For what it’s worth, that’s how a lot of critical welds are verified. X-raying welds is fairly standard practice in the field if the strength of the weld is important enough. And it’s not as much about trust as how much it is fairly easy to make a mistake while welding and not know it. A good welder paying close attention can tell whether a weld is good with fairly high accuracy. But that’s not always enough certainty and when skilled honest people make mistakes here, they won’t nevessarily know it. So, you X-ray.

They x-ray (or even gamma-ray) every cm of welds on the natural gas pipelines that crisscross the country.

These pipelines can be over a meter in diameter and perhaps (from my recollection) a couple of cm thickness. Consequently, the x-ray machines are not machines one wants to be near when operating, they are quite powerful.

I learned this during a summer job in college at the research labs for a large gas pipeline company in the early 70's. At the time a "pig" was used to provide the x-rays for checking the welds of under-sea gas pipelines while they were being constructed. This pig was a remotely controlled wheeled device that moved from weld to weld and x-ray film would be put on the outside of the steel pipe for exposure. The pipe segments were welded together on a barge that floated in perhaps the Gulf of Mexico. Because the welding took several separate passes around the pipe it was done in a continuous operation with the pig x-ray as the final stage before the pipe slid off the back of the barge into the sea.

Normally, the pig motored toward the open, working end, of the pipe as new sections where being assembled on the barge. Once, the pig malfunctioned and took off in the wrong direction; it rolled down to the sea-floor. A guy from the pig company had to be flown to the gulf. He was rolled down the pipe lying on something like a skateboard (attached to a rope) to retrieve the pig!!!

Issues with the new class of nuclear power station designed by EDF ("EPR") currently in the works in the UK, Finland, China and France have been spotted via xray as well.

The french plant (in Flamanville, Normandy) has a number of faulty parts, including the cover of the pressure chamber.

Latest article in english I could find is this http://www.world-nuclear-news.org/RS-Flamanville-EPR-weld-ch... but since, several other defects have been found.

EDF is currently lobbying for an OK from the nuclear safety regulator despite the faulty welds. Earlier this week I read that the deal would be something like a reduced lifespan for the cover with yearly inspections. Some even said that the alternative is basically to torn apart the power plant, remove all the machinery, redo it, re-deliver it and pray for quality welds this time.

The chinese ones are about 1 year behind schedule. The english one (Hinkley Point) is 15 months behind schedules, also because of quality issues. The finnish one (Olkiluoto) is almost ten years behind schedule. The french one (Flamanville) is 8 years behind schedule.

In most cases, EDF is liable for damages because of the large delays.

This fault looks like it was not on a weld, but elsewhere on the surface. Though probably close enough to some kind of join, if the worker slipped with a drill.

10% of the pieces in a Ferrari are inspected using x-rays. This ensures the motor has no defects, the bad pieces are melted again[0]. X-raying does not cost a lot nowadays and definitely helps the quality.

[0]: https://www.evo.co.uk/ferrari/10140/making-of-a-ferrari

Isn’t that part of the SUBSAFE protocol?