JP2014000258A - Flame arrester - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a flame arrester which can be easily made, worked and handled by using a flame arrester element made of an inorganic fiber fabric and which has a simple structure hardly causing clogging and facilitating management.SOLUTION: A flame arrester is provided in a combustible gas channel P by a flame arrester element which permits the passage of combustible gas by meshes formed in an inorganic fiber fabric and which inhibits the passage of a flame caused by burning of the combustible gas, and attachment means for arranging the flame arrester element in such a manner that it crosses the combustible gas channel.

Description

  The present invention relates to a flame arrester that prevents passage of a flame and a shock wave generated by combustion of a combustible gas in a flow path.

  If ignition occurs for any reason in a combustible fluid transport pipe, storage tank, or the like, the combustible gas may be ignited, resulting in rapid combustion, that is, deflagration or detonation. This can cause major accidents such as the propagation of flames to pipes and storage tanks, damage to equipment due to shock waves, and the occurrence of secondary disasters associated with equipment damage.

  In order to prevent such an accident, a flame arrester is used to prevent a flame and a shock wave from propagating through the flow path when combustion occurs in the flow path of the combustible fluid. The flame arrester is functionally superior to prevent the propagation of flammable gas when combustible gas combustion occurs in the flow path while allowing the passage of flammable gas or steam to be prevented as much as possible during normal times. Fire extinguishing performance, ability to block shock waves caused by deflagration and detonation, and shock resistance are required. Therefore, it is necessary to consider pressure loss and flame extinguishing performance in the design.

  Conventional frame arresters include mesh (wire mesh) type, crimp ribbon (corrugated plate) type, perforated plate type, etc., depending on the structure of the frame arrester element. Literature 1-6). Of these, two types, a metal mesh type and a crimp ribbon type, are practically used. The mesh type is obtained by stacking a plurality of wire meshes in order to improve the flame extinguishing performance. This is inexpensive and easy to install, but the flame extinguishing performance is limited. Since the number of wire meshes is increased to increase the flame extinguishing performance, the pressure loss also increases, so the applicable range is limited. On the other hand, in the crimp ribbon type, a corrugated sheet obtained by forming a metal thin plate into a corrugated shape is overlapped with a flat ribbon and wound in a roll shape so that a large number of cross sections in a direction perpendicular to the flow path of the combustible gas It has a structure that constitutes a triangular cell. This crimp ribbon type has the advantage that it has less pressure loss and higher flame extinguishing performance than the mesh type, so it is the current mainstream. However, the crimp ribbon type requires more man-hours than the mesh type and requires high machining accuracy. In addition, when making a large-capacity one with a large diameter, the number or number of turns must be increased. There is a problem that it becomes expensive because it does not become necessary, and the product weight also increases. Moreover, both frame arresters have a problem that clogging due to rust occurs because they are made of metal and easily rust. For this reason, it is necessary to use a metal that does not easily rust for rust prevention, or a rust prevention process for preventing rust, and it is difficult to repair when rusted.

  Patent Document 7 discloses a technique using a woven fabric using alumina fibers as a burner plate of a burner that is a heating device. By using a burner plate made of a heat-resistant fiber woven fabric, the pressure loss is small and the weaving of the weaving is less likely to occur. There is a description to get. However, the burner installed at the interface between the flammable gas and the air is intended to obtain a stable combustion state on the surface of the alumina fiber fabric, and the accident prevention in the sudden combustion accompanied by the shock wave due to the explosion of detonation and detonation The use, required performance, issues, and purpose are different from those of the frame arrester.

Japanese Utility Model Publication No. 09-1536 Japanese Patent Publication No. 56-7124 JP-A-3-274308 Japanese Patent Laid-Open No. 6-2822 JP 2005-241234 A JP 2006-349337 A JP-A-11-51329

  The above-mentioned conventional flame arrester is difficult to mold and process a very small gap for preventing the passage of flame due to deflagration and detonation, and high machining accuracy is required for production and assembly. In particular, a flame arrester for detonation requires higher flame extinguishing performance, shock wave suppression performance, and impact resistance than a flame arrester for deflagration, and is therefore required to be more complicated and highly accurate.

