Mining Drills
Probably one of the most common pieces of mining equipment, drills are an important part of the underground mining operation. Underground mining is carried out when rocks or minerals are located at a fair distance beneath the ground. But then they need to be brought to the surface. Underground specialized mining equipment such as trucks, loaders, diggers etc. are used to excavate the material and are normally hauled to the surface with skips or lifts for further processing. Drilling is normally required to place explosive charges to liberate the minerals from the overburden material. Underground mining techniques have progressed significantly over the past years, including using remote controlled machinery.
Drills assist in creating holes descending underground. If miners are required to work underground, drills can also be used in ensuring the holes are large enough to serve as a portal for miners to enter. Directional drilling is also a type of mining technology where miners will use the tools and certain methods to drill wells.
Overview of Ball Mills
As shown in the adjacent image, a ball mill is a type grinding machine that uses balls to grind and remove material. It consists of a hollow compartment that rotates along a horizontal or vertical axis. It’s called a “ball mill” because it’s literally filled with balls. Materials are added to the ball mill, at which point the balls knock around inside the mill.
How a Ball Mill Works
Ball Mills work by using balls to grind materials. Materials such as iron ore, pain and ceramics are added to the ball mill. Next, the ball mill is activated so that it rotates — either on its vertical or horizontal axis. As the ball bill rotates, the balls bounce around while striking the enclosed material. The force of these strikes helps to grind the material into a finer, less-coarse medium.
For a ball mill to work, critical speed must be achieved. Critical speed refers to the speed at which the enclosed balls begin to rotate along the inner walls of the ball mill. If a ball mill fails to reach critical speed, the balls will remain stationary at the bottom where they have little or no impact on the material.
No industry puts its Pumps through the ringer quite like mining. When the price of commodities such as gold spike in the short term, there is no time to lose--companies have to act fast to extract whatever they can as quickly as possible. While this flurry of activity is great for stockholders, it is not ideal for equipment. Many pumps end up falling prey to a myriad of problems that range from corrosion to being crushed by heavier machinery. To protect mine dewatering pumps to the fullest extent, consider these six common threats that pumps may encounter during mining operations.
In the mining industry, Hydrocyclones are mineral processing equipment used in slurry pulps to separate coarse and fine particles according to their size and density. The mixture [slurry pulp] is injected into the hydrocyclone in such a way as to create the vortex and, depending upon the relative densities of the two phases, the centrifugal acceleration will cause the dispersed phase to move away from or towards the central core of the vortex.
Coarse particles exit the bottom of the device (underflow) while fine particles are carried by the central air column and exit at the top (overflow). In metal processing applications, the product stream is the overflow (fine particles) and is typically sent to flotation circuits. The product stream is the underflow (coarse particles), as fines are separated from the final product as a means of quality control.
While under certain conditions roping and plugging can occur where the hydrocyclones ceases to classify the particles, the shapes of the discharge are visibly different than normal operating conditions.
The roping condition occurs when the amount of solids in the underflow increases to such a point that its discharge velocity is limited, resulting in the accumulation of coarse solids in the separation chamber. This mass passes through the vortex, causing the inner air core to collapse and the discharge at the apex to take the form of a solid stream (rope) consisting of coarse material with high solids density. Roping conditions reduce recovery rates and efficiency in metals processing and lead to quality losses in copper processing.