JP4367562B2 - Sluice freezing prevention device - Google Patents

Description

  The present invention relates to a sluice freezing prevention device, and more specifically to a sluice freezing prevention device using a skin current heating method in an induction heating method.

  A sluice such as a dam in a cold region often becomes inoperable due to freezing. Specifically, the sluice facilities in the snowfall area generate ice and snow on the water surface in contact with the sluice door body of the reservoir in winter, and furthermore, the top surface of the door body, both right and left grooves, side watertight rubber plates, bottom edge bottom Ice and snow are generated on the door plate, bottom watertight rubber plate, etc., and the door body itself freezes and often cannot be opened and closed.

  Therefore, the following heat sources for preventing freezing have been used in order to prevent the sluice gate from being opened and closed even in winter.

(1) Heating by each method such as hot water circulation, hot air circulation, hot oil / antifreeze liquid circulation, etc.In each of these methods, there is a failure of the heating equipment, the risk of freezing of the heating pipe, a decrease in the ventilation capacity due to the accumulation of water in the ventilation path, There are various disadvantages such as the occurrence of oil spill pollution to the river due to the damage of the oil system.

(2) Electric heating Electric heating includes resistance heating, arc heating, induction heating, infrared heating, beam heating, and other methods.

  Among these, the sluice freezing prevention device using the skin current heating tube has various advantages as compared with the heating method using hot water, hot air, hot oil, or the antifreeze liquid circulation method. 1 and 2 are diagrams each showing a skin current heating tube, FIG. 1 shows a series skin current heating tube, and FIG. 2 shows an induction skin current heating tube. In these, reference numerals 1 and 1 'are ferromagnetic heat-generating steel pipes, 2 is an insulated wire or cable relatively freely passed through the steel pipe, 3 is an AC power source, usually a commercial frequency, and 4, 4' Etc. are connecting wires.

  In the case of FIG. 1, one end of the AC power source 3 and the terminal 6 of the steel pipe 1, the other end of the AC power source 3 and the insulated wire 2, and the terminal 5 of the steel tube 1 and the opposite terminal of the power source 3 of the wire 2 are connected. The insulated wire 2 and the steel pipe 1 are connected to the AC power source 3 in series.

  In the case of FIG. 2, both ends of the insulated wire 2 and both ends of the power source 3 are connected by connecting wires 4 and 4 ', respectively, and the two steel pipes 1 and 1' are electrically connected by short-circuit pieces 7 and 8 at both ends. The secondary circuit is connected to the primary circuit formed by the power source 3, the connecting wires 4, 4 ′ and the wire 2.

  In FIG. 2, the thickness of the steel pipes 1, 1 ', etc. is t (cm), the length is l (cm), the inner diameter of the steel pipe is D (cm), and the skin showing the range in which the alternating current flows through the inner skin of the steel pipe. Assuming that the thickness is S (cm), the alternating current i hardly flows to the outer peripheral portion of the steel pipes 1 and 1 ′ under conditions such as t> 2S, l >> D, D >> S. Therefore, even if metal contact is made with the outer peripheral surface of the steel pipe, no arc is generated and no danger is given to humans or animals. 1 and 2, the single-phase AC circuit has been described, but a multi-phase AC circuit can be configured by combining these heat generating tubes.

Such a sluice freezing prevention device using a skin current heating tube is known from the following Patent Document 1.
Japanese Examined Patent Publication No. S57-40293 “Electric sluice gate with freezing prevention” (Notification date: August 26, 1982) The skin current heating tube disclosed in Patent Document 1 is as follows. FIG. 8 is a schematic view of the sluice as seen from the water side. Reference numeral 15 denotes a door body, and 16 denotes a support structure on both the left and right sides of the door body 15. FIG. 9 is a cross-sectional view of the door body 15, and FIG. 10 is a schematic view of a left and right support structure portion of the door body 15.

