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Re: [MW:15419] Procedue for repairing cracks in base mental

By Materials & Welding
Cracks are said to be sharp in the end and more stress concentration is supposed to be in the weld ends -This concentrated stress is the basic reason for further development of the crack in the longitudinal direction. 

In some cases if the crack is allowed and with in the limit - to avoid further development of cracks small drilling carried  out on the tip of the crack

After drilling as there is no sharp edge of the crack - no more stress concentrations at the crack and chances of further cracking is avoided. Hope this technology can be used in the structural code. More details can be seen in AWS welding guide 

These drills are called as self ending drills. 

Even in some old car front wind shield glass we can see such small drills at the end of cracks- to avoid further development of the cracks. 

WISH TO KNOW MORE ON THIS PL - MORE AND BETTER COMMENTS REQUESTED.

On Fri, Sep 28, 2012 at 1:03 PM, mukesh.chaudhari <mukesh.chaudhari@orientalindia.net> wrote:

Dear expert,

Is it required to do drilling at both the end of crack which is identified in parent mental?

 

Regards,

Mukesh chaudhari

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