KR101607882B1 - Installation device in manhole of underground transmission systems - Google Patents

Abstract

The present invention relates to an installation device of an underground transmission line for a manhole, which comprises: a support unit installed to be fixed to a manhole, and arranged between a connection unit for connecting a cable and a duct unit; and a fixing unit gripping the cable connected to the connection unit by passing through the duct unit, and installed to be fixed to the support unit, thereby reducing the size of the manhole by forming the cable with a linear construction.

Description

{INSTALLATION DEVICE IN MANHOLE OF UNDERGROUND TRANSMISSION SYSTEMS}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a manhole underground transmission line laying apparatus, and more particularly, to a manhole underground transmission line laying apparatus capable of replacing a curved line construction applied during a manhole in order to absorb cable thermal expansion and contraction.

In general, when the manhole size of underground transmission line is selected, Offset construction is applied to install the cable from the duct to the connection part in the manhole so that the expansion and contraction of the cable due to the temperature change (load) . This offset is an important factor in determining the size of the manhole, which greatly affects the life and stability of the cable. The length of the manhole is determined in consideration of the work space, the offset, and the design radius of curvature at the time of cable installation. The manhole width is determined in consideration of the distance between the cable and the manhole wall and the distance between the inlet pipe and the cable. At this time, the minimum offset is set so as to absorb heat expansion and shrinkage caused by the temperature change of the cable.

However, due to the offset construction in such a manhole, the manhole size is relatively large. As a result, the construction of the manhole is complicated due to the traffic disorder caused by overloading of the road, There are difficulties such as. Therefore, there is a need to improve this.

BACKGROUND ART [0002] The background art of the present invention is disclosed in Korean Patent Laid-Open Publication No. 2013-0051590 (published on May 31, 201, entitled "Manhole for underground burial installed with a curved tube channel body").

SUMMARY OF THE INVENTION The present invention has been made in order to solve the above problems, and it is an object of the present invention to provide a manhole ground transmission line installation device capable of reducing a manhole scale by constructing a cable straight, There is a purpose.

A manhole ground transmission line laying apparatus according to the present invention comprises: a pedestal portion fixed to a manhole and disposed between a connecting portion connecting a cable and a channel portion; And a fixing part which is fixed to the receiving part, the fixing part being configured to hold the cable, which is connected to the connection part, through the pipe part, and the cable is held by the fixing part and is linearly applied.

And the plurality of fixing portions are spaced apart from each other.

Wherein the fixing portion includes: a lower fixing portion which is seated on the receiving portion and in which a lower groove portion is formed to surround a lower side of the cable; An upper fixing part disposed above the lower fixing part and having an upper groove part to cover an upper side of the cable; And a fixed coupling portion coupling the upper fixed portion and the lower fixed portion and fixing the lower fixed portion to the receiving portion.

The size of the lower groove part decreases from one end to the other end of the lower fixing part and the size of the upper groove part decreases from one end to the other end of the upper fixing part.

Wherein the fixing portion comprises: a lower buffer portion disposed between the lower groove portion and the cable, the lower buffer portion including a buffer material; And an upper cushion part disposed between the upper groove part and the cable, the upper cushion part including a buffer material.

The lower projection formed on the lower cushioning portion is inserted into a lower insertion portion formed in the lower groove portion and the upper projection formed on the upper cushioning portion is inserted into an upper insertion portion formed in the upper groove portion.

The manhole ground transmission line laying apparatus according to the present invention is capable of constructing a straight line of a cable, thereby reducing the size of a manhole.

The manhole ground transmission line laying apparatus according to the present invention has a shape in which the size of the lower groove portion and the upper groove portion is gradually reduced so that a part thereof corresponds to the diameter of the cable, .

In the underground transmission line laying apparatus according to the present invention, since the lower cushioning portion and the upper cushioning portion wrap the cable, the cable can be protected by cutting off the contact between the cable and the metal object.

In the underground transmission line laying apparatus according to the present invention, since the lower projection is inserted into the lower insertion portion and the upper projection is inserted into the upper insertion portion, the insertion positions of the lower cushion portion and the upper cushion portion are guided, It can be prevented from being moved.

