JPS586107A - Tank for oil-filled electric apparatus - Google Patents

Abstract

PURPOSE:To contrive to absorb the deformation amount by a rise in pressure and to eliminate dead space as well by improving the structure of tank corner sections in an oil-filled tank composing a body section by using corrugated heat sinks having many fin shaped overhanging sections. CONSTITUTION:The body section of a tank for oil-filled electric apparatus is formed between each side of an upper frame body 12 and lower frame body 13 by spreading corrugated heat sinks 20, 21 having many fin-shaped overhanging sections blocked the upper and lower end sections. The corrugated heat sink 20 has breadth which is equal to the length adding the length l of upper and lower joint plate sections 14, 15 to the length of the long sides of the upper and lower frame bodies 12, 13. The upper and lowe ends of a central section 20a and those of right and left extention sections 20b are oil tightly joined to the long sides of the upper and lower frame bodies 12, 13 and the sides of the upper and lower joint plate sections 14, 15 respectively. The corrugate heat sink 21 has breadth which is equal to the length of the short sides of the upper and lower frame bodies 12, 13 and the upper and lower ends are joined in oil-tight manner to the short sides of the upper and lower frame bodies 12, 13.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in an oil-immersed electrical appliance header whose body portion is constructed using a corrugated heat sink with high cooling effect, which is made by continuously bending a thin steel plate.

FIG. 1 is a front view of a conventional oil-immersed transformer using this type of tank, FIG. 2 is a cross-sectional view of the tank body, and FIG. 5 is an enlarged cross-sectional view of the corner of the tank. Evening/return 1 shown in these figures
The upper frame body 5 is provided with seven lunges for attaching the tank cover 4, and the lower frame body 6 is attached with a tank bottom plate.
A corrugated heat dissipating plate 2 having a large number of fin-like protrusions 3 whose upper and lower ends are closed by welding is stretched between each side of the body to form a body, and each corner 7 of the body is a corrugated heat dissipating plate. It is constructed by bending the plate 2 at right angles or by joining the ends of the corrugated heat sink 2 by welding.

Tanks using this type of corrugated heat sink are mainly used in medium to small-sized oil-immersed transformers, and are useful for making transformers smaller and lighter. However, when applied to larger capacity transformers, etc.
For the reasons described below, there were restrictions on the height and number of fin-like protruding parts of the corrugated heat sink, and there was a limit to miniaturization and weight reduction.

In other words, this type of tank has insulating oil sealed inside to cool and insulate the main body of the electrical equipment, and depending on the application, it must be sealed with a space for pressure adjustment. The static pressure from the insulating oil head and the dynamic pressure from the volumetric expansion of the internal air as the temperature rises (.

In FIG. 3, the state in which the fin-like protruding portions of the corrugated heat sink in a conventional tank are deformed due to these internal pressures is shown by two-dot chain lines. This deformation appears symmetrically as δ1 around point A in the abdomens 3a on opposite sides of the adjacent fin-like overhangs 6, and the amount of deformation is relatively small. However, in the abdomen 3b facing the corner 7 of the fin-like overhang 6 located near the corner 7, a larger deformation than δ1 occurs, such as δ2.For example, when the plate thickness t=1. 2mm + height of overhang (wave height) h = 515 mm r width of overhang (
Wave width) b = 10.4mm, interval (pitch) of overhanging parts
11 = 37.5 mm + distance L2 from the corner 7 to the nearest overhang = 50 mm, length t5 = 1524 mm of the upper and lower ends of the overhang.
．． When an internal pressure of 1 kg/cm2 is applied, δ is 10 mm
A deformation of r δ2 = 20 mm was observed. The deformation of this fin-like overhang increases as the internal pressure increases, and eventually exceeds the elastic limit of the material and causes permanent deformation. Therefore, such δ1. In tank structures in which the amount of deformation of δ2 is different, the allowable internal pressure, etc. must be determined based on the value of δ2.

