Cable lines are used in many sectors, including mining. However, their proper selection is necessary, you must take into account primarily construction and operation costs. You need to find a compromise between the lowest possible investment price and a reduction in energy loss.

Why is cable lines used in mining?

Cable lines are a key part of the power installation in mines, but the relatively high costs of investment and operation make them a considerable burden on the budget. So you need to consider the selection of components, especially since the high life of the cable line means investment for years. Cable lines ensure safety and low risk of failure, but you need to analyze the economic considerations well so that the cost of operation does not become too much for the mine. When designing, energy losses are often omitted, which can be from 8 to 15%from the moment it is produced to the recipient.

What are the costs of using cable lines?

The basis for control over investment costs, of course, is the use of correct laying technology to avoid damage to cables. Therefore, equipment such as a cable trailer is used, thanks to which the drums can be safely transported. Some proposed methods of reducing energy losses, such as the use of high conductive materials or cables with a large cooling area, are unfortunately difficult to implement in practice. It is therefore focused on increasing the transmission network voltage and improving the power factor.

It is difficult to precisely predict operating costs, because there is no certainty as to future energy prices and cable load. In addition, they depend on many factors, above all:

• Power loss during current flow through working veins,
• Dielectric losses in insulation,
• The need for maintenance, repair and renovation of the cable line,
• The cross -sectional of working veins - the greater the cross -section, the higher the cost of purchase, transport, cable and accessories. At a larger cross -section, the costs associated with the load on the load are falling.

Selection of cable lines in mining

The choice of cable should be a compromise between all factors that are worth considering. The first of them is usually long -lasting current load, depending primarily on the cable structure, resistance, cross -section and the material of vein construction and the permissible temperature of the insulation material. Regardless of the size of the power cable, the cable scissors are used to cut it to cut the veins safely and precisely. The load on the load is less affected by, for example, the room temperature. In mining, mainly power cables are mainly used with working copper veins and insulation from Polwinit or saturated polyethylene.

Although the cost of the current flow, the cost of current flows fall, a cable with the smallest possible veins, can be used to be used at a specific load. This provides many benefits: a lower price of the cable, easy transport and laying, low cost of accessories and possible repairs, as well as lower exposure to earthwathy currents. Cables with a small cross -section of working veins have a smaller weight, outer diameter and a radius of flexion. When laying them, e.g. fiber for cables is still used, but it is much easier. However, you have to reckon with the fact that during 20-30 years of cable operating, significant electricity losses will gather, which are quite significant with a small vein cross-section cables.

What do energy loss in cable lines depend on?

Of course, energy losses are not dependent only on the cross -section of working veins. They result from dielectric losses in insulation and heat formation in working veins when the load flows. Heat, to a lesser extent, also arises in other conductive elements, e.g. screens and armor. In working veins, losses vary depending on the resistance and the value of the load. In a small section, the resistance is higher, which leads to larger losses. That is why, in mining, power cables with copper working veins are used to reduce energy losses as possible. It is also saving the use of cables with saturated polyethylene insulation, because the dielectric loss factor is only 0.004 for this material, and for Polwinit - 0.1.

The cost of electricity losses, of course, depends on the current power price. It happens, however, that after a few years of operation, loss costs exceed the initial price of buying a cable. Interestingly, power cables can be included in fixed assets, which is why they are subject to depreciation write -offs. The annual costs of using the cable line result from depreciation, maintenance of lines and energy losses. It is assumed that the maintenance of the line, including Possible repairs are about 1% of the cost of buying a power cable. The depreciation rate can be taken at 8%, although it depends on the market situation and the time of use of the cable line.

The power infrastructure is so important in the mining industry that the wrong selection of the cable may be associated with really high costs, which is why detailed calculations are necessary.