CN206004276U - A kind of closed-entry cable passage - Google Patents

Abstract

A shrinking cable channel is used to successfully complete the channel layout in a limited space, and at the same time facilitate operation and maintenance and improve the utilization rate of the cable channel. It includes a cable ditch surrounded by cable ditch brackets, characterized in that the top of the cable ditch bracket is a closed structure, the top of the cable ditch is provided with a constriction, the upper part of the constriction is small, and the lower part is large. The small end of the constriction is provided with a cable trench cover, and the cable trench cover is located between two switch cabinets or between the switch cabinet and the wall. This passage is convenient for personnel to operate upright, saves space for construction and inspection passages, and effectively reduces the depth of cable passages; at the same time, a reasonable vertical distance is left to ensure convenient operation for personnel and normal transfer of cables, making cable entry more direct, convenient and fast . There is no need to configure auxiliary facilities such as ventilation, lighting, and fire prevention, which saves engineering investment.

Description

A shrinking cable channel

technical field

The utility model relates to the technical field of cable structures, in particular to a necking type cable channel.

Background technique

my country's land resources are scarce. In most parts of the country, the 10kV and 35kV power distribution devices of newly-built 220kV and below substations mostly adopt the form of indoor switchgear layout. The switchgear layout can be divided into two types: single row layout and double row layout. The conventional forms of cable structures serving indoor switchgear equipment mainly include three types: cable half-layer, cable trench and cable tunnel. In actual engineering design, some design schemes are considered from the perspectives of overall planning, economy, practicability, and construction difficulty. It is not allowed to set up a half-layer cable, and only the design scheme of cable trench and cable tunnel can be considered. At present, the construction of substations is gradually developing in the direction of compact substations. Some substation switchgear rooms are very tight. For conventional cable trenches, the cover plate must meet the requirements of easy opening, so it cannot be arranged under the equipment, and most of the switchgear equipment has a large number of cables. , The diameter is large, which puts forward higher requirements on the capacity of the cable channel, and considering the impact of building foundation collision and other factors, in some design schemes, the indoor space of the switch cabinet does not meet the conditions for setting up conventional cable trenches. In this case, cable structures can only be arranged in the form of cable tunnels. "Code for Design of Electric Power Engineering Cables" (GB 50217-2007) has detailed rigid requirements for the height of cable tunnels and the width of inspection channels. The cable tunnel arranged in accordance with the requirements of the code is deep and wide, and needs to be equipped with a complete set of auxiliary facilities such as lighting, fire protection, drainage, and ventilation. The project investment is large, and the utilization rate of the internal space of the cable tunnel is not high. Big waste.

As shown in Figure 1, it is a double-row arrangement of 10kV switchgear. It can be seen from the figure that in the double-row arrangement of switchgears, the shortest distance between the "back-to-back" of the switchgear is only 1000mm, and the primary cable in the channel The diameter is large and the quantity is large, and in order to ensure the cable turning radius requirements, the depth of the trench must be greater than 1000mm. Then, according to the requirements of the specification, the maintenance channel in the trench must not be less than 600mm (one-sided support), and the final installation space of the cable support is only 400mm. The impact of the angle steel used for bracket fixing and the overhanging eaves at the end on the cable laying (occupying about 100mm of the bracket width), resulting in insufficient space for cable laying in the cable structure, which cannot meet the cable laying requirements. To sum up, in this case, the 10kV cable channel is generally laid in a cable tunnel, and is laid under the switch cabinet. Figure 3 shows the cable layout when the cable peak flow is present. Idle, the idle rate reaches 25%, causing a lot of waste. At the same time, the construction of the cable tunnel is complicated. Compared with the cable trench, it needs to be equipped with a complete set of auxiliary facilities such as lighting, fire prevention, drainage, and ventilation. The layout of the cable tunnel in the conventional scheme increases the project cost. Investment is not conducive to the economic management of infrastructure project assets.