  In addition, the crimp ribbon type requires a great deal of labor to maintain and manage the gap between gas passage portions formed by the crimp ribbon with a certain size. Once clogging occurs at this site, disassembly and cleaning are required to restore performance, but it is difficult to create a gap of the original size during assembly.

  Therefore, an object of the present invention made in view of such a viewpoint is to use a frame arrester element made of an inorganic fiber fabric, which has a simple structure that is easy to manufacture, process and handle, is hard to be clogged, and is easy to manage. To provide a flame arrestor.

  A flame arrester according to the invention described in claim 1 for solving the above-described problem is provided in a flow path of a flammable gas, allows passage of the flammable gas by an eye formed on the inorganic fiber cloth, and allows the passage of the flammable gas. It is characterized by comprising a flame arrester element for blocking the passage of a flame generated by combustion, and an attaching means for arranging the flame arrester element so as to cross the flow path of the combustible gas.

  According to the present invention, the eyes formed on the inorganic fiber fabric allow passage of the combustible gas, and block the passage of the flame and shock wave when the combustible gas is ignited and detonation or detonation occurs. For this reason, the inorganic fiber fabric of the frame arrester element itself has a high flame extinguishing performance. The eyes formed on the inorganic fiber fabric are inevitably formed on the fabric. Therefore, the conventional flame arrester using a metal or ceramic sintered body requires complicated and advanced processing to form the gap at the gas passage part, but these are unnecessary and the number of assembly processes is small. It can be a frame arrester element that does not require high fabrication accuracy. In addition, frame arrester elements can be easily removed and replaced, and frame arresters can be easily cleaned.

  In addition, since the fiber is used as the frame arrester element, it is flexible and the inorganic fiber fabric of the present invention is not damaged even if it receives a shock wave of deflagration / detonation. The size of the formed eye does not change. Inorganic fiber fabrics do not deteriorate significantly even when exposed to flames of 1000 ° C or higher generated by deflagration / detonation. Particularly, fabrics using alumina fibers can withstand high temperatures of 2000 ° C or higher in a short time. I can do it.

  Further, since the frame arrester of the present invention is formed of an inorganic fiber fabric, unlike conventional metal frame arresters, rust does not occur due to oxidation, and clogging does not occur due to the occurrence of rust.

  Since the inorganic fiber fabric has higher flame extinguishing performance than the metal mesh, a high flame extinguishing effect can be obtained with a smaller number of sheets than the metal mesh. Furthermore, since the inorganic fiber fabric is thinner than the crimp ribbon type frame arrester element and has the same flame extinguishing performance, the frame arrester can be made compact.

  Since the processing of the inorganic fiber fabric is easy, a frame arrester having an arbitrary size and thickness can be produced without requiring complicated steps and labor. For this reason, the frame arrester of the present invention can be applied to a wide range of pipes, and a frame arrester can be easily produced according to the purpose and purpose by simply changing the type, size, and number of sheets used.

  A flame arrester according to a second aspect of the present invention is the flame arrester according to the first aspect, wherein the inorganic fiber fabric is made of at least one of alumina fiber, glass fiber, ceramic fiber, and silicon carbide fiber. According to a third aspect of the present invention, the flame arrester according to the first or second aspect is characterized in that the inorganic fiber fabric is a woven fabric.

  According to these inventions, the material and shape of the inorganic fiber fabric according to claim 1 are specifically clarified.

  According to the present invention, it is possible to obtain a frame arrester having a simple structure that is easy to manufacture, process, and handle, is not easily clogged, and is easy to manage. And, since the processing of the inorganic fiber fabric of the frame arrester element is extremely easy, it can be used for flow paths of a wide variety of sizes and sizes, just by changing the type, size, and number of sheets used of the inorganic fiber fabric of the frame arrester element. It is possible to obtain a frame arrester having various advantages such that a frame arrester adapted to various applications can be easily manufactured.

It is the figure which showed typically the flame arrestor of this invention. It is the figure which showed typically the place which arrange | positions the flame arrestor of this invention. It is a schematic diagram of the experimental apparatus of Examples 1-4 of this invention. It is a schematic diagram of the experimental apparatus of Example 5, Example 6, Comparative Example 1 and Comparative Example 2 of the present invention.