1 is a view schematically showing a state in which a manhole ground transmission line laying apparatus according to an embodiment of the present invention grasps a cable.
FIG. 2 is a view schematically showing a state in which a fixing portion is separated from a man-in-theground transmission line laying apparatus according to an embodiment of the present invention.
FIG. 3 is a schematic view illustrating a state where a fixing unit is coupled to a man-made underground transmission line laying apparatus according to an embodiment of the present invention.
FIG. 4 is a cross-sectional view schematically showing a state where the fixing portion is fixed to the receiving portion in the underground transmission line laying apparatus according to the embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of an underground transmission line laying apparatus according to the present invention will be described with reference to the accompanying drawings. In this process, the thicknesses of the lines and the sizes of the components shown in the drawings may be exaggerated for clarity and convenience of explanation. Further, terms to be described below are terms defined in consideration of functions in the present invention, which may vary depending on the intention or custom of the user, the operator. Therefore, definitions of these terms should be made based on the contents throughout this specification.

1 is a view schematically showing a state in which a manhole ground transmission line laying apparatus according to an embodiment of the present invention grasps a cable. Referring to FIG. 1, a manhole underground transmission line laying apparatus 1 according to an embodiment of the present invention includes a receiving portion 10 and a fixing portion 20.

The pedestal 10 is fixed to the manhole 100. A conduit 120 for guiding the cable 110 is formed on both sides of the manhole 100 and the cable 110 located in the manhole 100 is connected by the connection part 130. The pedestal 10 may be fixed to the inner wall of the manhole 100 and may be disposed between the connecting portion 130 and the channel portion 120. For example, when the connecting portion 130 is positioned at the center of the manhole 100 and the channel portion 120 is disposed at both sides of the manhole 100, the receiving portion 130 is provided between the connecting portion 130 and the channel portion 120 10, respectively.

The fixing part 20 passes through the conduit part 120 and grips the cable 110 connected to the connection part 130. The fixing part (20) is fixed to the receiving part (10). The cable 110 held in the fixed portion 20 can be straightened.

The cable 110 is constructed so that the cable 110 is curved in the horizontal direction in consideration of the amount of movement of the cable 110 due to the variation in the temperature of the cable 110. Therefore, The length of the cable 110 increases. However, when the fixing portion 20 grasps the cable 110 to reduce the axial force applied to the connection portion 130, the cable 110 can be linearly formed, the length of the cable 110 to be installed in the curved construction is reduced, The size of the cable 100 may also be reduced to correspond to the length of the cable 110.

A plurality of the fixing portions 20 are disposed apart from each other. For example, five fixing portions 20 may be disposed between any one of the channel portion 120 and the connection portion 130. Each of the fixing portions 20 may be coupled to the single receiving portion 10 or may be coupled to the receiving portions 10 corresponding to the respective fixing portions 20, respectively. At this time, the interval between the fixing portions 20 may be 500 mm or less.

FIG. 2 is a schematic view showing a state in which a fixing part is separated from a manhole ground transmission line laying apparatus according to an embodiment of the present invention. FIG. 3 is a perspective view of a manhole ground transmission line laying apparatus according to an embodiment of the present invention. FIG. 4 is a cross-sectional view schematically showing a state where the fixing portion is fixed to the receiving portion in the underground transmission line laying apparatus according to the embodiment of the present invention. FIG. 2 to 4, the fixing unit 20 according to an embodiment of the present invention includes a lower fixing unit 30, an upper fixing unit 40, and a fixing unit 50.

The lower fixing part 30 is seated on the receiving part 10 and the lower groove part 31 is formed so as to surround the lower side of the cable 110. For example, a lower groove portion 31 may be formed at the upper center of the lower fixing portion 30, and a plurality of lower coupling holes 32 may be formed at the edge of the lower fixing portion 30.

The upper fixing part 40 is disposed above the lower fixing part 30 and the upper groove part 41 is formed to surround the upper side of the cable 110. [ For example, an upper groove portion 41 may be formed at the lower center of the upper fixing portion 40, and a plurality of upper coupling holes 42 may be formed at the edge of the upper fixing portion 40.

