JP2004060788A - Gas piping shutoff device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a gas piping shutting off device capable of shutting off a gas flow channel at occurrence of a fire or the like. <P>SOLUTION: In the gas piping shutoff device, a socket 5 for interconnecting gas pipes 1 and 2 is constituted by a cylindrical member made of cast iron. An escape groove 6A for screw machining is formed in the center of the inner peripheral surface of the socket 5, and an expansible fire-proofing packing material 10 is arranged in the escape groove 6A. This packing material 10 is formed of an expansible material containing graphite. When the fire or the like occurs to increase temperature of the gas pipes 1 and 2 and the socket 5, the packing material 10 in the socket 5 expands so as to extrude into the gas flow channel, and the gas flow channel is buried with the expanding packing material 10' to block the flow channel. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an apparatus for blocking gas flowing in a pipe member such as a city gas pipe. In particular, the present invention relates to a gas pipe shutoff device that can shut off a gas flow path in the event of a fire or the like.
[0002]
[Prior art]
The city gas pipe is made by connecting steel or plastic pipes with a socket or the like, and incorporating a gas stopper, a gas meter, and the like. The gas stopper is installed at a predetermined position of the gas flow path, such as a meter entry side.
[0003]
[Problems to be solved by the invention]
By the way, when a fire occurs around the gas meter, it is expected that the gas tap on the gas meter entry side cannot be closed manually. In such a case, when the temperature of the gas meter rises, the meter and other parts may be damaged and gas may leak out. In particular, when the gas meter is made of an aluminum casting, the gas meter is susceptible to heat and may be melted. Therefore, there is a need for a means for shutting off the flow of gas inside the pipe even when the temperature rises in a fire or the like.
[0004]
The present invention has been made in view of such a problem, and an object of the present invention is to provide a gas pipe shutoff device that can shut off a gas flow path in the event of a fire or the like.
[0005]
[Means for Solving the Problems]
In order to solve the above-mentioned problem, a gas pipe cutoff device according to the present invention provides a gas pipe having an inflatable gas at a temperature rise in a portion outside an effective flow path section along a gas flow path side wall in a pipe member of a gas pipe. A flow path blocking member is provided.
[0006]
According to this gas pipe blocking device, when a fire or the like occurs and the gas pipe is heated, the blocking member in the pipe member expands so as to protrude into the gas flow path, and the gas flow path is expanded by the expanded blocking member. It is buried and the channel is blocked.
[0007]
In the gas pipe cutoff device of the present invention, the pipe member may be a socket, and the ring-shaped cutoff member may be disposed in a threaded relief groove in the socket.
Further, the pipe member may be a gas stopper, and the ring-shaped blocking member may be disposed in a relief groove for threading in the gas stopper.
[0008]
In these cases, a gas cutoff function can be added to the existing pipe member because the relief groove for threading the pipe member is used as a space for disposing the gas flow path blocking member. That is, there is no need to process additional parts or existing parts.
[0009]
In the gas pipe shutoff device of the present invention, the pipe member is a joint, an adapter having a ring groove is interposed in the joint, and the shutoff member can be arranged in the ring groove.
In this case, the function of shutting off the gas flow path can be easily provided by adding only the adapter and the gas flow path shut-off member to the joint.
In the gas pipe shutoff device of the present invention, the pipe member may be a meter joint, and the ring-shaped shutoff member may be arranged in a groove provided in the meter joint.
[0010]
In the gas pipe cutoff device of the present invention, the pipe member is an elbow or a bend having at least one female screw, and is provided in a space in the female screw side joint located at the back of the male screw of the female screw / male fitting assembly. The blocking member may be disposed.
In this case, the blocking function of the pipe member can be provided without narrowing the gas flow path by the blocking member.
In the gas pipe cutoff device of the present invention, the gas flow passage cutoff member may be made of an expandable fireproof packing material containing graphite.
