JP3600723B2 - Vacuum pump unit for insulating gas recovery - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a vacuum pump unit for recovering insulating gas for recovering insulating gas such as SF6 gas from an insulating gas sealing device such as a transformer.
[0002]
[Prior art]
SF6 (sulfur hexafluoride) gas has excellent heat resistance and electrical insulation properties and is sealed as an insulating gas in encapsulation equipment such as transformers. Need to be collected.
[0003]
The conventional SF6 gas recovery device sucks an insulating gas in a sealed device such as a transformer using a vacuum pump. As the vacuum pump, an oil rotary type vacuum pump with a large displacement or an air-cooled vacuum pump is used.
[0004]
[Problems to be solved by the invention]
However, the oil rotary type vacuum pump has a problem that SF6 gas is mixed into the oil, and the air cooling type cannot use a large capacity device because of the storage container, so that only a small displacement type can be used. In addition, there is a problem that it takes a long time to recover a gas under the atmospheric pressure.
[0005]
There is also a water-cooled vacuum pump, but this pump requires a cooling water pipe such as tap water, and there is a problem that tap water cannot be secured in some places.
[0006]
Therefore, an object of the present invention is to solve the above problems and to provide a vacuum pump unit for collecting an insulating gas that can effectively cool a vacuum pump without a cooling water source such as tap water.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, the invention of claim 1 includes a main circuit that sends an insulating gas from an inlet side to an outlet side connected to a compressor side via a vacuum pump, and a bypass circuit of the vacuum pump. In addition to the above, the gas pressure on the inlet side is detected, and when the pressure is higher than a predetermined value, the main circuit is bypassed to switch to the bypass circuit, and when the pressure is low, the flow path is switched to the vacuum pump of the main circuit, and the vacuum pump is cooled by brine. Pump cooling means, further comprising a heat exchanger provided in the vacuum pump, a brine tank, a refrigerator for cooling the liquid in the brine tank, and a heat pump for cooling the liquid in the brine tank. This is a vacuum pump unit for recovering insulating gas, comprising a brine circulating path for supplying to the exchanger.
[0011]
According to a second aspect of the present invention, a pressure regulating valve, a vacuum pump, and a cushion tank are connected between an inlet-side connection port connecting the insulating gas filling device and an outlet-side connection port connecting the compressor side. A main circuit, a bypass circuit that bypasses a vacuum pump of the main circuit, a flow path switching valve that switches gas from the inlet side to flow to one of the main circuit or the bypass circuit, and a gas pressure at the inlet side that is detected and determined. A pressure detection means for controlling a flow path switching valve for switching to a bypass circuit when the pressure is higher than the pressure, and a main circuit when the pressure is lower than the pressure; and a pump cooling means for cooling the vacuum pump with brine, further comprising a vacuum pump. a heat exchanger provided, consists of a brine tank, a refrigerator for cooling the liquid in the brine tank, a brine circulation path for supplying the cooling liquid to the heat exchanger in the brine tank, this Et which is the insulating gas recovery vacuum pump unit accommodated in the same casing.
[0012]
The invention according to claim 3, a vacuum pump on the bottom of the casing, brine tank of the cooling means, the cushion tank arranged, refrigerator pumping cooling means at the top, on the front of the casing, according to claim 2, wherein placing the control panel Is a vacuum pump unit for collecting insulating gas.
[0013]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.
[0014]
First, the circuit of the vacuum pump unit for collecting insulating gas will be described with reference to FIG.
[0015]
As shown in FIG. 2, between an inlet side connection port 12A connected to a connection hose 11A connected to the insulating gas sealing device and an outlet side connection port 12B connected to a connection hose 11B to a compressor unit (not shown). A main circuit 16 to which a brine vacuum pump 13 for cooling with brine , a cushion tank 14, and a check valve 15 are connected, and a bypass circuit in parallel with the main circuit 16 between the vacuum pump 13 and the cushion tank 14. 17 is connected.
[0016]
Flow passage switching means 18 are formed by connecting flow passage switching electromagnetic valves 18a and 18b to branches of the main circuit 16 and the bypass circuit 17, respectively. A pressure gauge 20 for detecting the pressure of the insulating gas is provided upstream of the passage switching means 18. A pressure switch 21 is provided as control means for opening and closing the flow path switching electromagnetic valves 18a and 18b to switch the bypass circuit 17 and the main circuit 16 according to the detected gas pressure.
[0017]
A safety valve 23 that opens when the main circuit 16 becomes abnormally high pressure is connected to the main circuit 16 on the upstream side of the vacuum pump 13.
[0018]
A pressure balancing solenoid valve 25 is connected in parallel with the vacuum pump 13, and is further opened in parallel with the vacuum pump 13 when the pressure of the gas sent to the vacuum pump 13 becomes a predetermined value or more, and the pressure is adjusted to bypass the gas. Valve 27 is connected.
[0019]
Pump cooling means 28 is connected to the vacuum pump 13.
[0020]
The pump cooling means 28 includes a heat exchanger 29 provided in the vacuum pump 13, a brine tank 30, a refrigerator 31 for cooling the liquid in the brine tank 30, and a heat exchanger 29 for cooling the liquid in the brine tank 30. And a brine circulation path 32 for supplying the water to the water supply line.
[0021]
The refrigerator 31 is connected to a heat exchange coil 33 provided in the brine tank 30 by a refrigerant pipe 34, and the refrigerant pipe 34 is connected to an electromagnetic on-off valve 35.
[0022]
The brine circulation path 32 connects the brine tank 30 and the heat exchanger 29, and is configured such that the brine circulation pump 32 is connected to the brine circulation path 32.
[0023]
The vacuum pump unit shown in FIG. 2 is housed in a casing 10 as shown in FIG.
[0024]
1A is a plan view, FIG. 1B is a front view, and FIG. 1C is a right side view.
[0025]
As shown in FIGS. 1A, 1B, and 1C, a vacuum pump 13, a brine tank 30, and a cushion tank 14 are provided at the bottom of the casing 10, and a refrigerator 31 is provided at the top.
[0026]
On the front surface of the casing 10, the inlet side connection port 12A and the outlet side connection port 12B described with reference to FIG.
[0027]
A control panel 40 is provided on the front surface of the casing 10. The control panel 40 has operation buttons 42 for operating / stopping and resetting, operating states of the vacuum pump 13 and the refrigerator 31, a positive pressure recovery operation for atmospheric pressure, and the like. A display lamp 44 is provided to display a negative pressure recovery operation or the like in a blinking or colored manner.
[0028]
Next, the recovery operation will be described with reference to FIG.
[0029]
When recovering insulating gas from an insulating gas sealing device such as a transformer, the connection hose 11A is connected to the sealing device, and the connection hose 11A is connected to the inlet-side connection port 12A. The outlet side connection port 12B is connected to a compression unit (not shown) by a connection hose 11B.
[0030]
Next control power is ON, the insulating gas is carried out a recovery operation flows into the main circuit 16 from the inlet-side connecting port 12A, the pressure switch the recovery operation early, due to the high gas pressure in the enclosed equipment is a control means At 21, the flow path switching electromagnetic valve 18b on the bypass circuit 17 side of the flow path switching means 18 is opened, and the flow path switching electromagnetic valve 18a on the main circuit 16 side is closed, so that the recovered gas flows to the bypass circuit 17. The normal recovery operation is performed by flowing the gas from the outlet side connection port 12B to the compressor unit side.
[0031]
Thereafter, when the gas pressure drops to a set pressure, for example, near the atmospheric pressure, the flow is switched to the main circuit 16 side by the flow path switching means 18, and the suction gas of the vacuum pump 13 sucks the insulating gas in the sealed device and compresses it. Then, it flows to the compressor unit side from the outlet side connection port 12B to perform the negative pressure recovery operation.
[0032]
The status of the positive / negative recovery operation can be confirmed by the display lamp 44 of the control panel 40 shown in FIG.
[0033]
During this recovery operation, the liquid in the brine tank 30 is cooled by the refrigerator 31, and the cooling liquid is passed through the heat exchanger 29 of the vacuum pump 13 to cool the vacuum pump 13, thereby suppressing heat generation. .
[0034]
The recovered gas sent to the compressor unit is compressed, then cooled and liquefied by the liquefaction unit, and stored in the storage tank. The recovered liquid stored in the storage tank is then heated and gasified by the vaporizing unit and returned to the sealing device.
[0035]
【The invention's effect】
In short, according to the present invention, in recovering insulating gas from an insulating gas filling device such as a transformer, a vacuum pump is provided with a heat exchanger for cooling the vacuum pump, a brine tank, and a refrigerator for cooling the coolant in the brine tank. , And by providing a brine pump cooling means comprising a brine circulation path for circulating a coolant, the unit can be made movable even without a cooling water source such as tap water, and positive pressure is recovered by a set pressure. The operability is good because the vacuum pressure recovery using the vacuum pump can be automatically operated.
[Brief description of the drawings]
FIG. 1 is an external view of a vacuum pump unit showing one embodiment of the present invention.
FIG. 2 is a circuit diagram of a vacuum pump unit showing one embodiment of the present invention.
[Explanation of symbols]
13 Vacuum pump 16 Main circuit 17 Bypass circuit 18 Flow path switching means 28 Pump cooling means 31 Refrigerator

