10.024  Is an Overhead Puddle Weld Possible?

I have specified an overhead puddle weld on a project and the contactor is claiming that they cannot perform this weld. I'm attempting to determine if the contractor is correct. Do you have any thoughts on this?

-- Structural Engineer from Oakland, CA.

1/17/07 - Response prepared by Greg Ruf, Managing Engineer for Krazan & Associates' San Francisco Bay Area Operations

Puddle welds are typically used to join sheet metal to underlying structural steel elements. These welds are generally completed by using high heat settings to allow for burning through of the sheet metal. With the higher heat required for this welding technique, a larger weld puddle is formed than would typically be created with the use of a lower heat (amperage) setting.

The connection strength of the puddle metal is a function of the perimeter area of the weld. With the larger puddle area of a puddle weld versus that of a linear weld or plug weld, and the higher heat of the molten metal, the application of a puddle weld is governed by gravity. The forces of gravity do not allow for the creation of a larger weld puddle as is common for a puddle weld in any position other than the flat position.

1/17/07 - Response prepared by Dave Palfini, Principal, ASNT Level III, AWS SCWI, Testing Engineers, Inc., San Leandro

Arc spot (puddle) welds and arc seam welds are only done in the flat position. See AWS D1.3-98, Table 1.2. It is almost impossible to do them in any other position.

1/17/07 - Response prepared by Doug Williams, Consulting Metallurgical and Welding Engineer

The simple answer is that if the contractor won't do it, it's not going to get done - regardless of theory.

See D1.3-98 Table 4.1 for standard joints. #4.4, Arc spot weld-sheet to supporting structural member is only shown for F, i.e., flat welding only. #4.5B is only shown for the horizontal position.

The relevant all-position weld might be #4.5, the arc plug weld.