  When the snow and snow 17, 18, 22, 23 generated in the vicinity of the door body cross-section central steel plate 11, the door body front steel plate 31 and the bottom sluice door stop plate 21 in FIG. 9 are frozen, the sluice gate is opened and closed. Similarly, when the ice and snow 29 generated near the groove forming plate 26 and the door stop plate 28 in FIG. 10 freezes, the opening and closing of the sluice is hindered.

  In order to prevent this, as shown in FIG. 11, each group 32, 33, 34 of the skin current heating tubes is applied to the door body cross-section central steel plate 11, the door body front steel plate 31 and the door body bottom sluice door stop plate 21. , 35, and 36, and the sluices 11, 31 and 21 and the bottom watertight rubber plate 20 are heated to prevent the sluice from freezing. Similarly, the groups 37 and 38 of the skin current heating tubes are attached to the groove forming plate 26 and the door plate 28 in FIG. 12, and the sluices 26 and 28 and the side watertight rubber plates 27 are heated to prevent the sluice from freezing. It is carried out.

  As a method of attachment, it is described that the heat generating rods 1 and 1 'are directly welded, a heat transfer cement or the like is used depending on the situation, and sometimes they are in close contact. The above is the disclosure of the skin current heating tube of Patent Document 1.

  The electric power required to prevent freezing varies depending on the weather conditions or the structure and local area of the sluice, but it is not so large as a few hundred watts per square meter of area requiring freezing prevention, or slightly higher. It is possible to completely eliminate defects caused by hot air, hot oil, etc., and is highly efficient. Therefore, the amount of heat is small, and automatic control is surely simple.

  Such a skin current heating tube has advantages such as excellent heating efficiency, durability and weather resistance.

  However, the skin current heating tube described in Patent Document 1 is a circular tube, and the attachment method is either direct welding, fixing with heat transfer cement, or close contact.

  As shown in FIG. 6, each group of skin current heating tubes is attached to the sluice steel plates 11, 21, 26, and divided into groups corresponding to the amount of heat generation necessary for freezing prevention. It is attached in contact with each steel plate. The mounting cross section is in line contact with the sluice steel plates 11, 21, 26, 28 because the heating tubes 1, 1 ′ have a circular tube shape. For this reason, the conduction path of the heat generating tube 1 and 1 'heat generation is extremely limited, and heat is not effectively transferred. In order to improve the heat transfer to the steel plate, it is conceivable to use the heat transfer cement 12 or the like. However, even if the heat transfer cement 12 is filled to improve heat conduction to some extent, heat transfer is not sufficient.

  Furthermore, the work for filling and applying the heat transfer cement 12 is complicated and there is a problem in workability.

  Furthermore, as a closed circuit based on the heat generation principle of the skin current heating tube, it is necessary to install the short-circuit pieces 7 and 8 (see FIG. 2), and since it is welded to the heating tube mutual and sluice door plate steel at a predetermined location, There was also a problem with these workability.

  Accordingly, an object of the present invention is to provide a novel sluice-freezing prevention device with further improved heat transfer efficiency.

  In view of the above-described object, the present invention provides a freeze prevention device for a sluice gate according to the present invention including a heat generating steel plate that is fixed to a heated member in a freeze prevention range of a sluice facility, and the heat generation steel plates are arranged side by side. The heat generating steel sheet has a plurality of heat generating steel sheets, and each of the heat generating steel sheets is made of a generally rectangular ferromagnetic steel sheet. In addition, an AC power source is connected to the insulated wire, and the heat-generating steel plate alone is fixed in surface contact with a member to be heated in the anti-freezing range.

  Further, in the sluice freeze prevention device, the freeze prevention range member of the sluice facility is a relatively moving member that may freeze due to snow and snow, and the door body central steel plate, door body front steel plate, It may be one selected from the group consisting of a door body bottom water gate door plate, a bottom water tight rubber, a groove forming plate, and a door plate side water tight rubber plate.

  Further, in the sluice freezing prevention apparatus, the heat generating steel plate may include a plurality of the heat generating steel plates arranged in the length direction, the width direction, and the thickness direction.