In addition, such a packing material has been conventionally used as an auxiliary sealing member in the event of a fire, but there has never been proposed a method of closing the gas flow path itself as in the present invention.
[0011]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, description will be made with reference to the drawings. Note that the terms up, down, left, and right in the following description refer to the up, down, left, and right directions in each figure.
[First embodiment; when the pipe member is a socket]
FIG. 1 is a sectional view showing a gas flow path (gas pipe, socket and packing material) according to a first embodiment of the present invention. (A) is a diagram showing the packing material before expansion (normal time), and (B) is a diagram showing the packing material after expansion (fire or the like).
[0012]
FIG. 1 shows left and right gas pipes 1 (left) and 2 (right), a socket 5 (center in the figure) connecting these gas pipes 1 and 2 in the axial direction, and an inflatable tube arranged in the socket 5. A refractory packing material 10 is shown.
Each of the gas pipes 1 and 2 is a steel pipe having a circular cross section. Male screws 1a and 2b are cut on the outer peripheral surfaces of the connection ends of the gas pipes 1 and 2, respectively. Each of the male screws 1a and 2b is a tapered screw whose diameter is gradually reduced toward the pipe end.
[0013]
The socket 5 connecting the gas pipes 1 and 2 is a cylindrical member made of cast iron or the like. On the inner peripheral surface near both ends of the socket 5, female threads 5a and 5b screwed with the male threads 1a and 2b of the gas pipes 1 and 2 are formed. Each of the female screws 5a and 5b is formed by threading from both ends (left and right end surfaces in the figure) of the socket 5 toward the center. In the center of the inner peripheral surface of the socket 5, an escape groove 6A for threading the female screws 5a and 5b is formed.
[0014]
An intumescent refractory packing material 10 is arranged in the thread relief groove 6A of the socket 5. The place where the packing material 10 is disposed is a part outside the effective flow path cross section along the gas flow path side wall. The packing material 10 is formed from an expandable material containing the aforementioned graphite. The specific dimensions and the like of the packing material 10 will be described later in detail.
[0015]
Normally, the packing material 10 is arranged along the inner peripheral surface of the threading relief groove 6A of the socket 5 while maintaining the ring shape as shown in FIG. At this time, a sufficient space (gas flow hole) is secured inside the packing material 10, so that there is no hindrance to the gas flow. Here, when a fire or the like occurs and the temperature of the gas pipes 1, 2, and the socket 5 rises, the packing material 10 in the socket 5 expands so as to protrude into the gas flow path, and as shown in FIG. The flow path is buried with the expanded packing material 10 ', and the flow path is blocked. Thereby, the gas flowing through the gas flow path is shut off.
[0016]
In the first embodiment, since the relief groove 6A for threading of the socket 5 is used as a space for disposing the packing material 10, there is no need to change or add parts other than disposing the packing material 10 in the existing socket 5. There is an advantage that there is.
[0017]
Next, a fire resistance test of the gas flow channel of the first embodiment will be described.
FIG. 2 is a diagram showing a piping line used for the fire resistance test according to the present invention.
The purpose of the fire resistance test is to obtain a measure of the volume of the packing material 10 necessary for blocking the gas flow path. The pipe 1 used for the test pipe line L shown in FIG. 2 is a 3 / 4B (20A) pipe. At the left end of the piping line L, an air supply source 8 is provided. In the middle of the piping line L, the same sockets 5A and 5B as those shown in FIG. 1 are incorporated. The above-mentioned packing material 10 is arranged in the socket 5A.
[0018]
The piping line L in FIG. 2 is arranged in a furnace where the line on the right side of the socket 5B (the right side of the symbol X) is kept at 800 ° C. 300 liter / h of air was supplied from the air supply source 8 to the pipe line L. Then, the right side of the pipe line L was inserted into a furnace and left for 30 minutes, and a change in the flow rate of air from the pipe line was measured. The air flow rate was measured by a flow meter at a flow rate of 1 minute every 5 minutes (4 to 5 minutes in the case of 5 minutes), and was converted into a flow rate per hour.
