For advanced composite parts that require an elevated temperature cure, an oven or an autoclave (a cylindrical pressure vessel with heating and cooling capabilities) may be prescribed. The parts are generally laid-up, vacuum bagged, and placed in the oven or autoclave for processing.
Both ovens and autoclaves are fitted with vacuum plumbing and thermocouple connections. Autoclaves typically have advanced vacuum/venting capabilities to allow the vacuum lines to be vented to the atmosphere or regulated during the cure process. In addition, there may be special tracks and racks for loading and unloading large parts or groups of smaller parts.
Temperature controllers range from single-setpoint manual devices to full-blown computer-aided control systems that may be necessary to control hundreds of sensors in the oven or autoclave, and on multiple tools and parts during the curing process. Both ovens and autoclaves have heaters and fans that provide convection heating in a manner that uniformly distributes the heat throughout the vessel.
Autoclaves also have water cooling capabilities where cool water is distributed via plumbing within the vessel for aid in cooling the part during the cool-down portion of the cure cycle.
Ovens are normally rectangular and usually have simple hinge/latch mechanisms because they have no internal pressurization capabilities. Autoclaves are cylindrical in shape and have dome-shaped doors that have a rotating lock-ring or doorlocking design to provide clamping, sealing, and safety functions during pressurization cycles.