For the experts, it may be very easy to differentiate between a good weld and a bad one. However, for the non expert ones, how is it done? This may be easier said than done, however after few times and practices it will be assessed very easily.
What are the characteristics of a good weld?
Straight and uniform with no slag
There will be uniformity and one will not see any inconsistencies.
There will be no cracking or holes
If you see any sort of breakage you should know it has gone bad.
It should not be very thin
Too much thin structure can indicate that it is in fact not the best option.
No dips in the bead
This is another important indicator.
What are the steps necessary to check a good weld?
The below steps are necessary to check a good weld.
Do a x-ray test
This will not take time neither will it be very costly.
Do a magnaflux test
This is also time and money friendly.
Do a dye penetrant test or ultrasonic test
Consider this time and money friendly as well.
Look for voids, lack of fusion, etc.
This can be done with the ultrasonic testing, however keep in mind you are doing these checks.
Which techniques exist to test a good or bad weld?
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Does the weld that looks bad is bad in actuality?
No, if it looks bad it is not necessary that it will be bad and that is why the above tests have been specified. Through these tests it is considered whether they are actually bad or not. However, a good weld has to be strong and durable for sure. Sufficient penetration will be another sign of a good weld.
What are the different type of welding?
These are the different type of welding and these are the most popular.
- TIG Welding – Gas Tungsten Arc Welding (GTAW)
- MIG Welding – Gas Metal Arc Welding (GMAW)
- Flux Welding – Cored Arc Welding (FCAW)
- Stick Welding – Shielded Metal Arc Welding (SMAW)
- Atomic Hydrogen Welding (AHW)
- Energy Beam Welding (EBW)
- Plasma Arc Welding
- Gas Tungsten-Arc Welding
It is for you to make the right choice as a one time investment should be done in the right and correct choice. Do not waste time and money over a bad weld that will in return do you no favour, and in fact, will end up worsening your situation. There will be welding machines that will be classified as: Mig (metal inert gas) welding machines, Thyristor Control Mig welding machines, Tig welding machines, Spot welding machines, Shielded metal arc welding machines. Find your best match and stick by it! Good luck.