In this way, the amount of deformation of the fin-like overhang 3 near the corner is δ
The reason why 2>δ1 can be explained as follows. As shown in FIG. 4, when an internal pressure of p per unit surface collapse is applied to each part of the corrugated heat sink 2, the abdomen 3 of the fin-like overhang 3
a, 3b, M = p - a (a: moment of force acting on the abdomen 3a of the opposing side is force M against the abdomen 5a of the other side)
As a result, the amount of deformation δ1 generated in the opposing abdomens 6a is symmetrical and relatively small, but the surface on the corner 7 side of the fin-like overhang 6 near the corner 7 is Abdomen 3. Since there is no force acting from the opposing abdomen 6a as described above, and the force opposing M is only the force N applied to the pressure receiving surface of the corrugated heat sink from the abdomen 5b to the corner 7, M
)N, and as a result, it is thought that δ2>δ1. This 1@ direction is more pronounced as the ratio of the height h to the width of the overhang increases. Distance t2 from corner 7 to the nearest overhang
If you increase it to the same extent as the height h of the overhang, δ2kiδ1
However, in order to do so, the number of 60 overhanging parts must be reduced and the heat dissipation area must be sacrificed.

As described above, in oil-filled electrical equipment tanks that use conventional corrugated heat sinks, there are restrictions on the height and number of fin-like protruding parts of the corrugated heat sinks, so there is a loss of heat generated compared to the size of the contents. In order to secure the required cooling area, the length t3 of the fin-like overhang is lengthened, and the cooling If necessary, the tank body dimensions x, y shown in Figure 2.
The mounting space for the corrugated heat sink must be increased by increasing the size of the corrugated heat sink, and as a result, the size and weight of the tank increase, making economical design difficult.

As a countermeasure for this problem, the present inventors installed joint plates 8, which are made in the same shape and size as the fin-like protruding parts 6 of the corrugated heat sink 2, at each corner of the tank body, as shown in FIG. extensions 9a, 9., which are arranged symmetrically with respect to the two sides of the joint plate 8 and open at right angles. with the corrugated heat sink 2 and the welded parts 10a and 1, respectively.
I previously proposed joining with 0b (Patent application 1984-21)
No. 797). According to this configuration, when internal pressure is applied to the tank, the fins as shown in FIG. Deformation amount δ1 of the shaped overhang. It is possible to create a tank structure that is balanced in terms of strength by eliminating the unbalance of δ2, and the joint plate 8 acts as a heat dissipation plate, increasing the heat dissipation area. It was not sufficient in terms of effective utilization.

In view of the above points, it is an object of the present invention to provide a tank for oil-filled electrical equipment that is balanced in terms of strength, has a small dead space, and can be made smaller and lighter.

Embodiments of the present invention shown in FIGS. 6 to 12 will be described below.

(as shown in detail in FIG. 11), the tank 1 according to the invention
10 framework includes an upper frame 12, a lower frame 13, and upper and lower joint plate parts i4.15. It consists of a support column 16 and a base member 17.

The upper frame 12 is formed by combining L-shaped members into a frame shape consisting of long sides and short sides to form a flange 18 that serves as a mounting seat for the tank cover, and has a flange 18 at each corner extending parallel to the long side. The upper joint plate 14 is formed by an extension of the long side profile.

The lower frame body 15 is formed by bending a steel plate into a frame shape consisting of long sides and short sides, and a tank bottom plate 19 is integrally attached to the bottom frame body 15. At each corner, there is a frame having the same thickness as the upper joint plate part 14. The lower joint plate part 1 is made by joining the plates of 1 by welding and extending parallel to the long side.
5. This lower frame body 13 is placed on a base member 17 made by combining U-shaped steel.

The long side of the cross-sectional support column 16 is connected to the upper and lower frames 12.1.
6, and the short side is located parallel to the short side of the upper and lower frames 12.6.
Upper and lower joint plates @1 so that they are located on the extension line of the long side of 13
a-', 15 by welding, and its lower end is fixed onto the base member 17 by welding. The cross-sectional shape of the pillar 16 is not limited to the L-shape, and can also be formed by the corrugated heat sink 2 described later.
It is sufficient if it has two side surfaces that are overlapped and joined to the side portions 24 and 25 of 0.21 mm.

Corrugated heat sinks 20.
21 to form the tank body.