The lower fixing part 30 and the upper fixing part 40 may be formed to be symmetrical to each other. When the lower fixing part 30 and the upper fixing part 40 are arranged to face each other, the lower coupling hole part 32 and the upper coupling hole part 42 can be arranged in a straight line.

The fixing part 50 engages the upper fixing part 40 and the lower fixing part 30. The stationary engaging portion 50 fixes the lower fixing portion 30 to the receiving portion 10. In this embodiment, the stationary engaging portion 50 may include a fixing bolt 51 and a fixing nut 52. The head portion of the fixing nut 51 extends over the upper fixing portion 40 and the body portion of the fixing nut 51 can penetrate the upper fitting hole portion 42 and the lower fitting hole portion 32. The lower end of the fixing nut 51 can pass through the receiving hole portion 12 formed in the receiving portion 10. The fixing nut 52 is located below the receiving portion 10 and can be screwed to the fixing bolt 51 passing through the receiving hole portion 12. [

The size of the lower groove portion 31 decreases from one end of the lower fixing portion 30 to the other end and the size of the upper groove portion 41 decreases from one end of the upper fixing portion 40 to the other end. That is, the lower trench 31 and the upper trench 41 may be formed to have a length in the longitudinal direction of the cable 110, and may have a width in the width direction of the cable 11. The widths of the lower groove 31 and the upper groove 41 gradually decrease or increase toward the longitudinal direction of the lower groove 31 and the upper groove 41, respectively. At this time, the width of the lower groove 31 and the upper groove 41 may mean the width of the recessed groove or the diameter of the surface forming the recessed groove. On the other hand, the narrowest portion of the lower groove 31 and the upper groove 41 may correspond to the diameter of the cable 110.

The fixing part 20 according to an embodiment of the present invention may further include a lower buffer part 60 and an upper buffer part 70. The lower cushioning portion 60 is disposed between the lower trench 31 and the cable 110 and comprises a buffer material. The upper buffer portion 70 is disposed between the upper groove portion 41 and the cable 110 and includes a buffer material.

The lower cushioning portion 60 and the upper cushioning portion 70 can suppress the breakage of the cable 110 due to the direct contact between the cable 110 and the lower fixing portion 30 and the upper fixing portion 40. The lower cushioning portion 60 and the upper cushioning portion 70 may have a thickness enough to prevent direct contact with metal objects and may be formed to have a curvature corresponding to the lower groove portion 31 and the upper groove portion 41 .

The lower protrusion 65 formed in the lower cushioning portion 60 is inserted into the lower insertion portion 35 formed in the lower groove portion 31. For example, the lower projection 65 protrudes downward from the lower cushioning portion 60, and the lower insertion portion 35 may be recessed into the lower groove portion 31. The lower protrusions 65 and the lower insertion portions 35 may be formed to have a length in the width direction of the cable 110 and may be spaced apart from each other in the longitudinal direction of the cable 110. By inserting the lower projection 65 into the lower insertion portion 35, the position of the lower cushioning portion 60 can be guided, and the lower cushioning portion 60 can be prevented from departing.

The upper protrusion 75 formed in the upper cushioning portion 70 is inserted into the upper insertion portion 45 formed in the upper groove portion 41. The upper protrusion 75 protrudes upward from the upper cushioning portion 70 and the upper inserting portion 45 can be formed to be recessed into the upper groove portion 41. [ The upper projection 75 and the upper insertion portion 45 are formed to have a length in the width direction of the cable 110 and a plurality of the upper projection 75 and the upper insertion portion 45 can be disposed in the longitudinal direction of the cable 110. By inserting the upper projection 75 into the upper insertion portion 45, the position of the upper buffer portion 70 can be guided and the upper buffer portion 70 can be prevented from departing.

A process of grasping a cable by the underground transmission line laying apparatus according to an embodiment of the present invention having the above-described structure will now be described.

A connection part 130 connecting the cable 110 and a support part 10 on the inner wall of the corresponding manhole 100 between the channel part 120 communicating with the manhole 100 by guiding the cable 110 in the ground Install it.

A plurality of lower fixing portions 30 are disposed on the upper side of the receiving portion 10 and the cable 110 is seated on the lower groove portion 31 formed on each lower fixing portion 30. [ At this time, a lower buffer 60 may be disposed between the lower groove 31 and the cable 110, and a lower projection 65 may be inserted into the lower insertion portion 35 to insert the lower buffer 60 Can be induced.

