JPS605548Y2 - Pressure relief device for oil-filled electrical equipment - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a pressure relief device attached to oil-filled electrical equipment to protect the case of the equipment in the event of a sudden increase in internal pressure caused by an internal accident.

An example of this type of device that has been commonly used in the past is the first one.
It is as shown in the figure.

In the figure, reference numeral 1 denotes an oil-filled electrical device, and a pressure relief pipe 2 led out from the top surface releases the pressure oil to a drain oil tank 8 through an oil drain pipe 5 when the oil pressure inside the device 1 suddenly increases. Therefore, the aim is to prevent the equipment case from being destroyed due to an increase in oil pressure.

Therefore, a vertical tubular safety valve 3 and an attached rupture disc 4 are connected to the tip of the drooping part of the pressure relief pipe 2, and a vertical oil drain pipe 5 is connected below it.
are connected, and the lower end of the pipe 5 is connected to a drain oil tank 8 buried in the floor surface.

The oil drain pipe 5 is connected to the case of the device 1 at two locations, upper and lower, by mounting pieces 6, respectively.

Details of the safety valve 3 and the rupture disc 4 are as shown in FIG.

That is, a valve opening is formed in the upper end flange 3a of the vertical pipe that covers the exterior of the safety valve 3, and a valve element 11 is provided vertically slidably to open and close the valve seat located around the lower side of the valve opening.

A coil spring 12 is inserted between the upper end top plate of the valve body 11 and the upper peripheral portion of the valve opening.

A vertical connecting pipe 9 for supporting the rupture disc 4 is provided below the safety valve pipe 3, and in the case of FIG. 1, an oil drain pipe 5 is connected under this pipe 9 by flange connection.

The rupture disc 4 is installed between the lower end flange 3b of the pipe 3 and the upper end flange 9a of the pipe 9, and the needle-like lower end of the valve body 11 is arranged close to the upper surface of the rupture disc 4.

Therefore, when the oil pressure or air pressure in the pressure relief pipe 2 is low, the valve body 11 is pushed up by the force of the spring 12 to close the valve opening, but when the oil pressure in the device 1 increases excessively, the valve body 11 is pushed down against the force of the spring 12 to open the valve opening, and at the same time, the lower end of the valve body breaks through the plate 4, allowing high-pressure oil to flow downward.

In the conventional pressure relief device shown in FIG. 1, when replacing the rupture disc 4 or performing regular inspection thereof, first loosen the connection between the oil drain pipe 5 and the mounting piece 6, and then pull down the oil drain pipe 5. It was necessary to replace or inspect it, and once that was completed, the operation had to be reversed again.

However, since the oil drain pipe 5 normally weighs about 100 kg and has a length of about 100 kg, the above-mentioned work has the disadvantage of requiring a great deal of labor and time.

The present invention aims to eliminate the above-mentioned drawbacks, and one embodiment thereof will be described with reference to FIG. 2.
The safety valve 3, rupture disc 4, and pipe 9 are the same as those shown in the first diagram, but a vertical tubular spacer 7 is inserted between the support pipe 9 of the rupture disc 4 and the oil drain pipe 5 below it. The present invention is characterized in that the lower end flange of the seat is inclined obliquely with respect to the tube axis direction.

In FIG. 3 showing the details, the upper end flange 7a of the spacer 7 is perpendicular to the tube axis direction as usual, but the lower end flange 7b is made to be inclined obliquely to the tube axis direction.

The upper end flange 7a is connected to the lower end flange 9b of the connecting pipe 9 that supports the rupture disc 4 via a backing, and the lower end flange 7b is connected to the upper end flange 5a of the oil drain pipe 5, which is formed at an angle equivalent to this, and the backing. are contact-coupled through.

Note that in FIG. 3, illustrations of bolts and the like that tighten between the upper and lower flanges are omitted.

By inserting the spacer 7 with an inclined lower end flange between the support pipe 9 of the rupture disc 4 and the oil drain pipe 5 as described above, when replacing the rupture disc 4, the oil drain pipe 5 can be left as is. Since it is now possible to easily pull apart only the spacer 7 to the side in this state, the troublesome operation of loosening the connection between the oil drain pipe 5 and the mounting piece 6 and pulling down the pipe 5 as in the conventional method is eliminated. This becomes unnecessary and improves work efficiency.

As a variant, in the illustrated embodiment the lower end flange 7b of the spacer 7
Although the upper end flange 7a may be provided with a similar inclination instead, the lower end flange 9b of the connecting pipe 9 will be provided with a similar inclination.

Further, both the upper end flange 7a and the lower end flange 7b may be provided with inclinations in opposite directions, thereby making it easier to pull the spacer 7 apart laterally.

According to the present invention, the work of replacing or inspecting the rupture disc in this type of pressure relief device is facilitated, and the work efficiency is improved.

[Brief explanation of the drawing]

FIG. 1 is a schematic elevational view of a conventional device, FIG. 2 is a schematic elevational view of a device according to the present invention, and FIG. 3 is a cross-sectional elevational view of the main parts. 1... Oil-filled electrical equipment, 2... Pressure relief pipe,
3...Safety valve, 4...Rupture disc, 5...
...Drain pipe, 6...Mounting piece, 7...
- Spacer, 7a, 7b...Flange.

Claims (1)

[Scope of utility model registration request] A vertical tubular safety valve with a rupture disc is connected to the tip of the hanging part of the pressure relief pipe led out from the oil-filled electrical equipment, and a vertical tubular spacer is inserted between this safety valve and the vertical oil drain pipe below it. is a pressure relief device for oil-filled electrical equipment, characterized in that a flange at one end thereof is inclined obliquely with respect to the pipe axis direction.