By 803056
Date 12-20-2011 04:37
Edited 12-20-2011 05:01
I have no problem with controlling the width of a weld bead as long as it not based on unfounded personal opinion or "because it is required by code".
There are reasons to control bead width with certain materials or for certain service applications, but anytime restrictions are place on welding technique there are costs associated with those restrictions.
My experience has been that when restrictions are put in place, it is usually not based on metallurgical considerations, but on personal opinion based on "how we did it on my last job" mentality. The mentality; "I can make as wide a weave as I want, because that's the way I've always dun it" is just as bad as "no weave more than 3X the diameter of the rod" when neither is based on sound metallurgical principles.
Restrictions imposed on the welder that ensure consistent results from one welder to the next, that is to say ensures the mechanical properties are met consistently are reasonable and justifiable. Unnecessary restrictions imposed because "that's the way I want it" are often wasteful and detrimental to producing welds with the required properties.
Raptor; I don't want to cast dispersions your way, but that is one of the points I was trying to make. The inspector's personal opinion should be held in reserve. Acceptance criteria included in most welding standards is not based on the opinion of one person, but a group of people that have extensive experience that usually have test data to substantiate their position. The welding standard sets the ground rules, the inspector simple determines if the rules are met or they are not met. The inspector, working in isolation, is not the individual that formulates the rules. Few codes include terminology such as "first class workmanship", "in a professional manner", or "professional appearance". Those criteria are subjective rather than objective. They provide no means of applying metrics to the welds being evaluated. Instead, most welding standards are prescriptive define the empirical acceptance criteria, i.e., undercut is limited to 1/16 inch depth, overlap is prohibited, face reinforcement is limited to 3/32 inch, etc., so any accept/reject decision is objective rather than subjective. Any two or three inspectors should be able to examine the same weld and come to the same conclusion based on objective criteria. When subjective criteria are the basis of inspection, no two inspectors will judge the weld the same.
Best regards - Al