Why is the cast aluminum rotor broken?
(1) The misalignment or clogging of the core slot reduces the cross section of the slot to cause blockage; the leakage of the individual punch slots and the inclusions brought in during the preheating can block the slot, so that the aluminum water is blocked during the pouring. .
(2) The rotor cage is pulled off. When the rotor core is over-tightened and the core is pulled out, the cage may be pulled off when the core is raised outwards. If the aluminum water has not completely solidified during demolding, the cage will also break due to premature knocking of the mold. When the aluminum is vibrated, the cage is often broken due to the long vibration time.
(3) Stopping during the pouring. Since aluminum is extremely oxidizable, the aluminum water poured after the pause cannot be melted with the aluminum water in front, causing the cage to break.
(4) The air holes in the slot break the cage.
(5) The temperature of the core is too low to affect the fluidity of the aluminum water, which has a great influence on the gravity cast aluminum.
Measures to prevent broken bars
(1) Strengthen the inspection before pouring to eliminate the misalignment and blockage of the slots.
(2) When the rotor core is laminated, the stacking pressure is controlled so as to be no more than 4 MN/m2. After casting the aluminum, the aluminum water is completely solidified and then released.
(3) When pouring once, it must not be stopped in the middle.
(4) Properly increase the core preheating temperature.
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