I have worked on factory floors before but honestly I don't see how it's relevant. Toyota and similarly competent manufacturers are are perfectly capable of using centralized databases to track the motion of parts around extremely convoluted manufacturing plants. Blockchain primarily solves the double-spend problem of a distributed spreadsheet. So some supplier can't claim to have sent the same parts to two factories on some spreadsheet. That's solving a non-problem. I expect blockchain to have a massive impact on industries primarily concerned with abstract ledgers (finance), but I have serious doubts about the utility of the technology when applied to problems involving meatspace. I would be happy to be proven wrong.