  Furthermore, in the sluice freezing prevention apparatus, the heating steel plate may be connected to the AC power source for each predetermined number of heating steel plates.

  Further, in the sluice freezing prevention apparatus, the single exothermic steel plate has a generally rectangular shape, and an outer flat surface portion of the exothermic steel plate itself is in surface contact with a flat surface portion of a member in the antifreezing range of the sluice facility. And may be fixed.

  Furthermore, in the sluice freeze prevention device, when the member to be heated in the freeze prevention range of the sluice facility is not flat, the outer peripheral surface of the exothermic steel plate alone may be shaped to fit this.

  Furthermore, in the sluice freeze prevention device, the heat generating steel plate may be fixed to a heated member in a freeze prevention range of the sluice facility by welding or bolting.

  Further, in the sluice freezing prevention apparatus, the AC power source may be a single-phase AC power source or a three-phase AC power source.

  Furthermore, in the sluice freezing prevention device, the insulated wire insertion hole formed in the heat generating steel plate has one or more in the thickness direction of the steel plate corresponding to the required heat generation amount, and a plurality of holes are formed in each layer. May be.

  Further, in the sluice freezing prevention device, the heat-generating steel plate itself has the thickness of the ferromagnetic steel plate t (cm), the length 1 (cm), the inner diameter of the insulated wire insertion hole D (cm), and the alternating current. If the thickness of the skin showing the range where the current flows in the inner peripheral portion of the insertion hole is S (cm), t> 2S, l >> D, D >> S may be satisfied.

  Further, in the sluice freezing prevention apparatus, the insulated wires may be alternately folded and passed through the plurality of insulated wire insertion holes so that the directions of currents adjacent to each other are reversed.

  Further, the construction method of the sluice antifreeze device according to the present invention includes a step of fixing a plurality of exothermic steel plates to a heated member in a freeze prevention range of the sluice facility, and an insulation formed on the exothermic steel plate alone. A method for constructing a sluice freezing prevention device, including a step of passing an insulated wire through an electric wire insertion hole and a step of connecting an AC power source to both ends of the insulated wire, wherein the heating steel plate alone has the freeze prevention range. It is fixed in contact with the heated member.

  ADVANTAGE OF THE INVENTION According to this invention, the freezing prevention apparatus of the new sluice which improved heat transfer efficiency further can be provided.

  DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of a sluice freezing prevention device according to the present invention will be described in detail with reference to the accompanying drawings. In the figure, the same elements are denoted by the same reference numerals, and redundant description is omitted.

[Sluice freezing prevention device]
The anti-freezing device for a sluice according to the present embodiment uses a skin-current heating steel plate that has a hole formed in a cross section of a ferromagnetic steel plate and is configured to pass through an insulated wire. This skin current heating steel plate is based on the same heat generation principle as the induction skin current heating tube of FIG.

  FIG. 3 is a diagram for explaining the principle of the skin current heating steel plate. In this skin current heating steel plate, a plurality of insulated wire insertion holes 10 are formed at predetermined intervals in the cross section of the ferromagnetic heating steel plate 9, and the insulated wires 2 are passed through the insertion holes 10. A commercial frequency AC power supply 3 is connected. As described above, when a voltage is applied by the AC power supply 3, the secondary current concentrates and flows only in the inner peripheral portion of the hole 10, and the steel plate 9 generates heat due to Joule heat.

The secondary current i _{2 on the} inner surfaces of the steel pipes 1, 1 ′ explained in FIG. 2 flows as a circulating current with the short-circuit pieces 7, 8 being closed. On the other hand, in the heat generating steel plate 9 of FIG. 3, the entire steel plate becomes a steel pipe and a short-circuit piece, the secondary current i ₂ flows through the inner surface (inner peripheral portion) drilled in the cross section of the steel plate, and the circulating current (vortex) flows through the steel plate 9. Current) flows. The heat generation action of the skin current heating steel plate is the same as that of the induction skin current heating pipes 1 and 1 'shown in FIG. In terms of structure, in FIG. 2, the heating element is a steel pipe 1, 1 ', and in FIG. 3, the heating element is a steel plate 9, which are different from each other.

