In every underground mining facility, each component of the shaft must be able to carry out its respective functions efficiently for the whole operation to succeed. Among the components of note are the skips. As Britannica explains, mine skips act as shaft conveyors for transporting gathered ore from underground to the surface. This equipment is also used for transferring waste rock and debris for disposal.
Today, skip loading is usually automated along with dumping and ore hoisting systems. Two systems can be used for this purpose: volume-based or load-based measurement. The volume-based set-up is ideal for mines that harvest material of uniform density, with the occasional waste rock having lower density than the ore. If the harvested material is not uniform, volume-based measurement may cause overloading on the hoist, which would pose a significant risk. In such cases, the load-based method is necessary.
Demands on the Skip
Lifting large volumes of materials from the depths of underground mines is a struggle against gravity. It involves carrying dense rock in massive quantities, which equates to immense levels of strain on any equipment used. As such, mining skips must have extraordinarily rugged specifications to maintain efficiency and safety in the excavation process.
The skip must be able to carry large loads without being too heavy itself. Through the years, the mining industry has seen various developments in how skips are constructed, from the materials used to the design of the units. The use of aluminum alloys is pretty common because of the metal’s exceptional strength-to-weight ratio. The material’s downside is low-wear resistance, which is addressed by lining skips with abrasion-resistant steel, mild steel, or rubber.
The Encyclopedia of Life Support Systems (EOLSS) notes that the design used most often is the bottom-dump style, a lightweight but durable solution that can reliably transport medium to large loads. Other styles include the different types of front-dump skips, arc gate style skips, and Kimberly skips.
These factors give a glimpse of how the demands on skips can vary from one mine to the next. Leading producers such as Wabi Iron & Steel Corp. feature a strong focus on custom- design of skips and other mining components. Such versatility allows these manufacturers to satisfy almost any need.
Underground mining, Britannica.com
Underground Mining Transportation Systems, EOLSS