[0019]
The packing material 10 used in this test has an outer diameter of 27 mm (same as the inner diameter of the relief groove 6A for threading of the socket 5 (see FIG. 1)), and an inner diameter of 21 mm (same as the inner diameter of the 3 / 4B pipe). , And the thickness is 2.2 mm.
[0020]
The test results are as follows.
(1) When the number of the refractory packings in the socket was four, the air in the piping was shut off 3 minutes and 15 seconds after the test piping was put in the furnace.
(2) When the number of refractory packings in the socket was 5, the air in the pipe was shut off 2 minutes and 50 seconds after the test pipe was put in the furnace.
[0021]
From these test results, under the condition of flowing air at a flow rate of 300 liters / h using a 3 / 4B pipe, the volume of the packing material is 1990.5 mm ³ (four packing materials having the dimensions described above), and the flow of air is reduced. I found that I could shut it off. Furthermore, it seems that there is a volume of the packing material suitable for the conditions for other pipes and flow rates. In the above experiment, the air flowing through the pipe was air. However, since the air oxidizes the packing material, it is considered that the test was conducted under more severe conditions than the actual situation in the gas pipe.
[0022]
[Second embodiment: When the pipe member is a gas stopper]
FIG. 3 is a cross-sectional view showing a gas flow path (gas pipe, gas stopper, and packing material) according to a second embodiment of the present invention.
FIG. 3 shows the same gas pipes 1 (left side in the figure) and 2 (right side in the figure) as in the first embodiment. In the second embodiment, a pipe member (center in the figure) connecting the two gas pipes 1 and 2 in the axial direction is a gas plug 20, and two inflatable refractory packing materials 11 and 12 are provided in the gas plug 20. Are located.
[0023]
The gas stopper 20 includes a socket part 21 having a substantially cylindrical shape. On the inner peripheral surface near both ends of the socket portion 21, female screws 21 a and 21 b screwed with the male screws 1 a and 2 b of the gas pipes 1 and 2 are formed. Each of the female threads 21a and 21b is formed by threading from both ends (left and right end faces in the drawing) of the socket 21 toward the center. In the inside of the socket part 21, relief grooves 22 </ b> A and 22 </ b> B for screw processing are formed in the back of the female screws 21 a and 21 b, respectively. Inflatable refractory packing materials 11 and 12 are arranged in these threaded relief grooves 22A and 22B. Each of the packing materials 11 and 12 is made of the same material containing expanded graphite as in the first embodiment.
[0024]
On the outside of the central portion of the socket portion 21 (upper side in the figure), a projecting portion 23 projecting in a cylindrical shape is integrally formed. The overhang 23 is provided with a lid 25 rotatably. A lever 26 is attached to the lid 25. In the socket 21, a shaft-shaped valve 27 is attached to the lower surface of the lid 25. The upper end of the valve body 27 is coupled to the lower surface of the lid 25 by concave and convex engagement, and the lower end is slidably fitted in the concave portion 24 in the socket portion 21. At the center of the valve body 27, a gas flow hole 27a penetrating in the radial direction is formed.
[0025]
In a state shown in FIG. 3 (a state in which the direction in which the lever 26 extends and the direction in which the gas pipe 2 extends), the gas flow holes 27 a of the valve body 27 are open into the gas pipes 1 and 2. At this time, the gas flows from the gas pipe 1 to the gas pipe 2 through the gas flow holes 27a of the valve body 27 (or, conversely, flows from the gas pipe 2 to the gas pipe 1). In this state, when the lever 26 is turned and the direction in which the lever 26 extends and the direction in which the gas pipe 2 extends are vertically intersected, the gas flow hole 27 a of the valve body 27 is closed by the inner surface of the socket 21. At this time, the gas flow between the gas pipe 1 and the gas pipe 2 is shut off by the valve body 27.
