JPS608515Y2 - Lubricating connection of single-core corrugated aluminum OF cable - Google Patents

Description

[Detailed description of the invention] This invention uses normal connections (N, J) when lubricating a single-core corrugated aluminum sheathed OF cable, and attaches an oil tank to the connection. be.

Originally, with OF cables, it is necessary to keep the oil pressure in the cable system higher than atmospheric pressure and lower than the maximum allowable oil pressure, whether under constant continuous load or during transient times such as when the load is turned on or off. .

For this reason, various oil tanks are connected to the terminal portion of the OF cable to keep the oil pressure in the cable system within the permissible oil pressure range.

In general, the hydraulic pressure generated in a cable system can be broadly divided into two types. One is the hydrostatic pressure that is normally applied to each point in the cable system, which is the difference in oil head between the oil tank and each point in the cable system plus the pressure of the oil tank itself. The other is a transient oil pressure change that is proportional to the square of the oil supply section from the oil tank to each point on the cable system due to the expansion and contraction of oil that occurs in the cable system during transient periods.

Therefore, if the refueling section is long, the transient change oil pressure will be large,
It may not be possible to keep the oil pressure within the allowable oil pressure range.

In order to prevent such drawbacks, the oil supply section is shortened, and in order to minimize the transient change in oil pressure, an oil tank is connected to a junction box in the middle of the cable route in order to keep the oil pressure in the cable system within the permissible oil pressure range. It is.

However, in single-core OF cables, an insulating paper layer is provided around the conductor of the cable, so it is necessary to ensure smooth oil passage between the oil passage located at the center of the conductor and the oil tank provided outside the contact box. It was impossible.

Therefore, in order to allow oil to pass through to the outside of the insulator, oil supply junction boxes (F, J) or oil stop junction boxes (S, J) are made by providing slits in the insulating paper at the connection part to form oil passages. A fuel supply system was constructed by installing a box along the route and connecting an oil tank to the box.

However, because F, J, S, and J are expensive, it is not possible to economically design a refueling system, and if system change work is required, refueling must be done from a route other than F, J, S, or J. As a result, flexibility in cable system design was lost.

The present invention makes it possible to supply oil at the oil supply connection part of a single-core corrugated OF cable by using inexpensive and small N and J, without using F, J or S, J as described above. This is what I found.

That is, the present invention, when lubricating a single-core corrugated aluminum sheathed OF cable, installs a desired number of normal connections (N, J) in series at predetermined intervals on the cable, and connects the connections that require lubricating. It has an oil tank attached.

The present invention will be explained in detail based on the drawings.

FIG. 1 shows a cross-sectional view of a single-core corrugated aluminum sheathed OF cable.

Since a corrugated gap 9 exists between the insulating shield 6 and the corrugated aluminum sheath 7, this space functions as an external oil passage.

Therefore, as shown in the oil supply system diagram in Figure 2, a special junction box F
, J, S, J without using N, Jl 0. 10',
10"... are installed in series, and oil tanks 11.11',
11'', for example, by supplying oil to the corrugated gap 9 existing between the insulating shield 6 and the corrugated aluminum sheath 7 at intervals of 2 to 3 krIL.

Note that 13 is a terminal box. Therefore, N, which requires refueling,
To install an appropriate oil tank on J, supply oil to the gap between the connection part core and connection part case, and supply oil to the corrugated gap between the insulation shield and the corrugated aluminum sheathing. This enables extremely economical lubrication design when lubrication is required mid-route in long-distance, high-head cable systems, and the lubrication locations are not limited, allowing all N and J stations to be lubricated. Since this is a possible connection part, the oil pressure within the cable system can be kept within the permissible oil pressure range at all times.

In addition, if it is necessary to change the cable system, it is possible to supply oil from other N or J stations as long as there is space for installing an oil tank, allowing flexibility in cable system design.

For OF cables of 500KV or more, which are currently in the early stage of practical use, even if refueling is required from the middle of the route, manhole space is required, but S, J, F, and J, which require enormous development costs, are A cable system can be easily and compactly configured without using it.

As described in detail above, the present invention is of great practical importance, as it allows a cable oil supply system to be formed at low cost with a simple structure.

[Brief explanation of the drawing]

Figure 1 is a cross-sectional view of a single-core corrugated aluminum sheathed OF cable, Figure 2
The figure is a schematic explanatory diagram of the present invention. 1... Cable, 2... Hollow oil passage,
3... Division compressed conductor, 4... Binder, 5... Insulating paper, 6... Insulating shield,
7...Aluminum coating, bottom...vinyl anticorrosion layer, 9...corrugated gap, 10.10', 10''.
...Ordinary connection box, 11.11', 11''...
...Oil tank, 12.12', 12''...Oil supply pipe,
13...Terminal box.

Claims (1)

[Scope of utility model registration request] In a single-core corrugated aluminum sheathed OF cable, a desired number of ordinary junction boxes are installed in series at predetermined intervals of the cable, and an oil tank is attached to the ordinary junction box that requires oiling via an oil supply pipe, A single-core corrugated aluminum sheathed OF characterized in that the corrugated gap existing between the insulation shield of the single-core corrugated aluminum sheathed OF cable and the corrugated aluminum sheath is supplied with oil by lubricating the ordinary connection box. Cable lubrication connection.