Electric cable business is actually a manufacturing organization of simple gear and fundamental product. Which is described as the "blood vessels" and "nerve" in the national economy, it's used for transmitting information and electricity and is indispensable for the electrification on the future, cable business is really a massive and supporting sector, items have to meet the needs of the primary industry, the improvement of major sector will promoted the improvement of cable sector.
1、What is Electric Cable?
Cable is a type
of wire products what's composed of a number of or a number of groups of
conductors twisted into a rope, every group of wires is insulated, and usually
revolve about a center rope, all of these are covered using a highly insulating
layer. Wire and cable is utilized in electric energy, communication and media
associated transmission purposes.
The basic structure
of cable consists of 4 components: core, insulation, shielding layer and
protective layer
(1) wire core
wire core is conductive a part of cable, that
is utilized for conveying power, is the primary a part of the energy cable.
(2) the
insulation
Insulation
insulates the core、the earth and
the diverse phase of wire core from one another, assure the electric power
transmission, it is an integral a part of cable structure.
(3) shielding
layer
the 15 kv and
above have conductor shielding layer as well as the insulating shield typically
.
(4) the part in
the protective cover
protective cover is used to safeguard the
energy cable in the the invasion of the impurities and moisture, and avert the
external force harm the power cable directly.
3、Different Classification According to Distinct Types
1) according to
the existing form: communication cable, direct existing cable; 2) in accordance
with the installation location: Overhead Power Cable, underground cable(May be laid
at indoor, tunnel and tube .Cable cannot beneath take mechanism outside force),
submarine cable (across the river,submarine cable). 3) in accordance with the
conductivity of wire core: ordinary cable, cryogenic and superconducting cable;
4) according to the amount of conductive wire: single core wire(a lot of types
for example Single core rigid conductor nonsheathed cable、Copper core PVC insulated wire））and multicore cable including 2 core
wire, 3 core wire, 4 core wire, five, six core wire and above,what are suitable
for the wiring of electrical controlling equipments and instrument,monitoring
and controlling return circuit. 5) Based on the insulation components, can be
divided in to the oil impregnated paper insulating power cable, plastic
insulated power cables, rubber insulated energy cable, for the plastic
insulated energy cables,, the frequently employed plastic cable is
polyethylene, crosslinked polyethylene and Pvc
Insulation Wire. Plastic cable structure is basic and
easy to manufacture, at the same time, with the characteristic of light weight,
simple installation. As a result it is widely applied in medium and low voltage
cable, even though its biggest drawback is the phenomenon of dendronized
breakdown , which limits the use for higher voltage.
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