Blast oven

The utility model discloses a blast drying oven which comprises an oven body and an oven door arranged on the side face of the oven body and used for opening and closing the oven body, a strip-shaped fan is installed at the position, close to the oven door, in the oven body, and the strip-shaped fan comprises an air outlet. The direction of the air outlet is parallel to the direction of the box door in a closed state, and the length of the air outlet is matched with the length of the strip-shaped fan mounting surface, so that an air curtain for covering the box body is formed when the box door is opened; an exhaust outlet is formed in the side wall of the box body, a vacuum pump communicated with the interior of the box body through the exhaust outlet is arranged outside the box body, and a flow guide plate is arranged in the box body and located between the vacuum pump and an air curtain formed by the strip-shaped fan. The strip-shaped fan is arranged to form an air curtain at the box door, airflow exchange