  The depth length of the ferromagnetic heat-generating steel plate 9 in FIG. 3 is preferably a short length that can be drilled. Further, in FIG. 3, two perforations per layer (in the plate thickness direction) are formed on the cross section of the steel plate. However, the number of layers and the number of perforations depend on the amount of heat generated to prevent freezing. Individual drilling is possible. In the following description, one heat generating steel sheet 9 is also referred to as “a heat generating steel sheet alone”.

  FIG. 3 shows a case where the AC power supply 3 is a single-phase AC, and the insulated wire insertion hole 10 has a multiple of 2 (even numbers). When three-phase alternating current is used as the alternating current power source, an odd number of holes are formed. In order to simplify the description, it should be understood that the case where single-phase alternating current is used will be described below.

  As shown in FIG. 4, the exothermic steel plate is formed by connecting a plurality of exothermic steel plates 9, 9 ′, 9 ″ corresponding to the range where the sluice needs to be prevented from freezing. , 9 ′, 9 ″ generate heat for each unit. Here, the exothermic steel plate of FIG. 4 is an example comprised of four perforations per layer (in the plate thickness direction) with respect to the cross section of the steel plate.

  The exothermic steel plate shown in FIG. 5 is an example in which eight holes are formed in two layers with respect to the cross section of the steel plate (in the thickness direction). Thus, depending on the required heat generation amount, it is possible to drill the insulated wire insertion holes 10 composed of two or more layers on the cross-section of the steel sheet, and the number of the insulated wire insertion holes 10 in each layer is also the same. It can be arbitrarily determined.

  4 and 5 show an example in which a plurality of heat generating steel plates 9, 9 ', 9' 'are connected in the length direction. However, the heat generating steel plates 9, 9', A plurality of 9 ″ may be connected in the width method. Further, a plurality of exothermic steel plates 9, 9 ′, 9 ″ may be stacked and connected in the thickness direction to form a multiplexed exothermic steel plate.

  Further, the AC power source 3 does not have to be one for each of the heat generating steel plates 9, 9 ′, 9 ″ connected in a plurality. The AC power source 3 is provided for every certain number of heat generating steel plates. As a result, even if a defect such as disconnection occurs at one location, the failure of the freeze prevention device is limited to a part, and the failure of the entire freeze prevention device can be avoided. In order to do so, it is only necessary to repair and replace a certain number of heat generating steel plates.

  As shown in Fig. 7, the skin current heating steel plates 9 to 9 "described with reference to Figs. 3 to 5 are fixed to the sluice steel plates 11, 21, 26 and 28 which are heated members. The heating member is a relatively moving member that may freeze due to ice and snow, that is, a moving member and a stationary member adjacent to the moving member. The skin current heating steel plates 9 to 9 ″ are in close contact with the sluice steel plates 11, 21, 26, and 28, so that the heat conduction from the skin current heating steel plates to the sluice steel plates and the like. Excellent in heat efficiency. As described with reference to FIGS. 3 to 5, by making the heating surface a steel plate-like plane, it is possible to make a surface contact with the plane of the sluice steel plates 11, 21, 26, 28 and to have good heat conduction I have to. In addition, when the shape of the sluice steel plates 11, 21, 26, 28 is not flat, by adopting the skin current heating steel plates 9 to 9 ″ having a shape suitable for the shape, they can be brought into surface contact with each other, and the same effect can be obtained. Can also be obtained.

[Example of installation on a sluice]
FIGS. 13 and 14 are views of the skin current heating steel plates installed at the freeze-prevention portions of the sluice, and enlarged views are shown in FIGS. 15, 16, 17 and 18, respectively.

