If you are wondering how a Ball mill works, this article is for you. We’ll cover the design, function, and repair of a trunnion. Keep reading to learn more. We’ll also discuss some of the common reasons why ball mills need to have a trunnion. It is important to know how trunnions are designed and how they function.

Ball mill trunnion

The trunnion of a ball mill undergoes uneven thermal effects due to its long-term operation. This wear and tear results in various defects on the cylindrical surface of the trunnion. These defects reduce the working capacity of the ball mill and require long downtime for repair. However, a study of the stress-strain state of the trunnion will provide a way to restore the cylindrical surface of the trunnion.

The trunnion acts to prevent solid particles from falling out of the machine. The material to be ground is fed into the machine through a 60-degree cone and discharged through the other side of the trunnion. When the drum rotates, the balls rise and drop and fall down the shell. The impact of the falling balls causes solid particles in between the ball and ground to be reduced in size.

Ball mill trunnion design

The trunnion design is an important factor for the operation of a ball mill. The trunnion must be strong enough to withstand the alternating stress during operation. The mill shell is generally made of rolled mild steel plates buttwelded together. Slots are drilled in the shell for bolts that hold the liners in place. The head is often equipped with heavy flanges that bolt on over the mill shell.

Ball mills are an important part of mining operations and play a major role in ore comminution circuits. However, due to improper design, manufacturing, and operation, flaws can occur. To avoid this, the trunnions must be carefully inspected for cracks and fracture mechanics. Fortunately, these flaws can be identified and measured through periodic inspections. Fortunately, the process is fairly simple.

Ball mill trunnion function

The trunnion in a Ball Mill is responsible for discharging material from the mill through the outlet side. When the helix angle is greater than the angle of repose, the balls will roll down, while a smaller helix angle causes the balls to rise. The trunnion’s mass flow rate is dependent on the comminution index W. The smaller the Rf, the greater the maximum power reduction and vice versa.

A ball mill is a type of grinder that is used to grind and blend a variety of materials. It grinds or crushes these materials using the impact and attrition of balls that fall from above into a rotating drum. The media is either solid or semi-solid and can vary in size, allowing it to produce various nanostructures. The number of balls and the type of material used to create the balls will determine the size of the nanostructure.

Ball mill trunnion repair

Due to the geometry of the bearing housing, the lower half of the ball mill trunnion was only approximately accessible for repair. The design criteria established the distance between scalloped areas. A two-phase repair procedure was proposed, the first phase of which involves cutting out the existing cracks and reaming the trunnion. In the event that too much metal is removed from the trunnion, a two-phase repair is required.

The initial cracks in the trunnion were caused by the slurry racing, which resulted in an uneven surface. The second crack extended through the journal surface. The trunnion’s journal bushing suffered from a stress over the yield strength of the metal, but the mill operator had a fault that allowed the trunnion to run without any oil film. This deterioration required extensive repair, and the mill was put back on line 30 hours after the cracks were discovered.