The upper fixing part 40 is arranged to face each lower fixing part 30 so as to cover the upper side of the cable 110 in a state where the cable 110 is seated on the lower fixing part 30. [ At this time, the upper cushioning portion 70 may be disposed between the upper groove portion 41 and the cable 110, and the upper projection 75 may be inserted into the upper insertion portion 45 to insert the upper cushioning portion 70 Can be induced.

The fixing bolts 51 penetrate through the upper engaging hole portion 42 and the lower engaging hole portion 32 and the receiving hole portion 12 in a state where the lower fixing portion 30 and the upper fixing portion 40 face each other, And the fixing nut 52 is fastened to the lower end portion of the fixing bolt 51 at the lower portion of the receiving portion 10.

At this time, a plurality of fixing bolts 51 and fixing nuts 52 are used, the tightening torque of the fixing bolts 51 is not to exceed 300 kgcm, and the interval between the fixing portions 20 is 500 mm or less .

The lower groove 31 and the upper groove 41 are designed to have a groove shape so that the cable 110 can be inserted therein and the groove is designed to have a narrow width in the longitudinal direction of the cable 110, The gripping force with respect to the cable 110 is increased at the point where the width of the upper groove portion 41 is narrow, and the axial force of the cable 110 can be suppressed.

154kV XLPE 2500mm2 (aluminum conductor) cable, which generates a large amount of heat expansion according to the linear expansion coefficient of the two types of cables according to the present invention, which is larger than the 154kV XLPE 2000mm2 (copper conductor) cable by about 30% In the case of applying the manhole underground transmission line laying apparatus 1 proposed in the present invention, the axial force reduction characteristics according to the cable displacement in the pipeline will be examined.

Generally, ignoring the cable buckling (or snake) phenomenon in the pipeline and the counterforce of the manhole offset when the cable is laid on the pipeline, the axial force P appearing in the manhole due to the rise of the cable temperature is expressed by Equation The tensile stress of the cable due to thermal expansion and contraction becomes a force reduced by the cable frictional force in the pipeline.

E: Young's modulus of elasticity [kg / mm 2], A: Conductor cross section [mm 2], ?? ?? : Coefficient of linear expansion [1 / C]

ΔT: change in conductor temperature [° C], ???? : Coefficient of friction between pipe and cable

W: Cable unit weight [kg / m], L: Cable length [m]

The tests were carried out for both the straight line + curved line of 300 [m] length and the straight line of 40 [m] length laid on the test site. The straight line + curve of 300 [m] In order to calculate the theoretical axial force of the copper conductor cable and the aluminum conductor cable at the time of construction, the cable parameter was calculated by using Equation 1, and the axial force of the copper conductor cable was 5100 [kg] and the axial force of the aluminum conductor cable was Which is about 1.8 times of the copper conductor cable, is 9091 [kg]. It can be seen that the axial force of the copper conductor cable is 1456 [kg] and the axial force of the aluminum conductor cable is 2900 [kg], which is about 2.0 times of the copper conductor cable, even in the case of 40 [m] straight construction.

On the other hand, in order to measure the thermal mechanical characteristics of the cable and the amount of displacement of the cable due to thermal expansion and contraction in the case of laying the cable in the manhole inside the non-offset (straight line construction) method, And the cable axial force at the front of the connection was measured. At this time, five fixing portions proposed by the present invention having a maximum holding force of 500 [kg] were installed at 500 [mm] intervals between the connecting portion and the duct portion.

On the other hand, in the demonstration test, considering the installation condition of the field line, etc., the cables are laid at approximately 300 [m] in the straight + curved section, and the cable thermal expansion and contraction according to the temperature change are greatest, The experimental results were simulated by simulating two cases where only the straight line section was generated. In order to measure the force applied to the front end of the connection part, the cable was installed in a non-offset manner using the fixing part proposed in the present invention and the cable conductor temperature was changed from room temperature to 90 [ The temperature was maintained at 90 [deg.] C for 1 hour and then the temperature was cooled for 16 hours. As a result of the test, the cable displacement in the pipeline is about 3.4 [mm] in the longitudinal direction and about 1.7 [mm] in the lateral direction when the cable in the pipeline is installed at about 300 [m] , And it was confirmed that the same characteristics were observed when 40 [m] was installed as a straight line section.