  Next, an embodiment of the present invention will be described.

  As shown in FIG. 1, the flame arrester 10 is disposed so as to intersect the flow path of the combustible gas G. The flow path of the combustible gas may have various configurations depending on the scene where the combustible gas moves. For example, a flow path for a combustible fluid, a flow path for flowing the combustible fluid from the supply device for the combustible fluid to the outside of the supply device, and a flow for supplying the supplied device to which the combustible fluid is supplied from the outside A road etc. can be considered. At this time, in consideration of the diameter of the flow channel to be arranged, the frame arrester forms the frame arrester element so that the frame arrester covers the cross section of the flow channel when arranged so as to intersect the flow channel. At this time, the frame arrester 10 of the present invention can be placed at any location in the flow path according to maintenance and safety as shown in FIG.

  Examples of the inorganic fiber cloth used as the frame arrester element 11 of the frame arrester 10 of the present invention include glass fiber cloth, alumina fiber cloth, ceramic fiber cloth, and silicon carbide fiber cloth. Among them, the alumina fiber fabric is characterized by nonflammability, high heat resistance, light weight, flexibility, high strength, no corrosion, no rust, and easy to fabricate. Can be preferably used.

  As shown in FIG. 1 described above, the inorganic fiber fabric must have a performance of blocking the passage of the flammable gas, the flame due to the detonation, and the passage of the shock wave F while allowing the flammable gas G to pass therethrough. Furthermore, it is required to have flexibility and strength to withstand shock waves, and also to have the ability to relax the energy of shock waves. Thus, examples of the shape of the inorganic fiber fabric include woven fabrics, knitted fabrics, nonwoven fabrics, laminated felt-like materials, and the like. From the viewpoints of air permeability, flexibility, shape stability, and the like, fabric fabrics are preferable. The inorganic fiber fabric is preferably made of inorganic fibers having a fiber diameter of 3 to 15 μm.

  Since knitted fabric is rich in flexibility and stretchability, it is not preferable because the opening size of the fabric fluctuates with a slight impact. However, in the case of mesh cloth made of knitted fabric, the opening size is relatively stable. Can be used. Nonwoven fabrics and felts are not preferred because they tend to generate fluff and the fluff generated from the fabric may be diffused into the system.

The opening size of the inorganic fiber fabric is preferably 1 mm ² or less. When the opening size is larger than 1 mm ^2, it is difficult to prevent the passage of the flame generated due to deflagration or detonation, and when it is 1 mm ² or less, the passage of the flame can be prevented.

  The attachment means, for example, provides a joint part for joining the frame arrester to the member constituting the flow path of the combustible gas, and arranges the frame arrester so that the flange formed on the member constituting the flow path is in contact with the frame arrester, It can be set as the structure which fixes a flange and a frame arrester. Here, the frame arrester element can be held as it is, but from the viewpoint of ease of attachment / detachment and safety, the frame arrester element is fixed by a frame-shaped support member that supports the periphery of the frame arrester element. It is preferable that the frame arrester element in a fixed state is fixed at the joint. The frame-shaped support member can be fixed, for example, by sandwiching the frame arrester element between a pair of frame-shaped support members. In the frame arrester having such a configuration, a support member holding the frame arrester element and a flange formed on the member constituting the flow path are fixed by a fixing member. Further, the combustible gas flow path may be configured using members having different diameters, and the frame arrester element may be sandwiched between the joint portions of the constituent members.

  The number of inorganic fiber fabrics used in one frame arrester in the present invention varies depending on the degree of opening of the fabric and the thickness of the fabric, but a plurality of inorganic fiber fabrics may be used. When the number of sheets is large, the performance of preventing the passage of the flame is improved, but the ventilation resistance is increased and a pressure loss is caused. Therefore, the number of sheets is increased or decreased according to the desired performance and application.

  The installation location and the installation number of the frame arrester vary depending on the specifications of the inorganic fiber fabric used as the frame arrester element, but the location to be arranged is determined according to the desired performance and application, and the number is increased or decreased. Moreover, the metal mesh for reinforcing an inorganic fiber fabric can also be used in piles. A plurality of flame arresters can be arranged in the flow path to further enhance the flame extinguishing performance and the performance of damping shock waves.

