Projection Weld Studs

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have a question that I hope someone can answer. We have a job that has a 6mm stud with weld projections on the top side of the head (a surface stud) that is welded to .031 inch thick material. Normally you have a through hole with a stud that has projections under the head. My question is does anyone know of a spec for verifying the welds on a surface welded stud. What we were doing was a push out through the material until we pulled nuggets, which all three projections pulled good sized nuggets at a load of 1800lbs.The spec our customer gave us to use was GM6435M which specifically states that it is for a through hole welding operation. Gm says that there is a spec for a surface welded stud but they don't know what it is and that our checking method is invalid. We have also taken a coupon of the same thickness and punch a hole a little bigger than the diameter of the stud and performed the push-out going through the hole right to the head of the stud and have the exact same results as our previous check. Does anyone have experience or suggestions as to what the spec is or the correct checking method.
Reply:Also the material is 1008/1010 for both the stud and bracket
Reply:If the customer says, via paperwork on the contract, work-order, or whatever, that the applicable spec is GM6435M, then that is the applicable spec.  If they called out a spec for a through hole under-head welded stud as applicable to a surface welded stud, and they want you to meet 'spec', WTF are you supposed to do?If they want a different spec to apply to the job, then the paperwork has to call that out.  If they want a different spec to apply but they don't even know what that spec is, how the ^%#%# are you supposed to meet that phantom spec?  Mental telepathy?You sound like you want to do a good job, but the contract and paperwork is a bit confused as to what they want and what the work is supposed to do.  I'd suggest your folks talk to to their folks and straighten things out, otherwise the job, contract, payment, and so-forth could get messy.Maybe they want the welded stud to be tested for torque resistance, or pull-out resistance along the axis of the stud, or bending resistance, or shear resistance in the weld-plane, or some/any/all of the above?  But if they don't tell you what applicable spec they wany to meet, how are you supposed to know?
Reply:Moonrise,  That is exactly my problem. The customer does not know what the spec is. They say they want a torque but GM says that there is no spec for a torque on a weld stud with projections on the top of the head. And that a torque is not testing the welds and that the is no know comparasion between torque and pushout. We are not at fault because we were doing what the print asked for but they sure are trying to shift the blame.