KR940005983B1 - Safety valve for gas boiler - Google Patents

Abstract

The safety valve for discharging abnormal over-pressure from the coiled tube at the sealed gas-fired boiler, comprises a coil spring for supporting the inlet unit at heat-exchanging media flowing passage; a lever for opening/closing the inlet unit by the valve seat (10); a slide shaft (5) having primary/secondary shafts (8)(6) for fixing the valve seat; articulated ball (7) formed at the ends of the shafts (8)(6), inserted to the groove (9) and combined with the groove; guide piece (11) fixed in front of the valve seat. The guide piece is positioned at the inlet unit (2) of the inlet (3) when the slide shaft is moved for closing or opening operations.

Description

Gas Boiler Safety Valve

1 is a schematic structural diagram of a gas boiler to which the present invention is applied.

2 is an exploded perspective view of the safety valve of the present invention.

3 is a cross-sectional view showing a state in which the safety valve of the present invention is installed in the return pipe, 3 (a) is a cross-sectional view showing a closed state of the safety valve, 3 (b) is a cross-sectional view showing an open state of the safety valve.

4 is a state in which the abnormal pressure is discharged by the safety valve of the present invention.

5 is a cross-sectional view of a conventional safety valve.

* Explanation of symbols for main parts of the drawings

1 body 2 inlet hole

2a: passage 3: entrance

4: exit 5: slide shaft

6: 1st axis 7: articular sphere

8: 2nd axis 9: insertion groove

10 packing 11: guide tube

11a: moving groove 12: fastening element

13: coil spring 14: cap bolt

15: lever 20: safety valve

21: return inlet pipe

The present invention relates to a safety valve for automatically discharging the abnormal overpressure in the coil tube of the gas boiler to discharge a certain abnormal pressure in the coil tube. Particularly, the packing is first closed by the abnormal overpressure. When restoring to the closed position, and to safely and reliably return to the packing seat, and relates to a safety valve to allow the foreign matter contained in the return or heating water is filtered and refluxed.

The heat exchanged heating water is refluxed by the pressure of the circulation pump and radiated to the channel of the heating coil embedded in the floor of the room connected to the hermetic gas boiler.

If the sealed gas boiler is subjected to overpressure above the certain pressure in the heating coil channel due to abnormality of combustion and abnormality of piping such as clogging of the pipe, there is a problem that the breakdown of the apparatus and the vulnerable part of the heating pipe are ruptured by the overpressure. It was required to install a safety valve that is modified when an abnormal overpressure occurs on one side of the heating coil, mainly the return side valve.

The safety valve for removing the over-pressure is usually using an automatic safety valve, such automatic safety valve has an inlet hole connected to the water channel, the packing is installed on the outlet side of the exhaust hole, the slide shaft installed in the center of the packing Inserting a fixing spring for supporting the coil spring and the slide shaft, the fastening cap was equipped with a screw thread of the outlet.

Such a conventional safety valve has a configuration in which the distance "a" from the outlet of the inlet hole to the exhaust hole is large and the area ratio of the inlet hole inner diameter D and the valve tube outer diameter D 'of the valve body is small. When the overpressure occurred, the valve seat was frequently opened and closed due to a small amount Q of overpressure escaped through the outlet of the inlet hole.

Frequently opening and closing the valve seat increases the fatigue of the coil spring to change the value of the spring modulus K to promote the fatigue limit.

In addition, after the valve seat is subjected to abnormal overpressure and repeatedly discharges the heating quantity Q due to the overpressure P and the overpressure, the valve seat retreats beyond the fatigue limit of the coil spring when it comes back and comes in close contact with the point corresponding to the original position. As a result of the loss of elasticity, it is often caused by structural defects that it is not in close contact with the correct position.

In addition, the position where the valve seat is operated is not constant, and there is a phenomenon in which water is leaked in a state where the outlet is interrupted.

The reason for the above-mentioned problem is that first, the distance "a" from the outlet of the inlet hole to the exhaust hole is large, and secondly, the area ratio of the inner diameter D of the inlet hole and the outer diameter D 'of the valve plate is small. Comes from.

That is, the valve plate is frequently operated because the distance to the exhaust hole is long and the area ratio is small, so it takes time to escape.

