Discussion on the production method, efficiency and use of medium-voltage cable

As we all know, wire and cable is a large class of electrical products
used to transmit electricity, transmit information and realize electromagnetic energy conversion.
With the advancement of science and technology, the production of medium voltage cables has become popular, but I have the following three points to discuss:

(1) How is medium voltage cable produced, and what are the production methods?

(2) What factors affect the production efficiency of medium voltage cables?

(3) What are the places where medium-voltage cables are used and as what lines?

In response to the first problem, the voltage level range of medium voltage cables: 6-35kV, at present, major domestic cable factories, including our own company, basically use catenary units, three-layer co-extrusion to produce medium voltage cables (cross-linked cables).

。 At present, there are four ways to produce cross-linked lines: horizontal, inclined, catenary, vertical, of which the most conducive to the production of medium voltage cables is vertical, followed by catenary, inclined, horizontal, but because the vertical type has higher requirements for the plant, and the laying cost is particularly large, in comparison, although the catenary type is not as good as the vertical type in the problem of wiping the pipe, but it can also be effectively controlled, therefore, major companies are using the catenary type to produce medium voltage cable
.

For the second problem, the basic structure of medium voltage cable: conductor - inner shield - insulation - outer shield, so, the first factor affecting production efficiency is the amount of rubber output of three extruders, the screw diameter of our company's three extruders is φ80, φ175, φ100; The second factor is the length and temperature of the pipeline, the length of the pipeline is basically nine or ten vulcanized pipes at present, and the length of the pipeline is basically fixed; Temperature is an important condition affecting polyethylene modification, so it has become the most important constraint on the production speed of medium voltage cross-linked line, the third factor is pipeline pressure, because pressure is also an important condition for polyethylene modification, pipeline no pressure, will lead to the reaction of the insulation layer of the back products can not be discharged, out of the pipeline will appear a lot of pores, so the pressure must have
.
These are most of the factors
that mainly affect production efficiency.

For the third problem, the medium-voltage cross-linked line is generally used in places where power transmission and transmission information flow is large because of the high voltage level, and it can be used in the distribution of the urban power grid, and the overhead lines of the urban network are changed to buried laying, which is safer and more reliable in comparison and has low
losses.
It can also be used for long-distance transmission cables in power stations, because the output power (P) of the power station is the same, according to the formula:

P=U*I

U - transmitted voltage, I-transmitted current

Under certain power conditions, the voltage becomes larger and the current becomes smaller, so the loss of the circuit becomes smaller, so the transmission with medium voltage cross-linked wire is chosen
.