CN117797428A

CN117797428A - Fire-resistant flame arrester of pipe end

Info

Publication number: CN117797428A
Application number: CN202211212952.0A
Authority: CN
Inventors: 鲍磊; 王鹏; 刘阳昊; 陈国鑫; 于安峰; 顾蒙; 王浩喆
Original assignee: Sinopec National Petrochemical Project Risk Assessment Technology Center Co ltd; China Petroleum and Chemical Corp; Sinopec Safety Engineering Research Institute Co Ltd
Current assignee: Sinopec National Petrochemical Project Risk Assessment Technology Center Co ltd; China Petroleum and Chemical Corp; Sinopec Safety Engineering Research Institute Co Ltd
Priority date: 2022-09-30
Filing date: 2022-09-30
Publication date: 2024-04-02

Abstract

The invention provides a pipe end burning-resistant flame arrester, which comprises: the lower end of the first connecting cavity forms a connecting flange; a firestop unit installed at an upper port of the first connection chamber; the second connecting cavity is connected to the upper end of the first connecting cavity; and a burn-resistant unit mounted at an upper port of the second connection cavity; the effective flow area of the fire-resistant unit is larger than that of the connecting flange and smaller than that of the fire-retardant unit, and a heat-insulating cavity between the fire-resistant unit and the fire-retardant unit is formed in the second connecting cavity.

Description

Fire-resistant flame arrester of pipe end

Technical Field

The invention belongs to the technical field of flame arresters, and particularly relates to a pipe end burning-resistant flame arrestor.

Background

In the process of feeding and discharging the petrochemical device storage tank or when the external temperature rises, the gas phase pressure in the tank rises, and in order to prevent the storage tank from being damaged by overpressure or from being blocked, a breather valve is generally arranged at the top of the tank. When an ignition source exists outside, the combustible gas exhaled by the storage tank can be ignited, so that flame is transmitted back to the storage tank to cause fire or explosion of the storage tank. For this reason, the breather valve needs to have a fire-blocking function. API2000 suggests that for a tank with a gas phase space of 1 zone after setting up a nitrogen seal (or other gas seal), the breather valve flame arrestor should be a long-time flame-resistant atmospheric flame arrestor with a flame resistance time of not less than 2 hours. All-weather fire-retarding breather valve should be selected from products subjected to integral fire-retarding test.

There are still problems with existing flame arresters, such as flame failure of the flame arrestor caused by the flame passing directly through the flame arrestor after the combustible gas is ignited by an external fire source. When the flame retardant is burnt for a long time, most of combustible gas exhaled by the storage tank is premixed combustible gas, the combustion heat value is high, the combustible gas is concentrated on the surface of the flame retardant plate to burn, and heat is quickly accumulated on the combustion side to lead to heat conduction to the protection side to cause tempering, so that the combustion heat can easily penetrate the flame retardant plate. Especially after suddenly stopping gas, the fire-retardant plate can accelerate the transfer to the device in the state that does not have gas to sweep, and then will block up the internal combustible gas of firearm and fire, leads to resistant fever function to lose, not only influences the normal work of breather valve, has the potential safety hazard moreover.

Disclosure of Invention

Aiming at the technical problems, the invention aims to provide the pipe end burning-resistant flame arrester, which can effectively reduce the accumulation of burning heat on the surface, reduce the conduction of flame heat and is very beneficial to improving the long-term burning resistance of the pipe end burning-resistant flame arrester.

To this end, according to the invention there is provided a tube end fire arrestor comprising: the lower end of the first connecting cavity forms a connecting flange; a firestop unit installed at an upper port of the first connection chamber; the second connecting cavity is connected to the upper end of the first connecting cavity; and a burn-resistant unit mounted at an upper port of the second connection cavity; the effective flow area of the fire-resistant unit is larger than that of the connecting flange and smaller than that of the fire-retardant unit, and a heat-insulating cavity between the fire-resistant unit and the fire-retardant unit is formed in the second connecting cavity.

In one embodiment, the effective flow area of the fire-resistant unit is smaller than the effective flow area of the fire-resistant unit by adjusting the average characteristic size h, the cross-sectional area S, and the number of flow-through pores of the fire-resistant unit and the fire-resistant unit.

In one embodiment, the burn-resistant unit is provided with a flow-through adjustment mechanism configured to automatically expand when the burn-resistant unit burns outside and reaches a predetermined temperature to block the flow area of the burn-resistant unit, thereby reducing the effective flow area of the burn-resistant unit such that the effective flow area of the burn-resistant unit is less than the effective flow area of the firestop unit.

In one embodiment, the circulation regulating mechanism is arranged at the upper end of the burn-resistant unit, the circulation regulating mechanism is made of temperature memory alloy and comprises a plurality of regulating plates which are uniformly distributed at intervals, and the preset temperature is not lower than 80 ℃.

In one embodiment, the flow-through regulating mechanism is configured to include at least two flaps of a baffle plate and a fusible link unit for defining the baffle plate, the baffle plate being disposed at a lower end of the burn-resistant unit, the fusible link unit extending through the burn-resistant unit and upward,

the fusible link unit is configured to initially define the flaps of the barrier overlap and to fuse when the predetermined temperature is reached to cause the flaps of the barrier to automatically open.

In one embodiment, the thermally insulating cavity is filled with a low thermal conductivity gas or material.

