Electric cable sector is really a manufacturing enterprise of fundamental equipment and fundamental product. Which can be described because the "blood vessels" and "nerve" of the national economy, it is utilized for transmitting information and electricity and is indispensable towards the electrification in the future, cable market is actually a big and supporting business, goods have to meet the needs from the principal sector, the development of principal industry will promoted the improvement of cable industry.
1、What is Electric Cable?
Cable is really
a kind of wire merchandise what exactly is composed of numerous or a number of
groups of conductors twisted into a rope, each group of wires is insulated, and
typically revolve around a center rope, all of these are covered with a highly insulating
layer. Wire and cable is utilized in electric power, communication and media
connected transmission purposes.
The basic
structure of cable consists of 4 parts: core, insulation, shielding layer and
protective layer
(1) wire core
wire core is conductive part of cable, which
can be utilized for conveying energy, is the major a part of the power cable.
(2) the
insulation
Insulation
insulates the core、the earth as
well as the distinct phase of wire core from one another, guarantee the
electric power transmission, it truly is an integral a part of cable structure.
(3) shielding
layer
the 15 kv and
above have conductor shielding layer and the insulating shield frequently .
(4) the part in
the protective cover
protective cover is used to defend the power
cable from the the invasion of the impurities and moisture, and stop the
external force damage the energy cable straight.
3、Different Classification In accordance with Diverse
Types
1) according to
the existing kind: communication cable, direct present cable; 2) based on the
installation place: Overhead Power Cable, underground cable(Might be laid
at indoor, tunnel and tube .Cable can not below take mechanism outside force),
submarine cable (across the river,submarine cable). 3) according to the
conductivity of wire core: ordinary cable, cryogenic and superconducting cable;
4) according to the amount of conductive wire: single core wire(numerous sorts
for example Single core rigid conductor nonsheathed cable、Copper core PVC insulated wire））and multicore cable such as 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. five) In line with the insulation supplies, can be
divided in to the oil impregnated paper insulating energy cable, plastic
insulated power cables, rubber insulated energy cable, for the plastic
insulated energy cables,, the frequently used plastic cable is polyethylene,
crosslinked polyethylene and Pvc Insulation
Wire. Plastic cable structure is basic and easy to
manufacture, at the same time, using the characteristic of light weight, simple
installation. For that reason it really is extensively applied in medium and
low voltage cable, even though its most significant drawback would be the
phenomenon of dendronized breakdown , which limits the use for greater voltage.
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