ASME Sect IX Welder Performance Test: Issue w/Discarded Section

[tc7]

ASME Section IX (2007) welder qualification requirements QW-304 stipulate that visual and bend tests are the principle method of testing for groove welds. Referenced table QW-452 for ¾” thick material and above primarily want 2 side bends and visual examination.

There seems to be no indication on how long the weld plates need to be. So our practice is to have 6-inch long plates made up for each welder test.

By the cutting diagram shown in QW-463.2(a) and (b), we are permitted to discard approx 1-inch of either edge of our 6-inch plate and conduct testing on the center region only. Also QW-302.4 allows the “discard” areas to be free from visual examination.

Question #1: why is discarding the edges permitted? These are likely to be the most vulnerable areas for porosity and slag entrapment to occur, why are they excluded from examination? Production welds don’t have the option of exempting the first and last inch of welds from inspection.


Continuing…QW-304 allows alternative welder qualification by radiographic examination and for plate tests, a plate length of 6-inches minimum is appropriate.
I can find no Code language that allows the edges of a radiograph inspected test plate to exclude the edges from inspection. So if porosity shows in the 1-inch wide edges then I am requiring retests which has gotten certain seniors quite upset with their claim that “all” Code shops discard one inch on either side from the x-ray.


Question #2: aside from what some Code shops may do about exempting the 1-inch wide edges from inspection, what does the Code require/allow for x-ray welder plate qualification?
There seems to be an inconsistency with how the edge margins are treaetd between the alternative x-ray and the visual w/side bends.

Help,
Thanks

 

[vesselfab]

when we radiograph for welder qualification, it is in production. NO EDGES.

We qualify new welders on bend tests.

If for some reason a welder runs out of time on welders performance log, we requalify in production.

 

[weldtek]

# 1. They're excluded from examination because stops and starts are prone to defects. In production we use runoff tabs to avoid that condition.

# 2. Per Code, a minimum 6" long film is req'd. Use 8" long test plates or run off tabs.

 

[gtaw]

Welder performance qualification is simply a demonstration the welder can deposit a sound weld. Depending on the welding standard invoked, it can be as short as three continuous inches.

Welding standards and codes list the minimum requirements that have to be met. The manufacturer or contractor must meet the minimum requirements, but there is nothing that says they can't go beyond the minimum requirements and insist upon a higher standard of "quality".

In my own practice I use 8 inch plates to ensure the welder will have to stop and restart the weld when using SMAW. The acceptance criteria I apply to the visual examination is the visual criteria of the applicable construction code (which is listed on the welder qualification record). This ensure the welder can desposit sound welds capable of meeting the applicable construction code. There is nothing that disrupts production more than a welder that meets Section IX, but can't meet the visual criteria of the construction code.



Best regards - Al