

zoom image


drawing length

sir attaching pulley drawing and length of the drawing. Please verify the drawing and guide me the solution.
 
 Reply 
 
P V SASTRY
R & D, NDT tecniques metallurgy
TAKEN VRS FROM THE POSITION OF SR. DEPUTY GENERAL MANAGER BHEL CORPORATE R&D, India, Joined Jan 2003, 195

P V SASTRY

R & D, NDT tecniques metallurgy
TAKEN VRS FROM THE POSITION OF SR. DEPUTY GENERAL MANAGER BHEL CORPORATE R&D,
India,
Joined Jan 2003
195
19:43 Dec-18-2015
Re: 1MHz and 2 MHz probe difference
In Reply to bhogesh at 09:53 Dec-18-2015 .


It looks that you are getting the peak/echo from the central disc.

The drawing is not clear regarding the thickness and location of the central disc. You have to give the thickness of the disc and also clarify how it was fixed on the shaft. ( From the so called note mentioned but not given here)

Was is shrunk fit or welded.

From the peak/echo location it looks that the the disc is about 15 to 18 mm width and is welded. You may be getting the echo from the weld. (weld located on the farther side of the disc from your probing face)

You must be getting the echo all around when you move the probe along the periphery of the face of the shaft and the echo must be some what reducing ( if not disappearing) when you take the probe nearer to the center of the face. Here I am referring to 2 MHz probe only.

Please try with a 4 MHz 20/24 mm dia probe you may not get the echo with this probe or at least when you move slightly towards the center of the face.

Best wishes

P V SASTRY

 
 Reply 
 
Manuel Haces
Director, - Wire rope inspection
Haces Inspección del Noreste and Wire Rope Inspection, Mexico, Joined Jun 2002, 122

Manuel Haces

Director, - Wire rope inspection
Haces Inspección del Noreste and Wire Rope Inspection,
Mexico,
Joined Jun 2002
122
20:25 Dec-18-2015
Re: 1MHz and 2 MHz probe difference
In Reply to P V SASTRY at 19:43 Dec-18-2015 .

Reflection from the disc. Agree with Mr. Sastry. Regards.

 
 Reply 
 
aiph
Armenia, Joined Nov 2014, 174

aiph

Armenia,
Joined Nov 2014
174
04:52 Dec-19-2015
Re: 1MHz and 2 MHz probe difference
In Reply to bhogesh at 06:37 Dec-14-2015 (Opening).

do you carry out by manual or the automate machine? How do you make sure there is no loss of the back wall echo? what is your sensitivity when you inspect the forging? If the sensitivity is too high, you won't find the loss of the back wall echo when you do by manual. there is an indication without the loss of the back wall echo, how does it happen? Don't you know the energy conservation?

 
 Reply 
 
bhogesh
NDT Inspector,
Tata steel, India, Joined Dec 2015, 11

bhogesh

NDT Inspector,
Tata steel,
India,
Joined Dec 2015
11
13:28 Dec-19-2015
Re: 1MHz and 2 MHz probe difference
In Reply to aiph at 04:52 Dec-19-2015 .

It was carried out by manual. And at one position we are taken reference 80% Bach wall. But at middle peak is observed with no back wall loss.

 
 Reply 
 
massimo carminati
Consultant, AUT specialist
IMG Ultrasuoni Srl, Italy, Joined Apr 2007, 691

massimo carminati

Consultant, AUT specialist
IMG Ultrasuoni Srl,
Italy,
Joined Apr 2007
691
13:55 Dec-21-2015
Re: 1MHz and 2 MHz probe difference
In Reply to bhogesh at 13:28 Dec-19-2015 .

There is no other justification than the central plate for that indication (no mode converted can give an echo at that position).

 
 Reply 
 

Product Spotlight

Sci Aps Z-Series Portable Handheld Analysers

The world’s only handheld analyzer that measures carbon content in stainless (yes even L-grades),s
...
teels, and cast irons. Also accepted for low Si analysis for sulfidic corrosion analysis, and is widely used in the power industry for Cr analysis, for flow accelerated corrosion applications.
>

Combination of Digital Image Correlation and Thermographic Measurements

The combination of measuring results from the digital image correlation (ARAMIS, DIC) and temperat
...
ure measuring data from infrared cameras permits the simultaneous analysis of the thermal and mechanical behavior of test specimens in the materials and components testing field.
>

XRHRobotStar

In high volume industries like automotive the requirement for a hundred percent X-ray inspection c
...
reates a bottleneck in the production. The XRHRobotStar is a fully Automated Defect Recognition (ADR) capable robot-system that allows an ultra-fast in-line inspection.
>

GEKKO - Portable Phased Array Testing with TFM in Real-Time

The portable phased array testing system GEKKO provides 64 parallel test channels. On creating testi
...
ng parameters the operator is assisted by the CIVA software. Due to its modular set-up the GEKKO instrument is suitable for operators of all skill levels.
>

Share...
We use technical and analytics cookies to ensure that we will give you the best experience of our website - More Info
Accept
top
this is debug window