Common Two Faults of Ball Mill Gear and Their Solutions

The gear of the ball mill is one of its most important structural components, including a large gear and a small gear. If there is a malfunction in the gear, it will greatly affect the overall operation of the ball mill. Here, we introduce the two common faults of the ball mill girth gear and provide detailed solutions for each. We hope to help customers solve practical problems in the application process of wet ball mills.

Severe vibration of the small gear in industrial ball mills

The normal operation of wet ball mill relies on the motor driving the ball mill to rotate. The motor drives the ball mill through an elastic column pin coupling, directly connecting the small gear, and driving the large gear to transmit the rotation of the ball grinding machine. During operation, if severe vibration occurs in the small gear and its base, it is mostly due to the far distance between the small gear and the anchor bolt, a lack of fixed point in the middle causing a large amplitude of the base of the small gear, and frequent vibration can cause serious wear of the small gear.

Solution

Replace the small gear of the ball mill and add two anchor bolts on the inside of the small gear meshing side with the large gear to re-strengthen the base. After the operation, clean the foundation first and check the levelness, elevation, position, and height of the anchor bolts on the foundation surface. Install anchor bolts with a drilling diameter of 100mm and grout, and then use a wedge to perform preliminary leveling. Then adjust the clearance between the small gear and the large gear, level the small gear by adjusting the height of the wedge, and grout again for a second time. Retain the semi-coupling on the motor side and survey the small gear shaft, and redesign and make the semi-coupling for the small gear end.

Because the semi-coupling at the small gear end is a tight fit with the shaft, it needs to be hot-fitted. First, make a trial bar that is 20μm larger than the upper limit of the shaft, fix the small gear shaft, and then heat the semi-coupling shaft hole. When the trial bar can pass through the semi-coupling shaft hole completely, it can be assembled. Put the small gear shaft and bearings into the bearing seat, adjust the tooth top clearance and tooth side clearance between the small gear and the large gear. Then grout for the second time between the base and the ground, and run a test after the grout sets. If you want to reduce the vibration fault of the small gear of industrial ball mills, you can install the ball mill grinding machine according to this method.

Cracking of large gear ring in industrial ball mills

If the ball mill vibrates suddenly and the noise becomes louder after a long-term operation, it is likely that the ball mill has serious cracks. When wet ball mills have minor cracks in the large gear ring, it should be remedied in time. Otherwise, in the case of long-term heavy-load operation, this situation will occur, which is a fatigue crack.

• If other parts of the large gear ring are intact and only severe cracks occur locally, local repair can be carried out. Before repair, all steel balls, materials, and other contents inside the ball mill cylinder must be removed. Then loosen the bolts of the large gear ring, find the crack, and weld two steel plates with the same size as the crack on both ends of the large gear ring face.

• If the large gear ring crack is severe or even broken, it needs to be removed and a new large gear ring needs to be installed.