AWS

I am not sure there is a set calculation for this. A very small amount of wind can blow the shielding gas from around the molten weld puddle and let the air contaminate it. I found that SMAW is better for windy area than say any type weld that utilizes a inert gas shielding such as GTAW. You need to know how to recognize when it becomes a problem and build wind breaks around to block it. I have welded in some pretty high winds back in my offshore pipe welding days and we just had to take the time to build temporary wind, rain etc. blocks before we started. When you are making X-ray quality welds you can't take a chance on wind, rain, oil, dirt or any other contamination that could cause bad welds. It has been my experience that it is the welders responsibility to spot these problems and take the appropriate measures to insure a quality weld. Most companies I have welded for only allow 2 or 3 bad welds and then welder is terminated so it is up to the man making the welds. Having said this any supervisor or quality control person should back the welders decision and supply him the materials to make the quality of weld they require.

pipewelder

Dear Pipe-welder,

I agree with you all. Contaminated weld can be determined by doing some test. But it all after you welded days progress and when found unsatisfactory weld, all days work is recommended by Inspector to Cut Out. The only solution to this loss is to stop welding or provide satisfactory shielding. If some one was not prepared for such occasion, small wind blow to some Inspector is satisfactory and to some one not. I was looking for solution to the disagreement between the Contractor and the Inspector. I know the best is to carry wind shield or tent all along the pipeline project. But this also hinders the day's progress if not a lot but it does. I have an idea to through it on Cr 4 thread for some mathematician to draw equation. Now the given fact is: Cross Country pipeline is mostly welded with SMAW process using cellulose coated electrodes. When electrode is struck to the work, the flux burns and generates Co2. At the same the droplets detached from electrodes falls into the puddle and get deposited. The droplets and the puddle is protected with gas plasma which is pulled towards the work due to electromagnetic force. If the method is found to determine the strength of the electromagnetic force, one can limit the velocity of wind-low that may be strong enough to break the electromagnetic force, which is injurious. Velocity of wind-blow less than the determined, should be the maximum limits of wind blow to weld openly. Is mathematician listening the chalange?

Abdul,

Could you refer us your reasons for this query? Pipewelder is correct and nobody could specify which limit, it is only a practical decision and you may carry out statistical data of discontinuities vs weather if you are tried to include a value in any procedure.

Disagreement on opinions. Contractor and Inspector don't agree on said velocity.

The point I was trying to make was that any amount of wind could possibly blow the shielding gas from a molten puddle if it hit it from the right direction. So it is not as much as how strong of wind but from what direction. I am sure one could do an experiment and determine exactly how much wind it would take to overcome a particular shielding gas weather it be flux generated or an inert gas. When you consider doing it for all angles and circumstances the possibilities are infinite. In the field conditions will always be different on every weld. When a welder that routinely makes x-ray quality welds makes a weld they know when the puddle is not being shielded and should immediately stop welding when this occurs. This is considered part of the skill of welding as much as knowing what type manipulation will be used to root,fill or cap a particular weld, what heat to set the machine or even knowing when a particluar weld is acceptable. In todays construction industry I cannot see wind stopping weld production unless it strong enough to be a safety issue. It will many times slow down production when you consider manpower to build the proper wind blocks to provide a way to overcome it's damaging effects.

Pipewelder

The SMAW electrode you speak of I am assuming is a XX10 or would be here in the USA. This electrode was probably chosen for its fast freeze s and deep penetration characteristics which allow the welder to weld in a up or down hill manner. This characteristic also helps in a wind area because the puddle tends to cool quicker than other type electrodes. I am also assuming you are getting porosity in the weld as your defect? At any rate why does the welder not tell you he is having problems with the wind when it happens rather than wait till the inspector finds it a few days later? I am sure you all may do things different in your country but anywhere I have ever welded if we get a problem we fix it before we go to the next weld.

pipewelder