High confidence is based on the word Rivettura - rivetting. Here we are in a factory and this is about the design of the product, things like how many rivets to bang in an where precisely to put them.
I was writing this in the discussion box until I noticed this clue to the context:

What does the company do? I have just done a quality manual for consulting engineers (civil engineering, tunnelling). I know that when they say commessa, they mean project, when they say progetto, progettazione they mean design. I also translate for urbanisti, and when they say progetto sometimes they mean project, sometimes plan and sometimes design, but I know that when they same progettazione they usually mean design. So please Therese, what do these people do? Are they civil engineers, town planners, architects or what, something completely different?

The are manufacturers of metal goods.

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Note added at 21 hrs (2014-02-16 09:30:05 GMT)
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Then design would be just right.

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Note added at 21 hrs (2014-02-16 09:40:00 GMT)
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Well, you have to see. However, a company that designs aircraft must have a design department. Companies don't usually have a specific "planning department". All departments will do planning and the design department would presumably need to plan its training. In the manual I have just done, they used the word pianificazione for planning.