In this post, we can learn about 14 important rules for making good welds.

1. Metal expulsion, burned electrodes, bad welds, marked work, and damaged ignitron tubes or SCRs can occur if the squeeze time is too short.

2. Excessive weld time reduces electrode life, causes excessive indentation, and causes internal cracks, which can lead to weld failures.

3. The finished weld cannot be used to assess weld quality. Non-destructive testing requires the use of test strips of the same material and combination.

4. If all other factors are normal, a short weld time will result in a low weld strength.

5. Excessive hold time can cause surface expulsion, electrode sticking, internal cracks in the weld nugget, and even cracks in the parent metal. Follow the tables to save time.

6. Excessive weld pressure can cause metal expulsion, electrode damage (sticking), short electrode life, internal cracks in the weld nugget, and sometimes excessive indentation.

7. Excessive weld pressure can result in low or variable weld strength, excessive weld current requirements, electrode mushrooming, and excessive indentation.

8. Once all other settings have been verified, adjust weld current to meet weld quality standards.

9. A small electrode contact face results in a small spot, excessive electrode mushrooming, and excessive indentation. If the electrode contact area is too large, the weld will be too large (assuming the current is set appropriately) and will develop internal cracks.

10. Misaligned or mismatched electrodes will result in expulsion, displaced weld nuggets, and accelerated electrode wear.

11. Insufficient cooling results in mushroomed and short-life electrodes, surface cracks, and excessive indentation in some cases. It is critical that the water flow in through the water quill and out the other side. Every time an electrode is replaced, the water quill must be gently bottomed against the inside of the electrode cavity.

12. Dirty material - Dirt that adheres to the surface reduces electrode life and marks and burns the work surface.

13. Excessive electrode approach speed hastens electrode wear and damages equipment. It can damage the projection during projection welding, resulting in poor weld quality.

14. Do not weld over the same spot twice in an attempt to cover up a bad weld. To do so effectively, the work must cool before being subjected to a much higher current. If you can't get a weld in one hit, either your machine isn't set up correctly or you're not using a machine large enough to make the weld.


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