The corrugated heat dissipation plate 20.21 has a large number of fin-like protruding parts 22.23 formed by bending a thin steel plate into a corrugated shape, closing the upper and lower ends of the corrugated parts, and sealing them by welding. Side parts 24.25 are formed which are bent approximately parallel to the shaped projections 22.23.

As shown in Figures 6 to 8, the corrugated heat sinks 20 on two of the four sides are made by adding the length t of the upper and lower joint plate parts 14.15 to the length of the long side of the upper and lower frames 12.16. It has a width equal to the length X', the upper and lower ends of the central part 20a overlap the long sides of the upper and lower frames 12.13, and the upper and lower ends of the left and right extension parts 20 are placed on the upper and lower joint plate parts 14.15Ω-side. Welded together in an oil-tight manner,
In addition, the left and right side portions 24 overlap the long side surfaces of the column 16,
The corrugated heat sinks 21 on the other two sides have a width equal to the length y' of the short side of the upper and lower frames 12. The upper and lower frames 12
．． The three edges of the left and right sides 25 are connected to the other side of the upper and lower joint plate parts 14 and 15, and the struts are formed on the same plane as the upper and lower joint plate parts 14. It is overlapped with the side surface of the short side of 16 and is oil-tightly joined by welding.

FIG. 9 is a sectional view of the tank body configured in this way taken along the line A-A in FIG. 7, and FIG. This is a cross-sectional view taken along a line. In the figure, 26a and 26b show the welded parts of the corrugated heat sink 20.21 and the upper and lower joint parts 14.15, and 26c and 26d show the welded parts of the corrugated heat sink 20.21 and the support column 16. There is.

According to the above configuration as seen in FIGS. 9 and 10,
At each corner of the tank 11 there are upper and lower joint plate parts 14, 15 and struts 1.
Surrounded on three sides by 6 1. Extension part 2 of corrugated heat sink 20
0b and the side portions 25 of the corrugated heat sink 21 form an oil passage 27 whose both sides are covered, and the oil in the tank passes through this oil passage 27 to the fin formed on the extension portion 20b of the corrugated heat sink 20. Inside the shaped overhang portion 22 and the side portion 24 of the corrugated heat sink 20
It flows into the gap between the and support column 16 as shown by the arrow in FIG. Therefore, with the same external dimensions as the conventional tank shown in FIGS. 1 to 3, the heat radiation area increases by an amount corresponding to the extension part 20b of the corrugated heat sink 20, and the tank corner that the conventional tank had The dead space in the area can be used to the maximum extent as a heat dissipation surface.

In addition, when this tank 11 receives internal pressure, a force corresponding to M shown in FIG. However, due to the moment of force, the abdomens 22b, 23b of the fin-like projections 22.23 facing the side parts 24.25
KMKThe opposing force acts on the abdomen 22 of the fin-like protrusion 22.25 which also faces the lateral side 24.25.
b, 23b acts against 'MK. As a result, a nearly symmetrical deformation (bulge) occurs in the abdomen where the fin-like protrusion 22.25 and the side parts 24, 25 face each other, and the deformation The amount δ2 is the abdomen 22a where the fin-like overhangs face each other,
The amount of deformation δ1 occurring in the portion 23a is approximately the same (δ2 x δ1), which is significantly smaller than that in the case where the side portions 24 and 25 are not provided. With this K, a tank with balanced strength without the unbalanced deformation amount as in the past can be obtained, and the strength restrictions on the height and number of fin-shaped overhangs are reduced, making it possible to increase the heat dissipation area. It becomes possible to increase the size.

Furthermore, according to the above structure, since the highly rigid support column 1'6 is provided on the outermost side of the tank, the support column 16 is provided with a hanging ear part 28 and a pull hole 29 for pulling the roller, and the base member By providing the jack receiving part 50 under the support column fixing part 17, there is no unbalanced force applied to the corrugated heat sink of the tank body when equipment is lifted, rolled, or pushed up by jacks. It can prevent cracks in the welding bead that cause oil leakage.

The support column 16 extends upward from the upper frame body 12, and has a hanging ear part 28 at its upper end. By doing this, when the shackle 32 of the hanging rope 31 is hooked on the hanging ear part 28 as shown in FIG. Contact with structures is avoided.

