In-furnace air pressure control device and method of oriented silicon steel high-temperature bell type furnace

The invention relates to an oriented silicon steel high-temperature annealing device, and in particular, designs an in-furnace air pressure control device and a method of an oriented silicon steel high-temperature bell type furnace. The in-furnace air pressure control device has an intake pipe positioned in the center of a base of the bell type furnace, and an exhaust pipe positioned on the outer side of the base; a manual spherical valve is arranged on the exhaust pipe; a periodic-adjusted bypass device is arranged beside the manual spherical valve on the exhaust pipe; the two ends of the bypass device are communicated with the exhaust pipe; and the manual spherical valve is positioned between two connecting places of the bypass device and the exhaust pipe. The in-furnace air pressure control device is additionally provided with the periodic-adjusted bypass device for changing the air pressure in the bell type furnace from fixation to sine periodic fluctuation, generates a pressure difference between the air