JPS6154810A - High thermal resistance trough - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a trough used for laying power cables within a tunnel.

Currently, the trough indirect cooling method is most commonly used for forced cooling of large-capacity cable lines in large cities.

As shown in "Figure 1", an FRP trough 12 is installed inside the tunnel lO, and a cable 14 and a water cooling pipe 1 are installed inside the trough 12.
6, and the heat generated by the cable 14 is carried away by the circulating water in the water cooling pipe 16.

By the way, the temperature inside a cave varies depending on whether people are working inside it or
40° so that regular patrols can be carried out.
It is necessary to suppress it to about C.

Originally, the power transmission capacity of a cable is determined by the temperature of the cable conductor (which varies depending on the type of cable insulation), but when many cables are installed in a tunnel,
Even though there is still room for cable conductor temperature, there is a phenomenon in which the temperature of the tunnel increases and restrictions are placed on it.

The object of the present invention is to provide a high heat resistance trough that can solve the above problems by reducing the amount of heat dissipated into the sinus.

As shown in "Figure 2" and "Figure 3" by Hatsuya Shido Ikisei, in the trough installed in the tunnel 10 and housing the power cable 14 and the water cooling pipe 16 for indirect cooling, It is characterized in that a heat insulating material 20 is placed inside, and the outside of the cable and the water-cooled pipe are surrounded by the heat insulating material.

In the case of "Fig. 2", a heat insulating sheet is used as the heat insulating material 20. In this case, the insulation sheet.

Its central part covers the water cooling pipe 16, its both sides hang down along the inner surface of the trough, and when its tip touches the spacer 18, it bends inward and reaches the bottom of the cable 14, connecting the cable 14 and the water cooling pipe It surrounds the outside of 16. Note that the heat insulating sheet may be omitted in the portions touching the spacer 18 by stopping when the tips of both side portions touch the spacer 18.

3 shows a case where a foamed roll plate is used as the heat insulating material 20, which is pre-formed and pasted on the inner surface of the trough body and lid.

By doing so, the amount of heat discharged to the outside of the trough is reduced due to the heat insulating material 20, and the temperature rise in the tunnel can be suppressed to a lower level than before.

Although more heat accumulates in the trough than in the past, this heat is carried away by the water in the water cooling pipe 16, so the cable conductor temperature does not particularly rise.

The following Table 1 shows the results when the trough shown in Figure 3 was used on the model line of the basal narrow tectorial bud shown in Figure 1. However, Cableno? 12JE 275kV cooling length
2.5 km Inlet water temperature 10°C Target power transmission capacity 5 GOMW/line Table 1 From this table, in the case of the present invention, compared to the conventional method, the conductor size needs to be 8800 mrn to obtain the same power transmission capacity.
It turns out that you can save some money.

1. In a trough installed in the ``+1!'' cable cable and a water-cooled pipe for indirect cooling, a heat insulating material is placed inside the trough, and the external force of the cable and water-cooled pipe is reduced by the heat insulating material. Since most of the heat generated by the cable is transferred to the water in the water-cooled pipe 16, the amount of heat released into the tunnel is greatly reduced.6 Therefore, the above-mentioned increase in power transmission capacity, or , it is possible to save on cable conductor size.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of conventional indirect cooling inside a trough. FIG. 2 and tfS3 are explanatory diagrams of different embodiments of the present invention. lO; Cave 12 Nidraf 14: Cable 16: Water cooling pipe 20: Insulation material

Claims (1)

[Claims] A trough that is installed in a tunnel and accommodates a power cable and a water-cooled pipe for indirect cooling, the inside of which is provided with a heat insulating material, and the cable and water-cooled pipe are surrounded by the heat insulating material. A high heat resistance trough characterized by: