I am having problems with my contact tips warping. The parameters that are being used are 30V, 300A. Is this a common problem or is there something I can change to correct this? Is it possible that the contact tips are of low quality and cannot tolerate the heat thatis generated. Would a change in cone (nozzle) style help correct this? Any information or suggestions would be appreciated.
Thanks For the Help,
Marc Brach
By -
Date 06-08-2000 18:45
Although I have never ran into this problem myself I will try to offer some advice. First check and make sure that the set back between the tip and the gas cup is correct. Also by warping do you mean that the tip is actually no longer straight? Or is the tip being worn out by wire drag. A common problem with wire welding tips is the wire "drags" on the outside of the tip hole enlarging it. Our welders run 1/16 FCAW dual shield and do wear quite a bit due to the stiffness of the wire and its reluctance to straighten out once its put on a roll.
Thank you for the reply. By warping I mean that the tip is actually bending and eventually (with the help of spatter) makes contact with the cup destroying both.
Is this in the spray mode (gas / wire dia.) and is the torch air or water cooled??
What filler ?/ Ni based alloys and others are hard on tips
Are the contact tips heavy duty or "normal service" ???
What is the arc time typically IE hand held applications / mechanized ?
We are using an 82/18 argon-co2 mix. Therefore I am not sure if it is a true spary transfer. The electrode we are using is Lincoln's 71M 1/16 dia. (FCAW dual shielded). The welding is done manually. What doesn't make sense is others that are doing similar jobs with the same settings are not having this problem. The guns are air cooled with about 35-45cfh setting for shielding gas. The shielding gas wouldn't cool the tip to enough make a difference would it?
By -
Date 06-13-2000 20:24
We also use the Lincoln 71M flux cored, but with straight Co2 shielding. Exactly what are you welding? We use about 27 volts on all of our procedures in the flat and horizontal positions. 30 volts seems to be alittle on the high side considering you are using a mix, it will cause more heat at the gun. Are your guns rated for 400 amps? If so I would look into the possibility of getting a new contact tip suppier. Another thing is flux cored wire does not recognize a spray transfer only solid metal wires deal with short circuiting globular or spray transfer.
By -
Date 07-01-2000 01:39
Are you sure you have the polarity set correctly?
By -
Date 07-03-2000 05:41
I ran into similar problems on two seporate occasions. One the ground was not sufficient and causing too much torch and tip heating. Anothe time the polarity on the power supply was reversed
Marc
We have had this problem before and we switched to a extended life contact tip this has cured our problem. I think the alloy used in making the tip is a little more resistant to heat effects.
Talk to you later.
