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 -

KARL DEUTSCH
INSTRUMENTS AND SYSTEMS FOR NON-DESTRUCTIVE TESTING OF MATERIALS.
1221 views
Technical Discussions
Yasu Ohgi
Yasu Ohgi
04:24 Feb-13-2000
Very Tight Cracks

Dear Sir.
I am an NDT engineer for machanical parts occupied Japanese company.
My problem is the method of detecting very tight and small cracks occured at the non ferrous casted parts edge.
The cracks are too tight to detect by PT, and it is hard to apply ET because of its lift-off characterization.
Someone who has a good idea, please imform me.
Regards.



    
 
 Reply 
 
Robert (Rocky) A. Day
Engineering
Milky Way Jewels, USA, Joined Nov 1998, 40

Robert (Rocky) A. Day

Engineering
Milky Way Jewels,
USA,
Joined Nov 1998
40
06:38 Feb-13-2000
Re: Very Tight Cracks
There are several things you can try. Tightly closed cracks are often a challenge for most NDT methods.

- Use a more sensitive penetrant, e.g. fluorescent.
- Not knowing your geometry I do not know if eddy current could be adapted but you might send samples for evaluation. I would be happy to look at them if you wish.
- Ultrasonics should be considered as well. Same geometry problem as eddy current. Again most vendors would be happy to look at samples.
- Try opening the crack by applying tension to the part in such a way the crack is opened. You can try cycling the tension while the penetrant dwells to see if you can work penetrant into the crack (this is sometimes called winking). This can also sometimes be done with heat.


: Dear Sir.
: I am an NDT engineer for machanical parts occupied Japanese company.
: My problem is the method of detecting very tight and small cracks occured at the non ferrous casted parts edge.
: The cracks are too tight to detect by PT, and it is hard to apply ET because of its lift-off characterization.
: Someone who has a good idea, please imform me.
: Regards.




    
 
 Reply 
 
Quan Zhang
Quan Zhang
08:52 Feb-14-2000
Re: Very Tight Cracks
Dear Yasu Ohgi:
What I suggest you do, contact maintainence base of big airline company, they are very experience to do PT on non ferous metal parts, you will win.
Regards.




    
 
 Reply 
 
M Daehling
Engineering, NDI Administrator
Bombardier Aerospace, USA, Joined Oct 1999, 5

M Daehling

Engineering, NDI Administrator
Bombardier Aerospace,
USA,
Joined Oct 1999
5
07:59 Feb-18-2000
Re: Very Tight Cracks
Dear Sir.

I found the following website that might interest you. Krypton Gas penetrant imaging might work in your application.
http://www.asnt.org/publications/materialseval/solution/decsolutions/decsolutions.htm

Good Luck

: Dear Sir.
: I am an NDT engineer for machanical parts occupied Japanese company.
: My problem is the method of detecting very tight and small cracks occured at the non ferrous casted parts edge.
: The cracks are too tight to detect by PT, and it is hard to apply ET because of its lift-off characterization.
: Someone who has a good idea, please imform me.
: Regards.




    
 
 Reply 
 
J. Mark Davis
Teacher, And Consultant
University of Ultrasonics, Birmingham, Alabama, USA, Joined Mar 2000, 85

J. Mark Davis

Teacher, And Consultant
University of Ultrasonics, Birmingham, Alabama,
USA,
Joined Mar 2000
85
00:58 Feb-24-2000
Re: Very Tight Cracks
Yasu,


Do you have access to the crack initiation side of the component? Have you considered ID or OD Creeping Waves?

I have successfully detected cracks at about 0.005" of an inch with a Creeping Wave.

What is the grain size of the component? Please check out the Advanced UT Flaw Sizing Handbook for a description of the Creeping Technology. It is in the NDT.net library.

J. Mark Davis

: Dear Sir.
: I am an NDT engineer for machanical parts occupied Japanese company.
: My problem is the method of detecting very tight and small cracks occured at the non ferrous casted parts edge.
: The cracks are too tight to detect by PT, and it is hard to apply ET because of its lift-off characterization.
: Someone who has a good idea, please imform me.
: Regards.




    
 
 Reply 
 

Product Spotlight

PROlineTOP Plug & Play Ultrasonic inspection device

As Plug & Play solution it units all control and operation elements in a small housing and therefo
...
re replaces the typical control cabinet...
>

NDTkit RT

NDTkit RT, TESTIA's Digital Radiography software The NDTkit product line software for X-ray analysi
...
s. NDTkit RT is a software benefiting from the Ultis kernel which is dedicated to radiographic image analysis. It offers a set of tools and filtering processes to assist RT operators in finding relevant flaws.
>

Ultrasonic tomograph for imaging of concrete structures А1040 MIRA

Applicable for concrete inspection allowing imaging of the internal structure of objects from conc
...
rete, reinforced concrete, different stones. The operation applies pulse-echo technique at one-side access to the object. The instrument is feasible for concrete inspection for searching conduct ducts, conduits, detection of foreign inclusions, holes, honeycombing, cracks and other concrete defects.
>

Cygnus 6+ PRO Multi-Mode Ultrasonic Thickness Gauge

The Cygnus 6+ PRO thickness gauge is the most advance gauge within the Cygnus range with key featu
...
res including: comprehensive data logging; A-scan and B-scan display; manual gain control; Bluetooth connectivity; and much more. With its unique dual display and three measuring modes (Multiple-Echo, Echo-Echo and Single-Echo), this surface thickness gauge offers maximum versatility for inspections.
>

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