  Each group of the skin current heating steel plates so that the back surface of the door body cross section central steel plate 11 and the door body front steel plate 31 in FIG. 39, 40, 41 are attached. Each group 39, 40, 41 of the skin current heating steel plate can be attached to the outer surface of the door body cross-section central steel plate 11 and the door body front steel plate 31. With respect to obstacles (driftwood and others) from upstream of the pond water 24, the skin current heating steel plate has sufficient mechanical strength and has an advantage that a further ice melting effect can be obtained because the heating surface is directly on the outer surface.

  As shown in FIG. 15, each group 39, 40, 41 of the skin current heating steel plates is subdivided into shapes along the curved surfaces of the door body cross-section central steel plate 11 and the door body front steel plate 31, and welded 13 Alternatively, it is installed with a fixing bolt 14 or the like (see FIG. 7).

  As shown in FIG. 17, there is a bottom watertight rubber plate 20 at the bottom of the door body cross-section central steel plate 11 and door body front steel plate 31, and the skin on the back of the water gate door plate 21 to prevent freezing of this watertight rubber. A current heating steel plate 43 is attached in close contact. Further, the skin current heating steel plate 42 is attached together with the pressing plate of the bottom watertight rubber plate 20, and the bottom watertight rubber plate 20 is heated by heat transfer of the skin current heating steel plate 42 to prevent freezing.

  As shown in FIG. 14, each group 44, 45, 46, 47, 48, 49 of skin current heating steel plates is attached to prevent freezing near the roller 25 and the side watertight rubber plate 27 of the door guide groove 30 of the sluice. It is done.

  As shown in FIGS. 16 and 18, the skin current heating steel plates 44, 45, 46 are attached to the outer surface of the groove forming plate 26, and can melt ice and snow by directly heating the skin current heating steel plates. The skin current heating steel plate 47 heats the watertight rubber plate 27 together with the pressing plate of the side watertight rubber plate 27. The skin current heating steel plates 48 and 49 are both attached to the back side of the groove forming plates 26 and 28.

  The number of each group 44, 45, 46, 47, 48, 49 of any of these skin current heating steel plates is determined by the range necessary for freezing prevention, and the insulated wire insertion hole 10 is drilled in the cross section of each group of hot steel plates. The number of layers, the number of holes, etc. are determined according to the required heat generation amount.

[Advantages and effects of the embodiment]
The freeze prevention device for a sluice according to this embodiment has the following advantages and advantages.

  (1) A hole 10 is drilled in the cross section of the ferromagnetic heat generating steel plate 9 shown in FIG. 3, and the steel plate 9 is uniformly heated by passing an electric current i 1 from the AC power source 3 through the insulated wire 2. Since the steel plate 9 is made of a material having good thermal conductivity, the temperature of the steel plate is uniform throughout and there is no temperature difference.

  (2) By making the heat generating surface of the heat generating steel plate flat, it comes into surface contact with the smooth surface of the sluice steel plate 11, 21, 26, 28 on the frozen surface as shown in FIG. Thermal efficiency can be improved.

  (3) For the range where freeze prevention is necessary, it is sufficient to prepare the required number of relatively short and long ferromagnetic heat-generating steel plates, and to the range of any size (length, width, etc.) of the sluice. An anti-freezing device can be configured. A desired number of ferromagnetic exothermic steel sheets can be prepared in the length direction, width direction, and thickness direction to constitute an antifreezing device.

  (4) For the part where the sluice steel plate on the frozen surface is not flat, it is possible to make a surface contact between them by preparing a single exothermic steel plate having a shape suitable for the shape.

  (5) A single ferromagnetic heat-generating steel plate can be provided with two or more layers of insulated wire insertion holes 10 in the cross section of the steel plate, and the number of insulated wire insertion holes in each layer can be arbitrarily set. Can be determined.

  (6) By preparing an AC power supply for a certain number of ferromagnetic exothermic steel plates, it is possible to prevent a failure occurring at one location from reaching the entire freeze prevention device. In this case, repair and replacement may be performed in units of defects, and maintenance work can be performed efficiently.

  (7) The workability (see FIG. 6) of applying the heat transfer cement 12 for mounting the conventional heat generating steel pipes 1, 1 'and the sluice steel sheets 11, 21, 26, 28 is lost.

