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[MW:647] Re: Hardness by Equotip

By Materials & Welding
Dear Venu,
 
Thanks for your reply.
Just I would like to know, whether this rebound principle is recognised in construction industry and being used else where or not.
 
I have studied in depth about this hardness tester and there are other models like UCS working on the principles of ultrasonics and third one is TIV. However, this rebound principle is well known to mechanical industry. Also, ASTM standard is available on digital hardness tester working with rebound principle.
 
Here, our dept is not allowing this type of hardness tester for hardness check at SEZ refinery construction. However, I am trying to convince HOD and other colleagues to introduce this tester. 
 
Any way, pl. note my personal mail id also and send mails. Convey our best wishes to all your family members.   
 
Regards,


T S Reddy
Mobile: 919998215568
India


----- Original Message ----
From: juttada venugopal <jamsvenu@gmail.com>
To: materials-welding@googlegroups.com
Sent: Sunday, 2 March, 2008 5:10:47 PM
Subject: [MW:644] Re: Hardness by Equotip

Dear Reddy,
 

Equotip is digital based, unlike Poldy which is mechanical based.

(1) This needs the surface to be smooth, so that rebound shall be proper for its analysis.

(2) The rebound ball is few grams so thickness of the part shall not be an essential criterion. There is facility for angle setting in this instrument, 0deg  i.e., is hitting the targets vertically down, and other angle hitting facility exists

 (3) Equotip is supplied with thick round calibration block, valves on it are mentioned to match with for calibration purpose.

 (4) These are commonly used in maintenance sections of the plants. It only gives the valves of the hardness, so hope no implications of restriction of any codes prevails.  

 

Hope I have answered your questions.

 

Regards,
 
Venu
Singapore
================================================================
On Sun, Mar 2, 2008 at 5:26 PM, tamma reddy <tsr_52@yahoo.co.in> wrote:
Dear Friends,
 
Can any one through light on the following queries of digital hardness tester (Eqotip/TIME Group TH 160, HLN-11A/Krautkramer etc.)
 
1. Can weld joint hardness check up with rebound test principle
2. what is the minimum thickness of test specimen required for hardness check with above equipment (working on Rebound principle)
3. What are the calibration requirement of above instruments
4. Are they supported by any project construction codes/ standards
 
Regards,

T S Reddy
Jamnagar

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