[0026]
In the second embodiment, as in the first embodiment, when a fire or the like occurs, the packing materials 11 and 12 expand in the socket portion 21 so as to protrude into the gas flow path, and the gas flow path expands. And the flow path is blocked. Thereby, the gas flowing through the gas flow path is shut off. Furthermore, in order to use the clearance grooves 22A and 22B for threading of the socket portion 21 as spaces for arranging the packing materials 11 and 12, modifications and additions are made in addition to arranging the packing materials 11 and 12 in the existing gas stopper 20. There is an advantage that no component is required.
Also in the case of the second embodiment (gas stopper 20), the volume of the packing material can be set appropriately by performing the test as described in the first embodiment.
[0027]
[Third embodiment: When the pipe member is an adapter]
FIG. 4 is a sectional view showing a gas flow path (gas pipe, gas meter connection port, joint, adapter, and packing material) according to the third embodiment of the present invention.
FIG. 4 shows the gas pipe 3 (upper part in the figure), the connection port 7 of the gas meter (lower part in the figure), and the adapter 40 between the gas pipe 3 and the connection port 7. The adapter 40 is provided with an intumescent refractory packing material 13 which plays the same role as the packing materials 10, 11, 12 of the first and second embodiments. This packing material 13 is also formed of a material containing expanded graphite.
[0028]
On the outer peripheral surface near the end of the gas pipe 3 (closer to the lower end in the figure), a large diameter portion 3A having a diameter larger than the outer diameter of the pipe is formed. A groove 3B for engaging the stop ring 31 is formed in the large diameter portion 3A along the circumferential direction. The depth of the groove 3B is smaller than the cross-sectional diameter of the stop ring 31. A small diameter portion 3D having a smaller diameter than the outer diameter of the tube is formed between the large diameter portion 3A and the tube end face 3C.
[0029]
A sheet packing material 35 is disposed at a boundary step 3E between the outer peripheral surface of the small diameter portion 3D and the lower end surface of the large diameter portion 3A. A cap nut 33 is attached to the large diameter portion 3A of the gas pipe 3. The cap nut 33 is prevented from coming off from the pipe end by hitting the stop ring 31. The cap nut 33 is screwed into a male screw 41 of an adapter 40 described later. The cap nut 33 serves as a joint to the connection port 7 of the gas meter when the adapter 40 is not provided.
[0030]
A tubular adapter 40 is attached to the connection port 7 of the gas meter. On the outer peripheral surface near the upper end of the adapter 40, a male screw 41 screwed to the cap nut 33 is formed. On the inner peripheral surface near the lower end of the adapter 40, a female screw 42 to be screwed to the male screw 7a of the connection port 7 is formed. A hexagonal outer peripheral surface 43 that protrudes in a hexagonal shape is formed on the outer peripheral surface near the lower end of the adapter 40. The hexagonal outer peripheral surface 43 is for engaging a tool such as a spanner when the adapter 40 is tightened to the connection port 7.
[0031]
An arrangement groove 45 for arranging the expandable refractory packing material 13 is formed on the inner peripheral surface of the adapter 40 in the central portion in the axial direction. The packing material 13 plays the same role as the packing materials 10, 11, and 12 of the first and second embodiments. On the inner side near the lower end of the adapter 40, a groove 47 is dug into the inner side of the female screw 42. The groove 47 is located between the inner peripheral surface of the adapter 40 and the outer peripheral surface 43 of the hexagon. The sheet packing material 36 is disposed in the groove 47.
[0032]
In the connection state of the gas pipe 3, the adapter 40 and the connection port 7 of the gas meter as shown in FIG. 4, the upper sheet packing material 35 is sandwiched between the lower surface of the large diameter portion 3 </ b> A of the gas pipe 3 and the upper end face of the adapter 40. It is arranged in a state where On the other hand, the lower sheet packing material 36 is disposed between the bottom surface of the groove 47 of the adapter 40 and the end face of the connection port 7 of the gas meter. The expandable refractory packing material 13 is normally arranged along the arrangement groove 45 of the adapter 40.
