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Nukisen
10-12-2010, 05:23 AM
Hi all!
My first question will be regarding the basic of maintain a good gas arc weld.

For the first is there a table or a calculation formula to remain the optimal heat input for differnt materials, Steel, Stainles, Aluminium?

I do know how to calculate the heat input if I have the parameter and travelspeed.

Or there is a table for parameters regarding this materials or a calculation formula?

As this far I have done this from experience or by the wire recomendation. Sometimes there is no guideline values for the parameters recomended by the wirespecification.

Thanks
//Janne

jakeru
10-12-2010, 01:57 PM
Assuming you're talking about TIG welding, the Miller TIG welding calculator is an OK (although pretty basic) starting point:
http://www.millerwelds.com/resources/calculators/tig_amperage_calculator.php

Nukisen
10-13-2010, 12:41 AM
Thanks jakeru!
Yes I have seen this and late yesterday I did find basic parameters at Oxfords homepage.
So now I do have pdf tables about the parameters.

Anyone want some just pm me and give me an email to send them to.
Today I will follow a welder in our company to catch the travelspeeds he uses. This guy is from Poland and a real damn good welder. I think that you who are the best welders does have it in your blood.
//Janne

nisdaniel
12-31-2011, 05:45 AM
Hi Nukisen I would like to have acopy from your pdf if it is not too much to ask

thanks

Mascheal
01-02-2012, 12:42 PM
I have a question regarding the heat calculation. In my shop we are working on a new project, I operate a saw machine both long seam and roll out. The WPS gives parameters for saw with 3/32 and 5/32 wire. The volts, amps and travel speed are the same for both wire sizes. The calculation that they use does not take the wire size into consideration. The process works fine for the 3/32 wire but when using 5/32 wire, the weld looks like...bad. The wire that we use is LAC-M2 and 888 flux. I believe that the amp limits should be considerably higher for the 5/32 wire. This is true of other projects that we are doing and have completed, the amps are higher for the 5/32 size wire and working with the same type of material. My basic question is; is there a joules calculation that considers the wire size for sub-arc welding?

Josh Flynn
01-02-2012, 02:37 PM
The wire size is taken into account indirectly with the heat imput formula, larger wire = more amps / volts that are plugged into your formula. Depending on the code and other requirements a new pqr might need to be ran to change your parameters to meet the requirments of the larger wire.

Awelderiam
01-08-2012, 09:17 AM
The wire size is taken into account indirectly with the heat imput formula, larger wire = more amps / volts that are plugged into your formula. Depending on the code and other requirements a new pqr might need to be ran to change your parameters to meet the requirments of the larger wire.

Wire diameter change should be a seperate welding procedure, if welding under code. I would assume AWS D1.1 and ASME would read the same on this. Going from 3/32 to 5/32 is a huge change in heat input.......no way the same amps and wire/travel speed would be the same.

Josh Flynn
01-14-2012, 10:33 PM
Wire diameter change should be a seperate welding procedure, if welding under code. I would assume AWS D1.1 and ASME would read the same on this. Going from 3/32 to 5/32 is a huge change in heat input.......no way the same amps and wire/travel speed would be the same.

No you would not use the same amps/wire speed/ travle speed for differnet wire types( my previous post), you take the wire diameter size into accout with the heat input formula. If you were working to D1.1 you would need to run a new pqr for the differnet wire sizes, unless its GTAW and you can change the size filler wire by +-1/16 with no need to requal.