Influencing Factors of Tumbling Mill Working Capacity
Tumbling mill is also known as a ball mill or rod mill. They are all composed of a cylindrical cylinder lying horizontally on the bearing, and the material is ground into powder by rotating the cylinder. When we want to discuss the factors that affect the tumbling mill working capacity, we must first know the working principle of the tumbling mill.
Tumbling Mill Principle
A certain proportion of grinding media is added to the cylinder of the tumbling mill (the grinding media of the ball mill is steel balls, and the grinding media of the rod mill is steel rods or steel sections) and the material to be ground. After the tumbling mill working starts, the motor drives the bearing to rotate, and the cylinder rotates at a certain speed. Driven by the tumbling movement, the steel balls, and materials in the cylinder are lifted, thrown off, and ground into powder in the process.
Many factors are involved in the tumbling mill working process. Among them, the material to be ground, the grinding medium in the cylinder, and the operation of the tumbling mill itself will all affect the productivity of the tumbling mill, which will be described in detail below.
Influencing Factors of Production Capacity in the Tumbling Mill Working Process
Properties of the material to be ground
The hardness, toughness, dissociation and structural defects of the original ore determine the difficulty of grinding. If the grindability is small, the ore is easy to grind, the wear of the tumbling mill liner and the steel ball is small, and the energy consumption is small. Otherwise, the situation is just the opposite. The properties of the original ore directly affect the tumbling mill working capacity.
In the tumbling mill working process, if the ore is difficult to grind or needs fine grinding, new processing technology can be used to change the grindability of ore if the economy and site conditions permit.
- One method is to add some chemicals in the grinding process to improve the grinding effect and improve the grinding efficiency.
- Another method is to change the grindability of the ore, such as heating the ore, changing the mechanical properties of the entire ore, and reducing the hardness.
In addition, it can be known from production practice that the coarser the feed size of the material to be ground, the lower the working productivity of the tumbling mill. Therefore, the tumbling mill should strictly control the particle size of the feed material during its work. For the material in the crushing process, strict control should be achieved. For the raw materials that do not meet the feed size of the tumbling mill, they should be returned to the crusher and crushed again. Material particles that are too large will not only affect the output of the tumbling mill but also damage the liner in the cylinder and reduce the service life of the ball mill.
The filling coefficient of the grinding medium
In the tumbling mill working process, the grinding medium plays the role of grinding and impact in the cylinder at the same time. The quality of the finished product depends largely on the grinding medium. The more grinding media added to the cylinder, the more times the material is ground per unit time, and the higher the ball milling efficiency. However, too much grinding medium will occupy the effective space in the barrel of the tumbling ball mill, which will reduce the grinding efficiency. This requires a certain ratio between the grinding medium and the material, which is the filling coefficient.
Valid data shows that the suitable loading degree of the tumbling ball mill is 80%-90% of the total volume. Generally, the total load should not exceed five-quarters of the total capacity of the tumbling ball mill. Therefore, grinding steel balls generally account for 45%-55% of the total volume. In this range, the tumbling ball mill has the strongest working capacity.
In addition, the shape and quality of the grinding media will also affect the grinding efficiency. The short cylindrical steel section is more suitable for grinding, while the spherical grinding body is more suitable for impact-based crushing. Customers can choose according to the nature of the material, or send an inquiry to our technical experts.
To ensure the stability of the working environment of the tumbling ball mill is a necessary condition to ensure the working capacity of the tumbling ball mill. First, the material conveyed into the tumbling mill should be uniform. When the feed rate is too high, the particle size of the grinding material will become coarse and may cause “bulging”. At this time, we should stop feeding and make appropriate adjustments. It is recommended to use a vibrating feeder for feeding. Secondly, it is necessary to ensure that the ball mill has a good power supply and the bearing motor is driven normally to avoid sudden power failure or shutdown failure. Finally, whether it is dry grinding or wet grinding, the normal operation of the dust removal system and the water supply system should be ensured. All of the above factors will have an impact on the tumbling mill working capacity.