In order to solve this problem, the gap between the valve passage and the diameter of the packing should be maintained at the minimum resistance interval, and jointed to the slide shaft so that the amount of displacement due to the point rotation does not interfere with the forward and backward movement of the slide. In order to close the inlet more reliably and reliably upon return, it is required to have a guide tube moved along the inlet in the valve seat so that it is always returned to the correct position.

Therefore, the present invention forms the area ratio between the valve seat and the passage of the valve to a size having a minimum resistance when moving the fluid, and temporarily passes all the overpressure through the length of the distance "a" from the outlet of the inlet hole to the exhaust hole The slide shaft is formed to have a suitable length, and the slide shaft to which the valve seat is moved by lever operation is formed to have a joint by the middle, and the guide moves to be in contact with the inner diameter of the valve seat inlet hole for opening and closing the inlet hole of the valve. To provide a safety valve provided with a stand.

By providing the safety valve as described above, any abnormal overpressure generated in the heating coil pipe will be released through the valve immediately, and the valve seat, which has opened the inlet of the inlet, will return to its place correctly and close the inlet in a stable state. To maintain the confidentiality of the channel in the coil tube.

Referring to the safety valve of the present invention in detail with the accompanying drawings as follows.

The inlet hole 2 and the passage 2a are formed in a straight line in the body 1 of the safety valve 20 inserted into the return side inlet pipe 21 of the hermetic gas boiler so as to pass through the passage 2a. And another through hole connected to the passage 2a by passing the passage horizontally through the body 1 so that the valve seat 10 and the compression coil spring 13 are provided in the passage 2a. The cap seat 14 of the slide shaft 5 is screwed to the body 1 by inserting the provided slide shaft 5 into the body 1 so that the valve seat 10 of the slide shaft 5 enters the inlet of the passage 2a. The valve seat 10 opens and closes the inlet 3 of the passage 2a by manipulating the lever 15 connected to the tip of the slide shaft 5 with the pin 16 so that the valve seat 10 is elastically blocked. In another configuration, the tube 2a formed in the valve body 1 is formed perpendicularly to the passage 2a provided with the inlet 3 through which the valve seat 10 opens and closes. That is, to form a forming position of the outlet (4) close to the inlet (3).

In more detail, the distance (a ') from the tip of the inlet (3) to the central axis of the outlet (4) is provided as close as possible, but this close distance is within the fatigue limit of the coil spring (13).

Therefore, the opening and closing operation of the valve seat 10 can be always performed with a constant ability even in a repetitive stretching operation in which the elastic constant such as the spring constant k is not changed.

Then, the ratio of the outer diameter d 'of the valve seat 10 for opening and closing the inlet 3 and the diameter d of the passage 2a is also adjusted so that the maximum escape amount Q is released at one time opening. To have.

The area ratio of the above is the most suitable that the area of the valve seat is about 40 ~ 45% of the area in the passage, as a result of the test by its own inspection and measuring equipment.

The slide shaft 5 provided with the valve seat 10 has a first shaft 8 for connecting the lever 15 to the pin 16 on the outer surface of the cap bolt 14 and a second shaft for installing the valve seat 10. (6) Separated and connected.

The connection between the first shaft 8 and the second shaft 6 forms a spherical articular sphere 7 at one end, and an insertion groove 9 at the other end thereof, such as a joint structure. ) Is inserted into the insertion groove (9), and narrowed the inlet of the insertion groove (9) is formed so that the joint sphere (7) does not fall out is connected.

The rear end of the shaft (6) having the above-described articular sphere is formed by digging the seat groove (6a) for the valve seat, and by digging a screw groove in the center of the rear end to connect the guide piece (11).

The guide piece 11 is formed in such a size that its outer diameter is inserted into the inner diameter of the inlet hole 2, and the inlet 3 and the guide piece 11 are removed when the valve seat 10 is moved by cutting out a portion 11a around the outer diameter. It is to be provided with a gap for the fluid or gas to escape between the position (11a) of the cut.

In particular, the uncut portion of the guide piece 11 does not escape from the inlet hole 2 even when the valve seat 10 moves so that the valve seat 10 guides into position when the inlet 3 is closed. Achieve.

