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Hi Guys,
I've been working as a Mechanical Engineer in the mining industry in WA for a few years now. A lot of our work tends to involve welding – predominately structural steel and pipework (generally carrying water). I am competent in creating fabrication drawings (including weld symbols) and calculating weld strength. Structural steel I am involved with is mild steel (grade 250-350) and pipework is mild steel or stainless steel welded with either MIG or stick. In the past I have just specified all welds to the relevant Australian Standard for instance AS1554.1SP for structural work.
My question is, how do I create weld procedures for these relatively simple welding processes? Do they have to need to comply with any standard? How do I know; which electrodes to specify, welder settings, pre/post weld heat treatment, weld speed etc. Is there a course I can do or textbook which covers the topic? I want to be confident in telling the welders what they need to do.
Regards,
ConorHi Conor
If you look through the 1554 standards (they are a set of 7) they will give you set of pre-qualified parameters and guidelines to follow.
Someone with a Certificate 10 or a welding inspector for example can do the procedures and show you what is required. The WTIA has a set of guidelines as well that one can follow especially where pre heat and post weld heat treatment is concerned.
Yes the weld procedures are required to comply with the relevent standard. If your stuck Im sure there are a few of us here that can help out
Is there no one available in your company able to carry this out?
Cheers
Hi Conor
The question how do I write a WPS is like a welder asking how do I design a steel structure, there is a great deal of knowledge that goes into it, it is great that you are interested
these are broad statements so please treat them that way
1. If you have qualified experienced welders, do not tell them what to do when trying to qualify a WPS, with Gr250, 300, 350 just record what they do and apply the essential variables out of the relevant standard, if you try and get them to conform to what you want, they will do it for the test and then go back to doing what they were doing anyway, you are better of proving what they are doing works, unless you have a good reason/justification to get them to change (if the material/service conditions warrants tight controls this is different ie DSS or SDSS)
2.electrodes to specify from the engineers point of view should just list Min TS or YS if we are talking about Gr250,300, 350 (maybe you could state maximum hydrogen level for critical applications or thick sections but not normally)
3. preheat can be calculated using AS1554.1, but keep in mind this does not consider highly restrained jointsMy tip to you would be pick a good friendly welder or two and talk to them and exchange knowledge, most welders like to know a bit about engineering/design ‘stuff’ just like you would like to know more about welding
Good luck
R
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