Claims (3)

It has a main circuit that sends the insulating gas from the inlet side to the outlet side connected to the compressor side via a vacuum pump, and a bypass circuit for the vacuum pump. When higher, the main circuit is bypassed to switch to the bypass circuit, and when low, the flow path switching means for switching to the vacuum pump of the main circuit, and pump cooling means for cooling the vacuum pump by brine, further comprising the pump cooling means, It is characterized by comprising a heat exchanger provided in a vacuum pump, a brine tank, a refrigerator for cooling the liquid in the brine tank, and a brine circulation path for supplying the coolant in the brine tank to the heat exchanger. Vacuum pump unit for insulating gas recovery. A main circuit in which a pressure regulating valve, a vacuum pump, and a cushion tank are connected between an inlet-side connection port connected to the insulating gas filling device and an outlet-side connection port connected to the compressor side, and a vacuum pump in the main circuit A bypass circuit that bypasses the gas, a flow path switching valve that switches gas from the inlet side to flow to one of the main circuit and the bypass circuit, and detects a gas pressure on the inlet side, and when the gas pressure is higher than a predetermined pressure, the bypass circuit is switched to a lower pressure. When, pressure detection means for controlling the flow path switching valve for switching to the main circuit, and a pump cooling means for cooling the vacuum pump with brine, further comprising a heat exchanger provided in the vacuum pump, It consists of a brine tank, a refrigerator that cools the liquid in the brine tank, and a brine circulation path that supplies the coolant in the brine tank to the heat exchanger. Insulating gas recovery vacuum pump unit, characterized in that accommodated in. 3. The vacuum pump according to claim 2, wherein a vacuum pump, a brine tank and a cushion tank as cooling means are arranged at the bottom of the casing, a refrigerator as the pump cooling means, and a control panel is arranged at the front of the casing. unit.

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