  (8) The short circuit piece (see FIG. 2) as a closed circuit based on the heat generation principle of the skin current heat generating tube eliminates the need for welding work of the short circuit piece because the heat-generating steel plate performs its function.

  (9) Since it is a heat-generating steel plate, the mechanical strength of the installation location is also increased.

  (10) The anti-freezing device can also be installed at the driftwood contact area on the upper upstream side of the gate body.

[Alternative examples]
As mentioned above, although embodiment of the freeze prevention apparatus of the sluice concerning this invention was described, these are illustrations and do not limit this invention. Additions, changes, deletions, changes, improvements, and the like that can be easily made by those skilled in the art to the present embodiment are included in the present invention. The technical scope of the present invention is defined by the description of the appended claims.

FIG. 1 is a diagram for explaining the basic principle of a conventional series skin current heating tube. FIG. 2 is a diagram for explaining the principle of a conventional induction skin current heating tube. FIG. 3 is a view for explaining the principle of the skin current heating steel plate of the present embodiment. FIG. 4 is a view for explaining the connection structure of the skin current heating steel plates alone according to this embodiment. FIG. 5 is a view for explaining a connecting structure of other skin current heating steel plates alone according to this embodiment. FIG. 6 is a diagram for explaining a method of attaching a conventional induction skin current heating tube to a sluice door plate. FIG. 7 is a diagram for explaining a method of attaching the skin current heating steel plate of the present embodiment to the sluice door plate. FIG. 8 is a front view of the sluice gate. FIG. 9 is a longitudinal side view showing a frozen state of the sluice door body portion due to ice and snow. FIG. 10 is a cross-sectional view showing a frozen state of the sluice door body guide groove due to ice and snow. FIG. 11 is a longitudinal side view of a sluice door body portion provided with a freeze prevention device using a conventional induction skin current heating tube. FIG. 12 is a cross-sectional view of a sluice door body induction groove portion provided with a freeze prevention device using a conventional induction skin current heating tube. FIG. 13 is a longitudinal side view of a sluice door body portion subjected to the freeze prevention device according to the present embodiment. FIG. 14 is a cross-sectional view of a sluice door body guiding groove portion provided with the freeze prevention device according to the present embodiment. FIG. 15 is an enlarged vertical side view of the front upper part of the sluice door body to which the anti-freezing device according to the present embodiment is applied. FIG. 16 is an enlarged cross-sectional view of a sluice door body guiding groove portion provided with the freeze prevention device according to the present embodiment. FIG. 17 is an enlarged vertical side view of the bottom of the sluice door body to which the freeze prevention device according to the present embodiment is applied. FIG. 18 is an enlarged cross-sectional view of a sluice door body guiding groove portion provided with the freeze prevention device according to the present embodiment.

Explanation of symbols

1, 1 ': Heat generation tube having ferromagnetism, 2: Insulated wire, 3: AC power supply, 4, 4': Connection wire, 5, 6: Terminal, 7, 8: Short-circuiting piece, 9, 9 ', 9 " : Ferrous heat generating steel plate, 10: Insulated wire insertion hole, 11: Central steel plate of door section, 12: Heat transfer cement, 13: Welding, 14: Fixing bolt, 15: Door body, 16: Door body Support structure on both sides, 17, 18: Ice / snow, 19: Gate winding rope, 20: Bottom watertight rubber plate, 21: Sluice door plate, 22, 23: Ice / snow, 24: Pond water, 25: Roller, 26: Groove formation plate 27: Side watertight rubber plate, 28: Door plate, 29: Ice and snow, 30: Door body guide groove, 31, 32: Ventilation path, 33: Door body front steel plate, 32, 33, 34, 35, 36 , 37, 38: each group of induction skin current heating tubes, 39, 40, 41, 44, 45, 46: skin current Each group of external attachment of thermal steel plate (single layer hole), 43, 48, 49: Each group of concrete side mounting of skin current heating steel plate (single layer hole), 42, 47: Outside of skin current heating steel plate (multilayer hole) Each group of mounting,
t ₁ : Thickness (cm) of heat-generating steel plate (single-layer hole drilling), t ₂ : Thickness (cm) of heat-generating steel plate (between multiple-layer holes drilled), i ₁ : Power source side primary current (A) I ₂ : Steel pipe side secondary current (A),