In the figure, reference numeral 12 is a screw for coupling the guide piece 11 to the second shaft 6, 22 is a filtering net for filtering foreign matter from the heating water, and 23 is a safety valve fixed to the water inlet 21. It is a screw for.

According to the present invention, the slide shaft 5 includes a valve seat 10, a guide piece 11, and a compression coil spring 13 provided in the passage 2 of the body 1. Cap bolt 15 is fastened to the end of the passage 2a, and the valve seat 10 is normally blocking the inlet 3 of the inlet hole 2, and the abnormal overpressure in the heating coil pipe and the boiler body not shown. When this is formed, the overpressure is moved to the inlet hole (2) of the safety valve 20 installed on the side of the water.

At this time, the valve seat 10 blocking the inlet 3 of the inlet hole 2 is in close contact with the inlet 3 by the elastic force of the compression coil spring 13, but because the abnormal overpressure is larger than the compression coil spring elastic force. The compression coil spring 13 is contracted to receive a heating abnormal pressure P from the inlet 3 to the valve seat 10 through the valve seat 10, and is formed between the cutout groove 11a of the guide piece 11 and the inlet 3. When the gap is formed, the overpressure is discharged to the outside through the outlet (4) instantaneously.

As described above, the abnormal overpressure exiting to the outside has a large difference in cross-sectional area between the valve seat 10 and the passage 2a, and the distance a 'from the inlet 3 to the outlet 4 is short. It can be seen that the flow rate of the fluid increases proportionally in the state.

The flow rate Q is proportional to the passage cross-sectional area of the safety valve when the fluid velocity V is the same.

Q = A.V (Q: Flow Rate

A: Cross section of valve seat

V: fluid velocity)

Is certified.

In this way, after all of the abnormal overpressure has been released from the inlet 3 to the outlet 4 at once, the pressure in the heating coil pipe becomes smaller than the elastic force of the compression coil spring 13, so that the restoring force of the compression coil spring 13 is the valve seat 10. ) Is moved to the inlet (3) position.

When the valve seat 10 is moved to the inlet position, the valve seat 10 is guided by the guide piece 11 because the guide piece 11 installed in front of the valve seat 10 is fitted in the inlet hole 2. Received to close the inlet (3) of the inlet (2) correctly.

In order to artificially withdraw the overpressure or the heating water inside the heating coil pipe, pull the lever 16 connected to the slide shaft 5 to rotate the point as shown in FIG. 3 (b). Together, the slide shaft 5 is pulled out to open the inlet 3 as described above. This is called draining.

Thereafter, when the lever 16 is rotated to its original position, the inlet is closed. In the process of moving the slide shaft pulled by the lever, the first shaft 8 does not move horizontally by the point rotation of the lever. Although a failure occurs, it is not transmitted to the second axis 6 and is corrected to a horizontal movement state by the overdrive portion, that is, the joint sphere 7 of the second axis 6.

As described above, the present invention can be in close contact with the accurate return and return of the packing by the guide piece, which is always located at the joint motion and the inlet of the slide shaft, the value of the passage cross-sectional area difference between the valve seat and the safety valve and the inlet and outlet It has a configuration that the fluid flow is discharged to the maximum amount between the distance between the discharge, the overpressure in the coil pipe is sufficiently escaped to the outside air to satisfy the escape amount, the efficiency of the safety valve is remarkably improved. In addition, the overpressure is automatically adjusted and the heating water can be removed by lever operation.

In addition, the result of the valve seat being moved to the correct closed position is to prevent the malfunction and water leakage in advance.

Claims (1)

In order to discharge the abnormal overpressure of the hermetic gas boiler, the inlet of the passage in the flow path of the heat exchange mobile medium is elastically supported by the coil spring, and the valve seat 10 is opened and closed by the valve seat according to the position of the lever, and the valve seat 10 is fixed to the tip. The slide shaft 5 is composed of a first shaft 8 and a second shaft 6, and the joint hole 7 formed at the end and the tip of the first and second shafts 8, 6 is inserted groove 9 In the formation of the safety valve coupled to the deflection freely, the guide piece 11 is fixed to the front of the valve seat 10 so that the guide piece 11 of the inlet (3) when opening and closing the slide shaft (5) A safety valve for a closed gas boiler configured to be located in the inlet hole (2).