Overhaul of moving blades of axial fans

- Nov 24, 2019-

Overhaul of moving blades of axial fans

(1) Remove the support casing, hydraulic cylinder, hub casing, support journal and adjustment disc, respectively.

(2) Check the wear between the slider and the guide ring, the gap is between 0.1 and 0.4 mm.

(3) Check that the fixing of the guide pin is firm and the degree of surface.

(4) Remove the connecting screws of the blade and the petiole and remove the blade. For the appearance and color inspection of the blade, if the blade has defects such as notches, cracks, severe wear and damage, it should be replaced. The screws that fasten the blades are for single use only.

(5) Loosen the lock washer and remove the lock cap. Remove the washers, adjustment arms, keys, collars, collars and bearings, respectively. Check that the bearing should be free of peeling, spotting, and discoloration.

(6) Pull the petiole out of the hub and inspect the petiole for flaw detection. The surface should be free of damage and not bent.

(7) Check the bushing in the petiole hole, it should be complete without scaling, no hair, and should be replaced if it does not meet the requirements. When removing and loading the bushing, use an exclusive copper rod and do not use tools such as a hammer.

(8) Check if the seal ring in the petiole hole is aging and fall off. If it is, replace it with a new one when reinstalling.

(9) After the blade is assembled, the 1mm turbulence gap should be maintained (adjusted by the lock cap), and the pieces should be the same.

(10) The surface of the blade should be smooth and free of defects, and the weight of each piece should be the same. The verticality of the end face of the petiole is not more than 0.02 mm. The keyway and thread should be intact.

(11) After the slider is cleaned, first soak it in a molybdenum disulfide oil at 100 °C for about 2 hours, and then install it after drying.

(12) The fastening screws at each point must be used with the required torque and with a torque wrench.