As shown in FIG. 1, in a conventional tank in which a hanging ear part 54 is provided on the upper frame body 5, it is necessary to increase the height m of the upper frame body 5 in order to hang a rope on the hanging ear part 33. However, if the hanging ear part 28 is provided at the upper end of the support column 16 as described above, the height m of the upper frame 12 can be made smaller (an example of the dimension m is 110 mm in the past, but In the present invention, 50
As a result, the height of the tank can be lowered, and the rigidity of the upper frame body 12 can be increased, so that deformation of the upper frame body 12 due to tank internal pressure is reduced. The pressure resistance of the tank can be increased by suppressing the stress generated at the weld between the body and the corrugated heat sink.

The jack receiving part 30 is formed by cutting out a part of the ground surface of the base member 17 in order to improve workability. The following table shows an example of comparing dimensions and weights of three-phase 1000 kVA oil-immersed transformers.

As explained above, according to the present invention, the unbalance of the deformation of the corrugated heat sink due to the internal pressure of the tank is eliminated, and the constraints on the height and number of the fin-like protrusions from the viewpoint of strength are reduced. ~ As shown in Figure 3, corrugated heat sinks are placed in the dead spaces at the four corners of the conventional type of heat sink, allowing for a much larger heat dissipation area, making it suitable for use in medium to large capacity oil-filled electrical equipment. The corrugated heat sink on the heel can also be effectively used in the tank to make the equipment smaller and lighter.

[Brief explanation of the drawing]

Figure 1 is a front view of a transformer with a conventional tank using a corrugated heat sink, Figure 2 is a cross-sectional view of the body of the conventional tank,
Figure 3 is an enlarged view of its main parts, Figure 4 is an explanatory diagram of the deformation of a conventional tank due to internal pressure, and Figure 5 shows another conventional example of a tank for oil-filled electrical equipment using a corrugated heat sink. Cross-sectional views of main parts, FIGS. 6 and 7. FIG. 8 is a front view, side view, and plan view of a tank for oil-filled electrical equipment according to the invention of horizontal crosspieces. FIG. 9 is a line taken from A-A of FIG. 10 is a cross-sectional view of the main part taken along line B-B in Fig. 6 and line C-C in Fig. 9. Fig. 11 is a cross-sectional view of the main part along line B-B in Fig. 6 and line C-C in Fig. 9. a perspective view showing the part;
FIG. 12 is a diagram showing the usage state of the hanging ear part. 11...Tank 12...Upper frame 13.
・・Lower frame body 14 ・・Upper joint plate part 15 ・・
- Lower side joint plate part 16... Support column 17... Base member 20.21... Corrugated heat sink 20b... Extension portion of the wave shaped heat sink 20 22.23... Fin-like overhang portion 24. 25...Side portion 27 of the corrugated heat sink 20.21.
・・Yurado 2B・・Patent attorney representing the hanging department
Junnosuke Nakamura'IP9 map Fuku

Claims (2)

[Claims] (1) In a tank for oil-filled electrical equipment, the body of which is constructed by extending a corrugated heat sink having a number of fin-like protrusions closed at the upper and lower ends between each side of the upper frame and the lower frame. ,
Upper and lower joint plate parts extending parallel to one side of both frames from each corner of the upper frame body and the lower frame body, and a column that is joined to these joint plate parts and whose lower end is fixed on the base member. The extension part of the corrugated heat sink stretched between each side of both the frame bodies and the side part bent almost parallel to the fin-like protruding part thereof are connected to one side surface of the both joint plate parts and the side part thereof, respectively. The end edges are oil-tightly joined to one side of the support, and each of the other frames of the above-mentioned frame members is
The fin-shaped overhanging part of the corrugated heat sink stretched between the sides and the side part bent approximately parallel to #1 are overlapped on the other side of the double joint plate part and the other side of the support column, and the end A tank for oil-filled electrical equipment characterized by having its edges joined in an oil-tight manner. (2) Claim (1) characterized in that the support column extends upward from the upper frame body and has a hanging ear portion at its upper end.
Tanks for oil-filled electrical equipment as described in Section 1.