Claims (12)

It has a heat generating steel plate that adheres to the heated member in the freeze prevention range of the sluice gate equipment
The exothermic steel plate has a plurality of exothermic steel plates arranged side by side,
The heat-generating steel plate itself is generally composed of a rectangular-shaped ferromagnetic steel plate, and an insulated wire insertion hole is formed inside the ferromagnetic steel plate, the insulated wire is passed through the insertion hole, and an AC power source is connected to the insulated wire. Configuration
The sluice freezing prevention device, wherein the exothermic steel plate is fixed in surface contact with a heated member in the freezing prevention range. In the sluice freezing prevention device according to claim 1,
The member to be heated in the anti-freezing range of the sluice gate is a relatively moving member that may freeze due to snow and snow, and the door body center plate steel plate, the door body front plate steel plate, the door body bottom sluice door plate, The sluice freezing prevention device, which is one selected from the group consisting of a bottom watertight rubber, a groove forming plate, and a door plate side watertight rubber plate. In the sluice freezing prevention device according to claim 1,
The heat generating steel plate is a sluice freezing prevention device in which a plurality of the heat generating steel plates are arranged in a necessary number in the length direction, width direction and thickness direction. In the sluice freezing prevention device according to claim 1,
The sluice freezing prevention device, wherein the heat generating steel plate is connected to the AC power source for each predetermined number of heat generating steel plates. In the sluice freezing prevention device according to claim 1,
The exothermic steel plate has a generally rectangular shape, and the outer plane portion of the exothermic steel plate is fixed in surface contact with the plane portion of the antifreeze range member of the sluice facility, and the sluice freeze prevention apparatus. In the sluice freezing prevention device according to claim 1,
When the member to be heated in the freeze prevention range of the sluice gate is not flat, the sluice freeze prevention device is configured such that the outer peripheral surface of the heat-generating steel plate is adapted to this. In the sluice freezing prevention device according to claim 1,
The sluice freezing prevention device, wherein the heat generating steel plate is fixed to a member to be heated in a freezing prevention range of the sluice facility by welding or bolting. In the sluice freezing prevention device according to claim 1,
The AC power source is a sluice freezing prevention device, which is a single-phase AC power source or a three-phase AC power source. In the sluice freezing prevention device according to claim 1,
The sluice freezing prevention device, wherein the insulated wire insertion hole formed in the heat generating steel plate has one or more layers in the thickness direction of the steel plate corresponding to the required heat generation amount, and a plurality of holes are formed in each layer. In the sluice freezing prevention device according to claim 1,
In the heat generating steel plate alone, the thickness of the ferromagnetic steel plate is t (cm), the length is l (cm), the inner diameter of the insulated wire insertion hole is D (cm), and the alternating current flows through the inner peripheral portion of the insertion hole. A sluice freezing prevention device satisfying t> 2S, l >> D, D >> S, where S (cm) is the thickness of the epidermis showing the range. In the sluice freezing prevention device according to claim 1,
A sluice freezing prevention device in which the insulated wires are alternately folded and passed through the plurality of insulated wire insertion holes so that the directions of currents adjacent to each other are reversed. A step of arranging a plurality of heat-generating steel plates in a fixed manner on a member to be heated in a freeze prevention range of a sluice facility,
Passing the insulated wire through the insulated wire insertion hole formed in the exothermic steel plate; and
Including a step of connecting an AC power supply to both ends of the insulated wire, and a method of constructing a sluice freezing prevention device,
The construction method of the sluice anti-freezing device, wherein the exothermic steel plate is fixed in surface contact with the heated member in the anti-freezing range.

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