The invention relates to a longitudinal-circulation
autoclave provided with an external thermal-cold
cycling device. The longitudinal-circulation
autoclave comprises a main tank body, air suction connection pipelines, air blowing connection pipelines and the thermal-cold
cycling device, wherein the main tank body is connected with
airflow distributors through the air suction connection pipelines and the air blowing connection pipelines respectively; the thermal-cold
cycling device is located outside the main tank body. According to the
autoclave with the structure, the complicated heating, cooling and circulating device is moved out of the main tank body, and
loading rate is remarkably increased; the circulation path is shortened by means of a new longitudinal-circulation mode, and under cooperation with the
airflow distributors, the temperature distribution in the tank is uniform, vertical
temperature difference is reduced, and front and back
temperature difference is almost zero; with adoption of an
electromagnetic heating mode with higher efficiency, not only is energy saved, but also efficiency is remarkably improved; the external thermal-cold cycling device can be wholly replaced and dismounted for maintenance due to presence of spare parts, and the condition of production
delay caused by equipment failure maintenance is avoided.