5 ms·

Must also take into account that many industrial processes are not easily restartable. Even if only shut down for 1 day or 1 week, it can take multiples of that

Must also take into account that many industrial processes are not easily restartable. Even if only shut down for 1 day or 1 week, it can take multiples of that length of time to ramp back up to 100% output rate. Complex factories do not switch on and off like a lightswitch.

onion2k 5y ago
My dad worked on some testing software for a float glass factory back in the 1980s. Float glass is a process where a factory makes a continuous sheet of glass that floats on a river of molten tin, about 3 meters wide, 24 hours a day. It never stops. If it does then the glass cools down and solidifies inside the machinery, and the factory needs to be practically scrapped and rebuilt. I imagine that's the worst case scenario, but many large scale manufacturing businesses are likely to have similar processes that can't be stopped easily, and that cost a fortune to restart.
- Dylan16807 5y ago
  > It never stops. If it does then the glass cools down and solidifies inside the machinery That's why you can't just flip a switch to turn it off. But what if you stop feeding glass in and wait half a day first?
  - depaya 5y ago
    Couple of things to consider: Many of the processes might require the product is pushed and/or pulled through the machinery. If there is no material behind to push it could cause problems within the machines. Once the continuous process is broken it needs to be restarted somehow. Depending on the type of production this could be days or weeks of work just to rethread all the material through the machines and getting it going.
    - Dylan16807 5y ago
      I'd certainly rather rethread than rebuild.
      - depaya 5y ago
        Might not be an option. If the material hardens in the machine it might need to be completely disassembled and rebuilt with many of the parts requiring replacement (since it wouldn't have been designed with disassembly in mind).
        Dylan16807 5y ago
        > If the material hardens in the machine Now you've gone in a circle. That's what the original comment was talking about. This subthread is hinged on the idea of that specific problem not happening.
  - onion2k 5y ago
    I don't know. I imagine it takes a lot longer than that to cool down though, ans perhaps you can't run the machinery without glass in it to take the heat away?

onion2k 5y ago

My dad worked on some testing software for a float glass factory back in the 1980s. Float glass is a process where a factory makes a continuous sheet of glass that floats on a river of molten tin, about 3 meters wide, 24 hours a day. It never stops. If it does then the glass cools down and solidifies inside the machinery, and the factory needs to be practically scrapped and rebuilt. I imagine that's the worst case scenario, but many large scale manufacturing businesses are likely to have similar processes that can't be stopped easily, and that cost a fortune to restart.

Dylan16807 5y ago
> It never stops. If it does then the glass cools down and solidifies inside the machinery That's why you can't just flip a switch to turn it off. But what if you stop feeding glass in and wait half a day first?
- depaya 5y ago
  Couple of things to consider: Many of the processes might require the product is pushed and/or pulled through the machinery. If there is no material behind to push it could cause problems within the machines. Once the continuous process is broken it needs to be restarted somehow. Depending on the type of production this could be days or weeks of work just to rethread all the material through the machines and getting it going.
  - Dylan16807 5y ago
    I'd certainly rather rethread than rebuild.
    - depaya 5y ago
      Might not be an option. If the material hardens in the machine it might need to be completely disassembled and rebuilt with many of the parts requiring replacement (since it wouldn't have been designed with disassembly in mind).
      - Dylan16807 5y ago
        > If the material hardens in the machine Now you've gone in a circle. That's what the original comment was talking about. This subthread is hinged on the idea of that specific problem not happening.
- onion2k 5y ago
  I don't know. I imagine it takes a lot longer than that to cool down though, ans perhaps you can't run the machinery without glass in it to take the heat away?