In this case, the cable actual axial force is about 12.4% of the theoretical value in case of straight line + curve construction of 300 [m] and about 47% of the theoretical value in case of straight line construction of 40 [m] Respectively. That is, the largest cable axial force measurement value is about 1,368 [kg], which is about 47 [%] of the theoretical value 2,900 [kg], and it is designed to absorb axial force of 1,450 [kg] considering 50 [%] , It is possible to absorb all of the actual axial force when installing the five fixed portions when estimating the holding force of the fixed portion designed by the present invention to be about 510 [kg] or 350 [kg] considering the safety factor. The offset can be installed, and the manhole size can be reduced accordingly, thereby reducing the construction cost.

The manhole ground transmission line laying apparatus 1 according to an embodiment of the present invention is capable of constructing a straight line of the cable 110, thereby reducing the size of the manhole 100.

The manhole ground transmission line laying apparatus 1 according to the embodiment of the present invention has a configuration in which the size of the lower groove 31 and the upper groove 41 is reduced so that a part thereof is formed to correspond to the diameter of the cable 110 The gripping force of the cable 110 inserted into the lower groove 31 and the upper groove 41 can be increased.

The underground transmission line laying apparatus 1 according to the embodiment of the present invention is constructed such that the lower buffering portion 60 and the upper buffering portion 70 surround the cable 110, The cable 110 can be protected by preventing direct contact between the upper portion 30 and the upper fixing portion 40.

The underground transmission line laying apparatus 1 according to the embodiment of the present invention is configured such that the lower projection 65 of the lower cushioning portion 60 is inserted into the lower insertion portion 35, The protrusions 75 are inserted into the upper insertion portion 45 so that the insertion positions of the lower cushioning portion 60 and the upper cushioning portion 70 are induced and they can be prevented from moving in the longitudinal direction of the cable 110 have.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims. I will understand. Accordingly, the true scope of protection of the present invention should be defined by the following claims.

10: pedestal portion 12: pedestal portion
20: Fixing portion 30: Lower fixing portion
31: lower groove portion 32: lower engagement hole portion
35: lower insertion portion 40: upper fixing portion
41: upper groove portion 42: upper engagement hole portion
45: upper insertion portion 50:
51: Fixing bolt 52: Fixing nut
60: lower buffer part 65: lower projection
70: upper buffering part 75: upper projection
100: Manhole 110: Cable
120: conduit part 130: connection part

Claims (6)

A pedestal portion fixed to the manhole and disposed between the connecting portion connecting the cable and the duct portion; And
And a fixing part which is fixed to the receiving part and which grips the cable which is connected to the connecting part through the pipe part,
The cable is gripped by the fixing portion and linearly constructed,
The fixed portion
A lower fixing part which is seated on the receiving part and in which a lower groove part is formed to surround a lower side of the cable;
An upper fixing part disposed above the lower fixing part and having an upper groove part to cover an upper side of the cable; And
And a fixed engaging portion that engages the upper fixed portion and the lower fixed portion and fixes the lower fixed portion to the receiving portion,
The size of the lower groove portion decreases from one end to the other end of the lower fixing portion,
The size of the upper groove portion decreases from one end to the other end of the upper fixing portion,
Wherein the narrowest portion of the lower groove portion and the upper groove portion corresponds to the diameter of the cable.
2. The apparatus of claim 1,
Wherein a plurality of the power transmission lines are disposed apart from each other.
delete delete 2. The apparatus of claim 1,
A lower buffer disposed between the lower groove and the cable and including a buffer material; And
Further comprising an upper cushioning portion disposed between the upper groove portion and the cable, the upper cushioning portion including a buffer material.
6. The method of claim 5,
The lower protrusion formed in the lower cushioning portion is inserted into the lower insertion portion formed in the lower groove portion,
Wherein the upper protrusion formed in the upper cushioning portion is inserted into the upper inserting portion formed in the upper groove portion.

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