The root of the weld is the most important part. Because of this fact, most tests require inspection of the root before moving on to the next part. If there are any defects, it may require a repair. Repairs are only allowed if the welding inspector says they can be done. At this point, you are at the mercy of the person overseeing the test.

Joint preparation typically requires the welder to prepare the materials that will be welded. In most cases there will be "weld test coupons" already prepared for you. Once you receive the coupons, they will need the mill scale removed from the weld area and bevel angles checked. After that they are tack welded together and rechecked again. Most pipe welding procedures require a gap opening ranging from 1/16 to 1/8 of an inch. Then the test is put into position and cannot be moved from that position at any time during the test without the permission of the welding inspector.

When it comes to the fill and cap, it is pretty straight forward. In most cases(aluminum pipe) nobody is going to see your fill and the cap until the test is completed. That is in most cases but not always. There are times the inspector will check and if you are struggling, you could fail on-the-spot. Some general rules for the cap are: no undercut greater than 1/32 of an inch, weld reinforcement should not exceed 1/8 of an inch, and the weld must be flush or higher than the test plates.

Key words:   aluminum pipe , pipe 

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