There are two main reasons for the promotion of zigzag-shaped mid-disc technology in the country. Two of them are most representative: 1) It is recognized that it has wear-resistance, but it is considered to have no effect on the improvement of aerodynamic performance and efficiency. 2) It is considered that the circular middle plate is cut into a toothed disc-shaped notch, and its strength is inevitably lowered. The safety of the impeller must be poor. The outer edges of the middle plate are smaller in Rr and RH, and certain materials are removed, from the circumferential direction of the middle plate. It is observed that the area where the stress is greatly affected by the centrifugal force of the blade is retained, and the part with less stress is also reduced, and the average mass radius of the middle plate (and the impeller) is reduced, similar to the structural principle of the steel pipe, the I-beam and the twist drill. It is also similar to the stress condition of the arch (hanging) bridge. The supporting force is transmitted from both sides, and the middle of the bridge is not necessarily too thick. The middle plate looks weak after removing the material, but the stress is reasonably distributed. The best use is scientific and safe. The general double-suction induced draft fan impeller can be slotted. The shape, size, depth and bottom radius of the groove can be Calculated and empirically determined, its specific structure and manufacturing process can also be improved and innovative.
In summary, the author believes that the technology does not need to replace the new impeller without the need to add heavy anti-wear panels, no need to spray expensive wear-resistant materials, benefitless, simple and convenient, economical and effective, from the power plant fan wear-resistant From the point of view of safety, reliability, energy saving and high efficiency, from the goal of re-development and transformation of the domestic wind turbine industry, it is necessary to promote the promotion of the double-suction induced draft fan serrated medium-disc impeller.