[0033]
Similarly to the first and second embodiments, the gas passage of the third embodiment also expands so that the packing material 13 in the arrangement groove 45 of the adapter 40 protrudes into the gas passage when a fire or the like occurs, The gas flow path is filled with the expanded packing material 13 to block the flow path. In the case of the third embodiment, the gas flow path can be easily shut off by adding only the adapter 40 (including the packing material 13) between the gas pipe 3 and the connection port 7 of the gas meter.
[0034]
[Fourth embodiment: When the pipe member is a gas meter connection joint]
FIG. 5 is a cross-sectional view showing a gas flow path (gas pipe, female male bend, gas meter connection port, gas meter connection joint, and packing material) according to the fourth embodiment of the present invention.
FIG. 5 shows a gas pipe 3 (left part in the figure), a connection port 7 of the gas meter (right part in the figure), a female male bend 61 and a gas meter connection joint 51 between the gas pipe 3 and the connection port 7. I have. In a groove 52a provided in an end portion 52 of the gas meter connection joint 51, an intumescent refractory packing material 55 having the same function as the packing materials 10 to 13 of the first to third embodiments is provided. ing. This packing material 55 is also formed of a material containing expanded graphite.
[0035]
A female screw 61b of the female male bend 61 is screwed to an end of the gas pipe 3. The male screw 61 a (the end opposite to the female screw 61 b) of the female male bend 61 is screwed to a female screw 53 a in an end 53 of the gas meter connection joint 51. An end 52 (an end opposite to the end 53) of the joint 51 is connected to a gas meter connection port with a cap nut 33 via a stop ring 31 and a sheet packing material 35 similar to the third embodiment. 7 is connected. In the fourth embodiment shown in FIG. 5, no adapter is provided unlike the third embodiment shown in FIG.
[0036]
In the gas flow path of the fourth embodiment, the expandable fireproof packing material 55 disposed in the groove 52a of the gas meter connection joint 51 expands when a fire or the like occurs and shuts off the gas flow path. That is, when a fire or the like occurs, the packing material 55 expands so as to protrude into the gas flow path, and the gas flow path is buried with the expanded packing material 55 to block the flow path.
[0037]
[Fifth embodiment; a case where the pipe member has a fitting assembly]
FIG. 6 is a sectional view showing an example of a gas flow path (gas pipe, male / female joint, packing material, and gas meter connection port) according to a fifth embodiment of the present invention.
FIG. 7 is a sectional view showing another example (a packing material modification) of the gas flow channel according to the fifth embodiment.
FIGS. 6 and 7 show the gas pipe 3 (the left part of the figure), the connection port 7 of the gas meter (the lower part of the figure), and the joint between the gas pipe 3 and the connection port 7 (the male joint 71 and the female joint 73). )It is shown. In the space inside the female joint 73 at the back of the male joint 71, packing materials 75 and 76 are arranged.
[0038]
The packing material 75 shown in FIG. 6 is an expandable refractory packing material formed from a material containing expanded graphite. This packing material 75 also plays a role similar to each packing material of the above-described embodiment. The packing material 75 has an outer shape of a truncated cone, and is formed so that the outer peripheral surface is along the inner peripheral surface of the female joint 73. The inner diameter of the packing material 75 is substantially the same as the inner diameter of the male joint 71.
[0039]
The packing material 76 shown in FIG. 7 is also formed of a material containing expanded graphite, and plays a role similar to each packing material of the above-described embodiment. The packing material 76 is formed larger (longer) than the packing material 75, and has a shape that covers substantially the entire inner peripheral surface of the elbow portion of the female joint 73. The inner diameter of the packing material 76 is also substantially the same as the inner diameter of the male joint 71.
