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Seek NDT tools : Crack detection with Red and white paint

Seek NDT tools : Crack detection with Red and white paint

Seek NDT tools : Crack detection with Red and white paint

I would like to know how I can obtain the tools for crack detection on metal surface with "paint" method. Someone tells me that there is a special tool which consists of red and white paints. After applying the two paints, the cracks will be "stained" red. Then, it is easy to see a red crack on the white surface. Does anybody provide me this information? Anyone knows this product?
Thank you very much!  

RE: Seek NDT tools : Crack detection with Red and white paint

This method is called Liquid penetrant

Here is the procedure:


Test procedure for inspecting welds and castings for cracks and pores using liquid penetrant.

Dynaflux, Inc. Cleaner CNF315
Dynaflux, Inc. Penetrant PHF315
Dynaflux, Inc. Developer DNF315


1.1.    CLEAN
1.1.1.    Use cleaner to pre-clean before testing.
1.1.2.    Apply a wet film to the part, allowing for adequate solvent time, and wipe clean with cotton clothe.
1.1.3.    Repeat until clean.  
1.1.4.    Allow part to dry.

1.2.1.    Spray penetrant onto the area to be examined, wetting the surface well.
1.2.2.    Allow 1 to 30 minutes before removing the excess penetrant. (Depend upon the crack size and contamination.  
1.2.3.    Remove the excessive penetrant, spray cleaner on a clean cloth and wipe surface.

1.3.    DEVELOP
1.3.1.    Thoroughly shake until the agitator clicks against the bottom and sides of the can.
1.3.2.    Spray a thin even coat on the suspected area.  
1.3.3.    Allow a developing time of 5 to 15 minutes, then inspect.  Red lines indicate a crack and red dots indicate mark pores.

Hope this helps, Rich

RE: Seek NDT tools : Crack detection with Red and white paint

You can visit http://www.cnde.iastate.edu/ncce/PT_CC/toc.html for an introduction to Penetrant Testing.  If you need to learn how to apply the PT process and gain certification please visit www.brighttechnical.com or contact me.

William E. Blum
Managing Director
Bright Technical Services Inc.
USA 1-817-274-1262
Fax/Voice Mail 1-435-417-3992
Sweden 46-42-14 39 99

RE: Seek NDT tools : Crack detection with Red and white paint

Don't be fooled! There are many brands of liquid penetrant out there. Sounds like someone is pushing the Dynaflux.

RE: Seek NDT tools : Crack detection with Red and white paint

No,I am not pushing Dynaflux, It is just what I had on my handy at my desk when I posted this. I just copied one of the procedures from my files and posted. Rich

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