(First embodiment)
Here, the flow path is defined as an upstream side before the combustible gas moving through the flame arrester passes through the flame arrester, and a downstream side after passing through the flame arrester. As 1st Embodiment of this invention, the junction part for joining a flame arrester is provided in the edge part of piping which touches each of the upstream and downstream of a flame arrester, and it forms in the edge part of upstream piping. A frame arrester is disposed and held between the first joined portion and the second joined portion formed at the end of the downstream pipe. For the flame arrester element, the inorganic fiber fabric is cut so as to fit the diameter of the flammable gas flow path, and the fraying prevention treatment such as hardening the periphery with an inorganic resin is applied. It is fixed by a frame-shaped support member which is a component. As the inorganic resin, alumina sol or silica gel can be preferably used. In addition, the fraying prevention treatment also prevents fraying by cutting the inorganic fiber cloth by laser processing, so that the periphery of the inorganic fiber cloth is melted and fused by the heat of the laser. The first joint portion and the second joint portion include flanges, and the flange of the first joint portion, the frame that supports the frame arrester element, and the flange of the second joint portion are fixed by a fixing member. By adopting such a configuration, it is possible to easily attach / detach the frame arrester. As fixing members, for example, bolts and nuts, vise-like fasteners, fasteners applying the principle of lever, etc., which can give sufficient force to hold the frame arrester in the flow path Anything can be used.

(Second Embodiment)
In the second embodiment of the present invention, the pipes in contact with the upstream side and the downstream side of the frame arrester are formed so that the diameters of the pipes at the joint portion through the frame arrester are different from each other. The part is inserted and joined to the end of the other pipe via a frame arrester. In other words, the inner diameter of the pipe to be inserted is made larger than the outer diameter of the end of the pipe on the side to be inserted, and the side to be inserted is arranged at the end of the pipe on the side to which the frame arrester element is inserted. These pipes are joined in such a manner as to cover the pipe on the side to be inserted through the frame arrester element. The above-mentioned joining method can be used not only for pipes with different diameters, but in the case of pipes with the same diameter, only the joint part of one pipe has a shape with a larger diameter and is covered with the other pipe. You can also

  In addition, this invention is not limited to the said embodiment, A various change is possible in the range which does not deviate from the meaning of invention. In the above embodiment, the configuration in which the flame arrestor is disposed at the joint between the pipes, that is, the joints between the pipes, as the combustible gas flow path, but as described above, the flow path of the combustible gas is limited to the pipes. I can't. In other words, a flame arrester can be arranged at the joint between the combustible gas supply device and the pipe, or at the joint between the pipe and the supplied device, and at the joint between the supply device and the supplied device without using the pipe. It can also be set as the structure to arrange.

  Further, the frame arrester of the present invention does not need to consider the front and back surfaces in terms of structure. That is, since it is not necessary to consider the direction of input and output, it can be used in both directions. If it does so, it can use effectively also in the scene which needs to prevent propagation of a flame or a shock wave on both the supply side and to-be-supplied side of a combustible gas, for example.

Hereinafter, the present invention will be described with reference to examples.
FIG. 3 shows an experimental apparatus for the experiments in Examples 1 to 4 in the deflagration state. Moreover, the experimental apparatus of the experiment in the detonation state of Example 5, Example 6, Comparative Example 1, and Comparative Example 2 is shown in FIG.

  The flame arrester experiment method, experimental apparatus, and evaluation method of the results were performed in accordance with the test method of deflagration 7.3.2.2 and detonation 7.3.3.2 of ISO 16852 2008 (E).

(Experimental device)
A 1-inch steel pipe D1 (inner diameter 28.00 mm) and a 2-inch steel pipe D2 (inner diameter 56.00 mm) were used as shock wave tubes. The experiment was divided into the case of 1 inch and the case of 2 inches, and the frame arrester 10 was arranged through two flanges of the same diameter formed with flanges. Both ends of the tube are sealed, and a combustible gas supply port D4 (which can be opened and closed by a valve) and an exhaust port D5 (which can be opened and closed by a valve) are provided in the tube. An ion probe D7 for measuring the combustion wavefront passage time was attached, and this ion probe D7 was directly connected to the module of the oscilloscope. Moreover, the pressure sensor D6 for measuring a shock wave front passage time and a pressure was attached. The ignition device D3 using an electric spark plug was used for ignition of the combustible gas.

