Fusion weld symbol? (Autogenous Weld)

By zm1001 Date 04-23-2015 16:28

We weld various thickness of stainless steel sheet metal, from 16 gauge - 3/8" plate. Some of our welds are fusion welds / autogenous welds, no material is added. Is there an AWS standard symbol for this type of weld? If not, would an acceptable practice be to use an existing weld symbol that looks like the shape, but add a note to the tail "Autogenous" ? For example, (2) pieces of plate making a T shape, welded along both sides, the weld would look like concave fillet weld but no material is added.

By 803056

Date 04-24-2015 13:57 Edited 04-24-2015 15:52

The parameters for welding, i.e., process, filler metal, shielding gas, voltage, amperage, etc. are included in the appropriate WPS. In this case; autogenous welding, the information for filler metal, i.e., specification, classification, diameter, etc. would be "NA".

Some companies include a reference to the applicable WPS, process, filler metal, size and type of backing, etc., in the tail of the welding symbol. It isn't my preference to list the WPS or filler metal in the tail of the welding symbol. The means and methods (in my opinion) should be addressed by the traveler that delineates the sequence of operations.

Think of it this way, the print should include a graphical representation of the part that will be constructed. I do not include anything on the drawing that I would not want a subcontractor to have access to. Anything to do with the ways and means of manufacturing the part is left to the contractor responsible for making the part. The contractor should have the option of using the welding process that is appropriate for their manufacturing operation. The means and methods should be addressed in a traveler. The traveler would address the manufacturing sequence and the specific equipment utilized. The manufacturer would then have the option to use a laser cutting operation rather than a shearing and punching operation. The manufacturer would have the option to weld the component with SMAW, GTAW, or FCAW as long as the final product meets the criteria of the customer.

The WPS is the vehicle used to tell the welder how the component is to be welded. Usually, the customer has an opportunity to review the WPS before it is used in production. That is the customer's opportunity to make comments to their preference of welding process, filler metal, etc. The WPS tells the welder exactly what welding process is to be used, the need for filler metal (if used or required), the diameter, etc.

Just my opinion.

Al

By Metarinka (****)

Date 05-20-2015 22:27

In general you have a note in the tail or drawing that welds are autogenous. Also depending on the geometry you can use the melt thru symbol to referred to the fact that you are melting down two edges to form a piece with no filler.

I personally always used a note in the tail, easiest method in my opinion.

By Mickymost Date 06-27-2015 21:50

Hi
Al is correct. The WPS defines if filler is used or not. This is an essential variable so if defined on the WPS it must be used.
The weld symbol will not state if it is required as is it was a single vee groove weld you would have to use it to fill the groove up. If it was a square butt in thin (e.g 1/16) material then you might not need to use it. Basically its all about the type of join, material or proces that defines if filler is used or not.