As shown in Figure 2, for the single-row arrangement of 35kV switchgear, according to the "Technical Regulations for Design of High-Voltage Power Distribution Devices" (DL/T 5352-2006), the maintenance channel in front of the 35kV switchgear must meet "(single vehicle length + 1200) mm” requirements, surveyed several 35kV switchgear manufacturers who have recently won the bid, the maximum length of the single vehicle can reach 1400mm, then there must be at least 2600m of space in front of the cabinet, the length of the switchgear is 2800mm, and the practical width of the 35kV switchgear room is 6600mm. The space is only a space of 6600-2800-2600=1200mm width. If the cable channel is arranged in a cable trench, since the cable trench cover plate needs to meet the requirements of easy opening, the switchgear cannot block the cable trench cover plate and can only be arranged in a space with a width of 1200mm. At the same time, for buildings with half-story buildings without cables, the foundations of the structural columns are mostly independent foundations, so a certain distance must be kept between the cable channels and the structural columns to avoid collisions between the cable channels and the structural column foundations. Some factors and the thickness of the cable trench wall finally lead to the fact that the inner width of the cable trench that can be used is less than 800mm. The 35kV switchgear has a large diameter and a large number of primary cables, and in order to ensure the cable turning radius requirements, the depth of the trench must be greater than 1000mm, and then the maintenance channel in the trench must not be less than 600mm (one-sided support), and the final installation space for the cable support is only 200mm. Considering the impact of the angle steel used for fixing the bracket and the overhanging eaves at the end on the cable laying (about 100mm of the bracket width), the cable channel is seriously insufficient and cannot meet the cable laying requirements. To sum up, the 35kV cable channel of the conventional scheme is generally laid in a cable tunnel, and is laid under the switch cabinet. Figure 4 shows the cable layout at the peak flow rate of the cable. Idle, the idle rate is as high as 33%, causing a lot of waste. At the same time, the construction of the cable tunnel is complicated. Compared with the cable trench, it needs to be equipped with a complete set of auxiliary facilities such as lighting, fire prevention, drainage, and ventilation. Investment is not conducive to the economic management of infrastructure project assets.

Utility model content

The purpose of the utility model is to provide a necked cable channel, which is used to successfully complete the channel layout in a limited space, and at the same time facilitates operation and maintenance, and improves the utilization rate of the cable channel.

The technical solution adopted by the utility model to solve the technical problem is: a necked cable channel, in which a cable trench support is provided, and the feature is that the direct upper part of the cable trench support is a closed structure, The top of the cable trench is provided with a constriction, the upper part of the constriction is small and the bottom is large, and a cable trench cover is provided at the small end of the constriction, and the cable trench cover is located between two switch cabinets or the switch cabinet between the wall.

Further, for the double-row arrangement of switch cabinets, the cable trench cover plate is arranged between two switch cabinets.

Further, for a single-row arrangement of switch cabinets, the cable trench cover is arranged between the switch cabinet and the wall.

The beneficial effects of the utility model are: the necked cable channel provided by the utility model has at least the following advantages:

(1) Considering that the construction and operation and maintenance personnel are located in the construction and inspection passage area of the cable structure when working, the new "shrinking type" cable structure construction and inspection passage is directly above the cable trench cover, which is convenient for personnel to operate upright and saves construction and labor costs. Patrol channel space, and effectively reduce the cable channel depth;

(2) The upper part of the cable support is designed as a closed structure, and a reasonable vertical distance is left at the same time to ensure the convenience of personnel operation and the normal transfer of cables. This closed structure has a cable lower hole, which can be arranged under the switchgear equipment. More direct, convenient and fast.

(3) Since the "retracted" cable channel is a non-fully enclosed structure, there is no need to configure auxiliary facilities such as ventilation, lighting, and fire protection, which saves engineering investment.

(4) Compared with the conventional tunnel scheme, the design scheme of the shrinking cable structure is not limited by the height of the passage. The width of the construction and inspection passage can also refer to the standard of the conventional cable trench, and the length and width of the shrinking cable passage can be flexibly adjusted according to the cable capacity. The size and internal space utilization rate are much higher than the conventional cable tunnel layout scheme, which basically solves the problem of idle internal space, and the section of the cable channel is significantly reduced, which greatly saves the project cost.

Description of drawings

Figure 1 shows the double row arrangement of 10kV switchgear;

Figure 2 shows the cable layout when the peak flow rate of the cable channel is 10KV;

Figure 3 shows the single row layout of 10kV switchgear;

Figure 4 shows the cable layout at the peak flow rate of the 35KV cable channel;

Figure 5 is a double-sided necking type cable channel;

Figure 6 is a single-sided shrink-type cable channel;

In the figure: 1 cable support, 2 cable trench cover, 3 cable trench, 4 cable trench support.

detailed description

"Code for Design of Electric Power Engineering Cables" (GB 50217-2007) has detailed rigid requirements for the height of cable tunnels and the width of inspection channels. The inner height of the cable tunnel is not less than 1900mm, which is mainly to facilitate the cable laying construction and inspection and maintenance operations in the channel, so as to ensure that the construction personnel and operation and maintenance personnel can operate upright. At the same time, because the tunnel is a fully enclosed environment, the width of the construction and inspection channel is also wider Some need to be equipped with a full set of auxiliary facilities. Since the cable tunnel is a fully enclosed structure, it has the advantage that it can be placed directly under the switch cabinet equipment. For the cable trench, since the upper cover can be opened, the operator will not be affected by the upright work after the cover is opened, so its height is not limited, and the width of the construction and inspection passage is relatively narrow, so there is no need to configure ventilation, lighting, fire protection, etc. Auxiliary facilities save investment, and their depth is directly determined by the number of cables in the trench, and the space utilization rate in the trench is high. The utility model integrates the advantages of the cable trench and the cable tunnel, and designs a "retracted" cable channel.