  The flame arrester 10 was installed at a position away from the ignition point of the combustible gas by a predetermined distance so as to be perpendicular to the cross section of the pipe. The pressure sensor D6 was attached upstream from the installation position of the frame arrester 10 and also downstream in the case of a detonation test. A plurality of ion probes D7 are attached to the upstream side and the downstream side of the frame arrester 10.

(Materials and production methods for frame arresters)
The inorganic fiber fabric used as the material of the frame arrester element is an alumina fiber fabric. The fabric A used for the test was 30 warps / inch using 200 tex alumina fibers, 25 wefts / inch twill, and fabric B was 40 warps / inch using 400 tex alumina fibers, 18 wefts / inch. Is a double woven fabric. Cut the alumina fiber fabric to an area larger than the cross-sectional area of the steel pipe, apply alumina sol to the periphery to prevent fraying of the cut surface, dry it, and sandwich it between packings coated with vacuum grease and install it at the joint of the pipe did.

(Combustible gas mixture)
In this experiment, a hydrogen-air mixed gas was used.

(experimental method)
(1) The entire inside of the steel pipe is sucked with a vacuum pump to be almost in a vacuum state. At that time, the pressure inside the steel pipe is recorded.
(2) A combustible gas mixture is supplied to the entire tube, and the gas mixture is filled until the inside of the tube reaches atmospheric pressure.
(3) Ignition by electric spark. Record the pressure in the tube and the arrival time of the shock wave after the explosion. At the same time, the arrival time of the combustion wave is measured and recorded by the ion probe.

(Evaluation analysis)
When the combustible gas is ignited at one end of the tube, a shock wave or a combustion wave propagates toward the other end. Since the arrival time of the combustion wave is detected by the ion probe, if the combustion wave is detected by the ion probe downstream of the flame arrester, it means that the combustion wave has passed through the flame arrester, causing detonation or detonation. This means that the passage of the resulting flame could not be prevented. From the pressure in the pipe measured by the pressure sensor, it can be determined whether the combustible gas in the pipe has burned completely or remains without burning. If flammable gas remains, it means that the flame has been extinguished by the flame arrester. Further, since the propagation speed of the shock wave can be detected, it is possible to determine whether the combustion state is a deflagration or detonation state.

Example 1
In Example 1, an experiment was conducted to determine whether flames and shock waves generated due to deflagration pass through the flame arrestor. The experimental apparatus is shown in FIG. A 1-inch tube (inner diameter: 28.00 mm) and a steel tube having a length of 1 m were used as the shock wave tube. As a flame arrester element, the alumina fiber fabric A was cut into a circle having a diameter of 30 mm, and in order to prevent fraying, alumina sol was applied to the periphery of the circle and dried well. This alumina fiber fabric was attached to the joint portion of the pipe as a frame arrester 10 by sandwiching it between packings well coated with vacuum grease. The mounting position of the flame arrester is 40 cm away from the gas ignition position. After the air inside the tube was removed by suction with a vacuum pump, a mixed gas of 45% hydrogen gas and 55% air was filled from the combustible gas supply port D4 until the pressure in the tube reached atmospheric pressure (1009.3 hPa). When the combustible gas was ignited by the ignition device D3, the ion probe installed between the ignition point and the flame arrester detected the passage of the combustion wave, but the ion probe installed downstream of the flame arrester detected the passage of the combustion wave. I did not. That is, it was confirmed that the flame arrester prevented the passage of the flame. In addition, the shock wave attenuation was confirmed from the pressure waveform of the shock wave downstream of the flame arrestor. From these results, it was confirmed that it was effective in preventing flames and shock waves caused by deflagration.

