dewayne, my experience with prequalified WPS is that most clients don't allow it. It would be wise for you to get permission first before you proceed to use it. You still have to write the WPS for the joint details that you will use and you still need to qualify or qualified welders. The problem with prequalified WPS centers around the problem of control. This is because each WPS that you write will be limited to a particular joint detail. Depending on the complexity of your job, you could end up with a great number of WPSes. Then you have to amend your shop drawings with notes at the end of the weld symbol indicating the particular WPS to be used for each weld joint. This may cause some confusion to welders and inspectors.

Dewayne,
When testing welders they need to weld using a written WPS.  The code does not specify what type of WPS, meaning it could be a qualified WPS (per Clause 4.0 of D1.1) or a prequalified WPS (per Clause 3.0) or it could simply be a WPS that is written solely for the purpose of testing welders.  This written WPS needs to cover all of the essential variables stated in 4.7 and 4.22 of the code.

To get your welders certified for fillet welding in the vertical welding position, go to 4.25.  There it tells you that if your welders have already qualified for CJP groove welds they are automatically qualified for fillets.  If not, then it tells you to go to Table 4.11.  About halfway down the first page of Table 4.11 you'll see "Production Fillet Welds" and under this you'll see three different options for obtaining fillet weld qualification (1, 2, and 3) - each of those three takes you to a different Figure.  In my experience most code users find Option 1 to be the most convenient.  According to Table 4.11 you need to use 1/2" plate to do a fillet weld break test and a macroetch, and this will qualify your welder for unlimited thicknesses.  If you go back to Table 4.10, you'll see that to be qualified to weld in vertical the qualification test needs to be done in 3F position (your welder will actually be qualified for flat, horizontal and vertical).

If you go to the Figure 4.37 referenced for the Option 1 fillet weld test in Table 4.11 you'll see the test plate configuration.  A couple of things you should keep in mind.
- The welder must stop and then restart the arc near the centerline of the weld length.
- The required fillet weld size is 5/16" minimum.  This is very close to the limit of what you can do in one pass for some processes while keeping the arc at the front of the puddle.  It is generally better to run two smaller passes.

Once the test plate is welded, refer to 4.19.  There it will send you to 4.8.1 for the VT requirements, 4.30.2 for the macroetch, and 4.30.4 for the fillet weld break test.  Clearly you will want to cut off your macroetch specimen (location as shown in Figure 4.37) before you do the break test.

Hope this helps,
Mankenberg