1. As shown in Figure 5, for the 10KV switchgear double-column layout: use double-sided necking type cable channels, and the part directly above the cable channel cable bracket 1 is designed as a closed part, but a reasonable vertical space is guaranteed to ensure the safety of the cables. Smooth laying and daily operation of operators, cable trench cover plate 2 is installed in the middle channel of the cable trench, which is located between the "back-back" of the switch cabinet, which can be easily opened and the entrance width is not less than the operation channel width (700mm), and the cover plate is uncovered Finally, the construction and operation personnel can move upright in the cable communication channel, and can successfully complete the cable laying and maintenance. The width of the "retracted" cable trench cover is smaller than the shortest distance between the "back-to-back" of the switchgear, so it can be opened smoothly.

By rationally allocating the cable space in the cable channel and adopting the shrinking cable trench, under the premise that the total amount of cables in the cable channel remains unchanged, the cross-sectional size of the cable channel is reduced from 2200mm×1900mm in the conventional tunnel scheme to 1900mm×1400mm in the cable trench scheme Compared with the conventional tunnel scheme, the width is reduced by 300mm, the depth is reduced by 500mm, the section is reduced by 36% compared with the conventional tunnel layout, the idle rate of the support is reduced from 25% to 0%, and there is no need to configure auxiliary facilities such as ventilation, lighting, and fire prevention, and the project cost is reduced by 49% %above.

2. As shown in Figure 6, for the 35KV switchgear single-row arrangement: use one-sided shrinking cable channel, and the one-sided shrinking cable trench cable support part 1 is designed as a closed part, but a reasonable vertical space is guaranteed. To ensure the smooth laying of cables and the daily operation of operators, the cable trench cover 2 is set on the right side of the cable trench 3, which is located between the back of the cabinet and the wall. After the cable trench cover is opened, the construction and operation personnel can move upright in the cable trench, and can smoothly complete the cable laying and maintenance. The width of the one-sided shrinking type cable trench cover plate is smaller than the shortest distance from the back of the switch cabinet to the wall, and can be opened smoothly.

By rationally allocating the cable space in the channel and adopting the shrinking cable trench, under the premise that the total amount of cables in the cable channel remains unchanged, the cross-sectional size of the cable channel is reduced from 1900mm×1900mm in the conventional tunnel solution to 1200mm×1600mm in the cable trench solution Compared with the conventional tunnel scheme, the width is reduced by 700mm, the depth is reduced by 300mm, the section is reduced by 47% compared with the conventional tunnel layout, the idle rate of the support is reduced from 33% to 0%, and there is no need to configure auxiliary facilities such as ventilation, lighting, and fire prevention, and the project cost is reduced by 57% %above.

Analysis and comparison table of cable channel layout:

The utility model integrates the advantages of the cable trench and the cable tunnel, and innovatively designs the shrinking cable trench.

(1) Considering that the construction and operation and maintenance personnel are located in the construction and inspection passage area of the cable structure when working, the new "shrinking type" cable structure construction and inspection passage is directly above the cable trench cover, which is convenient for personnel to operate upright and saves construction and labor costs. Patrol channel space, and effectively reduce the cable channel depth;

(2) The upper part of the cable support is designed as a closed structure, and a reasonable vertical distance is left at the same time to ensure the convenience of personnel operation and the normal transfer of cables. This closed structure has a cable lower hole, which can be arranged under the switchgear equipment. More direct, convenient and fast.

(3) Since the "retracted" cable channel is a non-fully enclosed structure, there is no need to configure auxiliary facilities such as ventilation, lighting, and fire protection, which saves engineering investment.

(4) Compared with the conventional tunnel scheme, the design scheme of the shrinking cable structure is not limited by the height of the passage. The width of the construction and inspection passage can also refer to the standard of the conventional cable trench, and the length and width of the shrinking cable passage can be flexibly adjusted according to the cable capacity. The size and internal space utilization rate are much higher than the conventional cable tunnel layout scheme, which basically solves the problem of idle internal space, and the section of the cable channel is significantly reduced, which greatly saves the project cost.

Claims (3)

1. A necking type cable channel, in which a cable trench support is provided, is characterized in that the top of the cable trench support is a closed structure, and the top of the cable trench is provided with a necking, the The upper part of the constriction is small and the lower part is large, and a cable trench cover is provided at the small end of the constriction, and the cable trench cover is located between two switch cabinets or between the switch cabinet and the wall. 2. A necked cable channel according to claim 1, characterized in that, for the double-row layout of the switch cabinets, the cable trench cover is arranged between the two switch cabinets. 3. A necked cable channel according to claim 1, characterized in that, for the arrangement of switch cabinets in a single row, the cable trench cover plate is arranged between the switch cabinet and the wall.