(Example 2)
Also in Example 2, an experiment in a deflagration state was performed. A combustion experiment was conducted in the same manner as in Example 1 except that the alumina arrester element A was replaced with the alumina fiber cloth A and one alumina fiber cloth B was used. The experimental apparatus having the configuration shown in FIG. As a result, the ion probe installed between the ignition point and the flame arrestor detected the passage of the combustion wave, but the ion probe installed downstream of the flame arrester did not detect the passage of the combustion wave. It was confirmed that the passage was blocked. No breakage of the alumina fiber fabric was observed. In addition, the shock wave attenuation was confirmed from the pressure waveform of the shock wave downstream of the flame arrestor. From these results, it was confirmed that it was effective in preventing flames and shock waves caused by deflagration.

(Example 3)
Also in Example 3, an experiment in a deflagration state was performed. The experimental apparatus is shown in FIG. A 2 inch (inner diameter 56.00 mm), 2 m long steel tube was used as the shock wave tube. Alumina fiber fabric A as a frame arrester element was cut into a circle having a diameter of 60 mm, and the same processing as in Example 1 was performed and sandwiched between packings, and attached as a frame arrester 10 to a steel pipe joint. The mounting position is 1 m from the ignition point of the combustible gas. Two ion probes were installed on the upstream side of the frame arrester and one on the downstream side. A gas mixture of 45% hydrogen gas and 55% air was ignited by an electric spark and burned. As a result, the two ion probes on the upstream side of the flame arrester detected the passage of the combustion wave, but the downstream ion probe did not detect it, confirming that the flame arrester blocked the passage of the flame. It was. No breakage of the alumina fiber fabric was observed. In addition, the shock wave attenuation was confirmed from the pressure waveform of the shock wave downstream of the flame arrestor. From these results, it was confirmed that it was effective in preventing flames and shock waves caused by deflagration.

Example 4
Also in Example 4, an experiment in a deflagration state was performed. A combustion experiment was conducted in the same manner as in Example 3 except that the alumina fiber fabric A of the flame arrester element was replaced with the alumina fiber fabric B. The experimental apparatus having the configuration shown in FIG. As a result of the experiment, the two ion probes upstream of the flame arrester detected the passage of the combustion wave, but the downstream ion probe did not detect, confirming that the flame arrester blocked the passage of the flame. did it. No breakage of the alumina fiber fabric was observed. In addition, the shock wave attenuation was confirmed from the pressure waveform of the shock wave downstream of the flame arrestor. From these results, it was confirmed that it was effective in preventing flames and shock waves caused by deflagration.

(Example 5)
In Example 5, an experiment was conducted to determine whether flames and shock waves generated due to detonation pass through the flame arrestor. The experimental apparatus is shown in FIG. As the shock wave tube, a 1 inch (inner diameter 28.00 mm), 7 m long steel tube was used. In order to make the combustion wave detonate, a 40 cm long wire bent in a spiral shape was attached in the tube at the ignition point. The combustible gas is a mixed gas of 45% hydrogen gas and 55% air.

  The first flame arrester in which two alumina fiber fabrics B were stacked as a flame arrester element was installed at a position 3 m away from the ignition point. Further, a second frame arrester in which two alumina fiber fabrics B were stacked as a frame arrester element was installed in the pipe with a spacing of 50 cm downstream from the first. One pressure sensor was installed on the upstream side of the first frame arrester, two between the first frame arrester and the second frame arrester, and one on the downstream side of the second frame arrester. Five ion probes were attached upstream of the first frame arrester, one between the first frame arrester and the second frame arrester, and three downstream of the second frame arrester.

  When ignited with an electric spark, the alumina fiber fabric of the first frame arrester was damaged, but the alumina fiber fabric of the second frame arrester was not damaged, and the ion attached downstream of the second frame arrester. Since no combustion wave was detected by the probe, it was confirmed that the second flame arrester blocked the passage of the flame. Regarding the shock wave, the first frame arrester was damaged, but it was confirmed that the pressure waveform showed a value of 0 on the downstream side of the second frame arrester. That is, the first frame arrester is damaged, but the energy of the shock wave is absorbed, and the second frame arrester is considered to completely block the shock wave. From these results, it was confirmed that the flame and shock wave caused by detonation can be effectively prevented by using a plurality of flame arresters.