[0040]
Such a packing material 75 (76) also expands when a fire or the like occurs and shuts off the gas flow path, similarly to the packing materials of the above-described embodiments. That is, when a fire or the like occurs, the packing material 75 (76) expands so as to protrude into the gas flow path, and the gas flow path is filled with the expanded packing material 75 (76) and the flow path is shut off. By using such a packing material 75 (76), a blocking function can be imparted without narrowing the gas flow path.
[0041]
【The invention's effect】
As apparent from the above description, according to the present invention, it is possible to provide a gas pipe shutoff device capable of shutting off a gas flow path in the event of a fire or the like.
[Brief description of the drawings]
FIG. 1 is a sectional view showing a gas flow path (gas pipe, socket and packing material) according to a first embodiment of the present invention. (A) is a diagram showing the packing material before expansion (normal time), and (B) is a diagram showing the packing material after expansion (fire or the like).
FIG. 2 is a diagram showing a piping line used for a fire resistance test according to the present invention.
FIG. 3 is a cross-sectional view showing a gas flow path (gas pipe, gas stopper, and packing material) according to a second embodiment of the present invention.
FIG. 4 is a cross-sectional view showing a gas flow path (gas pipe, gas meter connection port, joint, adapter, and packing material) according to a third embodiment of the present invention.
FIG. 5 is a cross-sectional view illustrating a gas flow path (gas pipe, female male bend, gas meter connection port, gas meter connection joint, and packing material) according to a fourth embodiment of the present invention.
FIG. 6 is a sectional view showing an example of a gas flow path (gas pipe, male / female joint, packing material, and gas meter connection port) according to a fifth embodiment of the present invention.
FIG. 7 is a sectional view showing another example (a packing material modification) of the gas flow channel according to the fifth embodiment.
[Explanation of symbols]
1, 2, 3 Gas pipe L Piping line 5 (5A, 5B) Socket 6A Relief groove for screw processing 7 Gas meter connection port 8 Air supply source 10, 11, 12, 13, 55, 75, 76 Expandable fireproof packing material DESCRIPTION OF SYMBOLS 20 Gas stopper 21 Socket part 22A, 22B Relief groove for screw processing 23 Projection part 25 Cover 26 Lever 27 Valve 27a Gas flow hole 33 Cap nut 31 Stop ring 35, 36 Seat packing material 40 Adapter 45 Arrangement groove 51 Gas meter connection Joint 52a Groove 61 Female male bend 71 Male joint 73 Female joint

Claims (7)

Gas pipe shut-off characterized in that a gas flow path shut-off member having expandability at the time of temperature rise is arranged at a portion outside a cross section of an effective flow path along a gas flow path side wall in a pipe member of a gas pipe. apparatus. 2. The gas pipe shut-off device according to claim 1, wherein the pipe member is a socket, and the ring-shaped shut-off member is arranged in a threading relief groove in the socket. 2. The gas pipe shut-off device according to claim 1, wherein the pipe member is a gas plug, and the ring-shaped shut-off member is disposed in a relief groove for threading in the gas plug. 2. The gas pipe shutoff device according to claim 1, wherein the pipe member is a joint, an adapter having a ring groove is interposed in the joint, and the shutoff member is arranged in the ring groove. . 2. The gas pipe cutoff device according to claim 1, wherein the pipe member is a meter joint, and the ring-shaped shutoff member is disposed in a groove provided in the meter joint. The pipe member is an elbow or a bend having at least one female screw, and the blocking member is arranged in a space in a female screw side joint located at the back of the male screw of the female screw / male screw fitting assembly. The gas pipe cutoff device according to claim 1, wherein The gas pipe cutoff device according to any one of claims 1 to 6, wherein the gas flow path cutoff member is made of an expandable refractory packing material containing graphite.

Images