It is an economical and simple demolding method commonly used in spinning. The specific demolding structure principle is shown in the figure below. The CNC spinning machine tool connects an air pipe to the spindle mold. When the air pipe is pressurized, the air in the air hole is blown. The pressure is greater than the pressure outside the mold. When the product spinning is completed, the top of the tail leaves the spindle mold. The air pressure difference between the inside and the outside will make the spinning product separate from the mold smoothly, but the air pressure should be adjusted within a reasonable range. The air pressure is too small, and the product unsmooth demolding and excessive air pressure may cause the product to fly out of the mold and be injured.