Vulcanizing autoclaves

At ATTSUKLAUS we manufacture autoclaves for vulcanization by means of the following techniques:

Direct steam technique

The tires or rubber parts are loaded on the platform and introduced into the autoclave. The door is hermetically closed, pressurized steam is introduced and the steam temperature is maintained for the programmed period of time. In addition, compressed air can be added to the process to increase the internal pressure above the pressure marked by the temperature of the steam.

Indirect steam with third pressure technique

  1. A rubber cover called ‘envelope’ is placed which covers the tire completely, the envelope is composed by a valve through which releases the third pressure.
  2. The tires are introduced in the autoclave and the hoses are connected to them for pressurization. Subsequently, the autoclave is hermetically closed.
  3. The steam from the boiler is not introduced directly, it is introduced through a heat exchanger where the steam heats the air that is introduced into the autoclave. As the temperature increases, up to 125 °C, the air chambers inside the tires are blowed up while the autoclave starts the pressurization. Thus, it exists a gap of pressure of of 30psi (2.1 bar) between the tires chambers and the autoclave. The pressurization continues until the pressure of the autoclave is 80psi (5.5 bar) and the pressure in the tires 115 psi (8 bar).
  4. Subsequently, The cover of the tires is pressurized up to 60 psi (4.2 bar). This pressure is known as the third pressure and allows a better bond and a better finish. The duration of this process is 150 minutes.
  5.  At the end, the pressures are discharged in the following order: third pressure, tire pressure and finally chamber pressure.