(Example 6)
Also in Example 6, an experiment in a detonated state was conducted. The same experiment as in Example 5 was performed except that the distance between the two frame arresters was set to 1 cm. As in the case of Example 5, the experimental apparatus having the configuration shown in FIG. 4A was used except that the interval between the two frame arresters was 1 cm. As a result, the alumina fiber fabric of the first frame arrester was damaged, but the alumina fiber fabric of the second frame arrester was not damaged, and the ion probe attached downstream of the second frame arrester burned. Since no wave was detected, it was confirmed that the second flame arrester blocked the passage of the flame. Regarding the shock wave, the first frame arrester was damaged, but it was confirmed that the pressure waveform showed a value of 0 on the downstream side of the second frame arrester. That is, the first frame arrester is damaged, but the energy of the shock wave is absorbed, and the second frame arrester is considered to completely block the shock wave. From these results, it was confirmed that the flame and shock wave caused by detonation can be effectively prevented by using a plurality of flame arresters.

(Comparative Example 1)
Also in Comparative Example 1, an experiment in a detonated state was conducted. An experiment was conducted to determine whether shock waves and flames caused by detonation pass through the flame arrestor. The experimental apparatus is shown in FIG. As the shock wave tube, a 1 inch (inner diameter 28.00 mm), 7 m long steel tube was used. In order to make the combustion wave detonate, a 40 cm long wire bent in a spiral shape was attached in the tube at the ignition point. One frame arrester in which two alumina fiber fabrics A were stacked as a frame arrester element was installed at a position 3 m away from the ignition point. Pressure sensors were installed at one upstream side and one downstream side of the flame arrester. Five ion probes were attached upstream of the frame arrester and three on the downstream side. The combustible gas is a mixed gas of 45% hydrogen gas and 55% air. When the combustible gas was ignited with an electric spark, the alumina fiber fabric was confirmed to be damaged. This is considered to be because the shock wave generated due to detonation was too strong, and the energy of the shock wave could not be absorbed by one frame arrester, and the thickness of the alumina fiber fabric was thin.

(Comparative Example 2)
Also in Comparative Example 2, an experiment in a detonated state was performed. As in the first comparative example, the experimental apparatus having the configuration shown in FIG. An experiment similar to Comparative Example 1 was conducted except that the flame arrester element was replaced with the alumina fiber fabric A and the two alumina fiber fabrics B were stacked. As a result, damage to the alumina fiber fabric was confirmed. It is considered that the shock wave was too strong even when the two alumina fiber fabrics B were stacked, and the energy of the shock wave could not be sufficiently absorbed by one frame arrester.

  The flame arrester of the present invention selects and processes the flame arrester element according to the application and purpose, so that only the flow path of the plant that handles flammable fluid such as chemical factory, storage equipment, power plant, gas well, oil well, etc. Not only flammable fluid storage facilities / equipment, fuel cells, automobiles, hot water supply facilities, dryers, etc., but also flame propagation and shock wave equipment when combustion occurs due to ignition in various flow paths that handle flammable fluids It can be used as a device that prevents accidents such as the occurrence of secondary disasters accompanying damage to equipment and equipment.

10 ... Flame arrestor 11 ... Flame arrestor element 12 ... Frame arrester element support member F ... Flame and shock wave G ... Flammable fluid P ... Pipe A ... Flammable fluid supply equipment B ... Flammable fluid cover Supply equipment D1 ... 1 inch steel pipe D2 ... 2 inch steel pipe D3 ... Ignition device D4 ... Flammable gas supply port D5 ... Flammable gas exhaust port D6 ... Pressure sensor D7 ... Ion probe D8 ... Detonation Generating wire

Claims (3)

A flame arrestor element that is provided in the flow path of the combustible gas and that allows passage of the combustible gas by the eyes formed in the inorganic fiber cloth and prevents the passage of the flame generated by the combustion of the combustible gas;
Mounting means for disposing the flame arrestor element across the flow path of the combustible gas;
A frame arrester characterized by comprising:   The flame arrester according to claim 1, wherein the inorganic fiber fabric is made of at least one of alumina fiber, glass fiber, ceramic fiber, and silicon carbide fiber.   The frame arrester according to claim 1, wherein the inorganic fiber fabric is a woven fabric.