Mine cable types, performance and use environment

(a) armored cable

Armored cables are armored with steel wire or steel tape. Steel wire armored cable is mostly used in vertical shafts or steep inclined roadways, while steel armored cables are mostly used in horizontal or gently inclined roadways. Among them, some cables pre-dripping the impregnant between the interphase and the paper-wrapped insulating layer, ie, the “dry-insulated” cable; and some cables use a special impregnating agent, and the impregnating agent will not be in the lead-bag at room temperature. Flow, which is a "no trickle" cable. These two types of cables are suitable for wellbore wells.

In the downhole, armored cables are mostly used to power stationary or semi-fixed devices. The biggest advantage of skid-mounted cables is the high dielectric strength of paper, so it is suitable for high-voltage cables, and its mechanical strength, heat resistance and safety are good. The disadvantages of the armored cable are the large bending radius, inconvenient movement, troublesome installation, and high level of technical requirements for cable joints and end caps.

(b) Rubber cable

Rubber cable can be divided into common rubber cable and shielded cable.

The shielded cable is mainly used in the working area of ​​the mining area to improve the safety of the work. The shielded cable and the common rubber cable are basically the same in construction. The difference is that the sheath of the ordinary rubber sheath is covered with a shielding layer, and a rubber outer sheath is added outside the shielding layer. The shielding layer is made of semiconductor material or copper wire nylon mesh.

The shielded cable overcomes the shortcomings of phase-to-phase short-circuits caused by the insulation failure of the main cable. The shielding layer is grounded, and the main core wire first hits the shielding layer, causing a ground fault, causing the leakage detection device to operate and shutting off the power supply, so it will not cause serious interphase short circuit accidents. Another advantage of the shielded cable is that it avoids the danger of electric shock due to cable damage. Because when the insulation of the main cable of the cable is damaged, it first hits the shielding layer, causing a ground fault, which cuts the power supply in advance and ensures personal safety. In addition, the combination of the shielded cable and the leak detection relay has the function of cutting off the fault line power in advance, which can effectively prevent the occurrence of leakage spark or short circuit arc. Therefore, it is particularly suitable for places with gas or coal dust explosion risk and frequent moving electricity. equipment.

(three) plastic cable

The core cable insulation and sheathing of plastic cables are all made of plastic. This type of cable is similar to armored cable if it is externally mounted and is similar to rubber-wrapped cables without armouring.

The advantage of plastic cables is that they allow high working temperatures, good insulation properties, corrosion-resistant sheaths, and unrestricted drop placement. Therefore, they should be used where possible.