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"Wear It's At"

Volume 1 Issue 10

Friday, December 3, 1999

 

In This Issue

 

1. Welcome
2. Sponsorship/Directory
3. Porosity Test for Tubular Wires


1. Welcome


I want to wish all those who signed up for this newsletter, a warm welcome.  I also want to wish the new SPONSORS to the newsletter a warm welcome also.  Your support is highly valued.


2. Newsletter Sponsorship/Directory


I mentioned in past issues that I was considering a SPONSORSHIP to this newsletter.  I am pleased to announced that it has become a reality.  SPONSORSHIP is now available and can be accessed at http://www.cladtechnologies.com/directory/internet_services.htm . There are a number of options available including Web Page designs.  Up to 4 pages can be designed and will appear in the DIRECTORY section of my Web Site.  This is an excellent opportunity for companies and individuals to become a part of  the explosive media of the Internet.  The SPONSORSHIP also entitles one to a listing in my new DIRECTORY.  The DIRECTORY will be listing wear related entities such as, electrode manufacturers, distributors, fabrication  shops, OEMs, and Consultants.  The DIRECTORY can be accessed at http://www.cladtechnologies.com/directory . Please pass this information along to anyone you think might be interested.  It's a great opportunity to acquire new business and establish Internet presence.


3. Porosity Test for Tubular Wires


I have had a lot of response to the last Issue regarding the test for uneven fill in tubular wires.  There is nothing like these little tests to help you out of a problem and cut your detective time down.  In light of that response I thought I might share another test that comes in very handy to determine the extent of porosity produced by a tubular wire.  Let me first say that today's tubular wires are very well made and free of any moisture that ultimately leads to porosity.  But because of high humid conditions in some parts of the world, there is a possibility that wire left unattended and unused will pick up some moisture.  The porosity that occurs in a weld deposit often goes undetected because it is subsurface.  It may only rear its ugly head after the deposition of a number of layers.  And in the case of hardfacing wires, only a couple of layers is the norm and therefore presents a very real problem.  As we saw in the episode regarding hydrogen cracking, moisture can lead to some very critical situations.

The test is quite simple:

1.  Weave a bead of the suspect wire on a good test plate such as A36 or Mild Steel (1020).  The bead should be at least 10 times the wire diameter in width and perhaps as long as 6".  (The weaving helps bring out the porosity).
2.  Arc gouge the deposit on the very surface and inspect for holes.  Do not remove too much metal from the deposit, (perhaps about 15%). Inspect for porosity.
3.  If no porosity is seen after gouging, deposit another bead on top of the previous gouged bead and repeat the gouging and inspection of this new layer for porosity.  
4.  Repeat the processes (1 & 2) until you have built up at least 3 or 4 layers.  If no porosity occurs on the fourth layer, you can rest assured that the wire has not moisture or porosity producing elements.  

Incidentally, this test works for gas shielded, sub arc and open arc wires.

Hope this will add to your list of helpful hints.  Have a great day and a great weekend.

SPONSORS:
Bohler Thyssen Welding USA Inc.  http://www.btwusa.com 
is  a single source supplier for practical high quality electrodes, wires and fluxes
Sure Alloy Steel Corp
. http://www.surealloy.com  Wear control design, engineering, and fabrication with over forty years experience.


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