Iwona,
It is commending your endeavour to learn the design of these industrial autoclaves.
They are essentially pressure vessels operating at somehow elevated temperatures, for which any recognised pressure vessel code will give you guidance for design. The fans and the source of heat is a complex thing, you buy them fully certified, you don't need to design them.
The hardest part is the quick opening closure which is not really designed per pressure vessel code, but these are proprietary designs (conforming also to the pressure veesl code), strictly protected by copyright laws. To design one from scratch would require many years of experience in that field and the new design would have to be certified as per the regulations. The certification requires extensive and expensive tests. Nobody with sane mind would buy a new design without certification. You cannot install one closure without certification.
So, don't despair, you still can learn the design of these pressure vessels (study the ASME or EN or other codes), then find a way to work with a closure fabricator and get involved with the design team. I don't think you can get in a hurry a set of calculations for an existing closure (confidentiality reasons), but if you get your hands on an old design, study it to understand the principles.
Many years of hard work, but eventually you'll be a successful designer of industrial autoclaves.
Good luck,
gr2vessels