In one embodiment, the second connection cavity is provided with a heat dissipation mechanism.

In one embodiment, the heat dissipation mechanism adopts a heat pipe, a heated section of the heat pipe is positioned inside the second connection cavity, and a heat release end is positioned outside the second connection cavity.

In one embodiment, the first connection cavity is configured to include a bell-mouth-shaped body having a diameter increasing from bottom to top and a connection cylinder for connecting the connection flange.

In one embodiment, a first support is provided at the upper port of the bell-mouth shaped body for mounting the firestop unit.

In one embodiment, a second support is provided at the upper port of the second connection cavity for mounting the burn-resistant unit.

In one embodiment, the first connection cavity and the second connection cavity form a fixed connection through a connection unit, and the connection unit comprises a fastener and a sealing gasket.

In one embodiment, a rain-proof cover is arranged above the burn-resistant unit, the rain-proof cover is limited by a fusible connecting piece, the fusible connecting piece can be fused when burning occurs outside the burn-resistant unit and reaches a preset temperature, and the rain-proof cover can be automatically sprung out after the fusible connecting piece is fused.

Compared with the prior art, the application has the advantages that:

according to the pipe end fire-resistant flame arrester, the effective flow area of the fire-resistant unit is smaller than that of the fire-resistant unit, so that the combustible gas has high flow rate when being discharged out of the fire-resistant unit, the flame surface height is further improved, and the accumulation of heat on the surface of the fire-resistant unit is obviously reduced. Meanwhile, the fire-resistant units are distributed above the fire-retardant units at intervals, so that a heat-insulating cavity between the fire-resistant units and the fire-retardant units is formed in the second connecting cavity, heat transfer of the fire-resistant units is further reduced by the heat-insulating cavity, and the fire-resistant flame arrester at the pipe end can be effectively guaranteed to have long-term fire-resistant performance. The fire-retarding unit has larger heat conduction area, so that the dissipation of external heat on the side of the fire-retarding unit is further quickened, and the heat is prevented from being conducted to the inner part. In addition, the horn-shaped structural design of the first connecting cavity and the second connecting cavity enables the exhaled combustible gas to have the cooling effect on the burning-resistant unit, and the burning resistance of the pipe-end burning-resistant flame arrester is further improved.

Drawings

The present invention will be described below with reference to the accompanying drawings.

Fig. 1 schematically shows the structure of a tube-end fire-resistant flame arrester according to the present invention.

Fig. 2 schematically shows the structure of the tube-end fire-resistant flame arrester in example 2.

Fig. 3 schematically shows the structure of the tube-end fire-resistant flame arrester in example 3.

Fig. 4 schematically shows the structure of the tube-end fire-resistant flame arrester in example 4.

Fig. 5 schematically shows the structure of the tube-end fire-resistant flame arrester in example 5.

Fig. 6 schematically shows the structure of the tube-end fire-resistant flame arrester in example 6.

Fig. 6a schematically illustrates the configuration of the flow-through adjustment mechanism in the tube-end fire-resistant flame arrestor of fig. 6.

Fig. 6b and 6c schematically show the flow-through adjustment mechanism of fig. 6a in a contracted state and in an expanded state, respectively.

Fig. 7 schematically shows the structure of the tube-end fire-resistant flame arrester in example 7.

Fig. 7a schematically illustrates the flow control mechanism of the tube end fire arrestor of fig. 7 with the baffle in a folded configuration.

Fig. 7b schematically illustrates the flow regulating mechanism of the tube end fire arrestor of fig. 7 in its deployed configuration.

Fig. 8 schematically shows the structure of the tube-end fire-resistant flame arrester in example 8.

In this application, all of the figures are schematic drawings which are intended to illustrate the principles of the invention and are not to scale.

Detailed Description

The invention is described below with reference to the accompanying drawings.

In this application, it should be noted that the directional terms or qualifiers "upper", "lower", etc. used in this application are used for the purpose of describing the present invention and simplifying the description only, and do not indicate or imply that the apparatus or element in question must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as limiting the invention.

Fig. 1 shows the structure of a tube-end fire-resistant flame arrester 100 according to the present invention. As shown in fig. 1, the tube-end fire-resistant flame arrester 100 includes a first connection chamber 2, a fire-resistant unit 4, a second connection chamber 5, and a fire-resistant unit 7. The lower end of the first connecting cavity 2 forms a connecting flange 1 for connection with the main body pipeline of the storage tank. The firestop unit 4 is installed at the upper port of the first connection chamber 2. The second connecting cavity 5 is connected to the upper end of the first connecting cavity 2, and the burn-resistant unit 7 is installed at the upper port of the second connecting cavity 5. The effective flow area of the fire-resistant unit 7 is set to be larger than the flow area of the connecting flange 1 and smaller than the effective flow area of the fire-retardant unit 4, so that the combustible gas has higher flow velocity when being discharged out of the fire-resistant unit 7, the height of a flame surface is further improved, and the accumulation of heat on the surface of the fire-resistant unit 7 is reduced. Meanwhile, the fire-resistant units 7 are spaced apart above the firestop units 4, thereby forming a heat-insulating cavity between the fire-resistant units 7 and the firestop units 4 inside the second connection cavity 5. The heat-insulating cavity can further reduce the heat transfer of the burn-resistant unit 7, so that the pipe-end burn-resistant flame arrester 100 can be effectively ensured to have long-term burn-resistant performance.

As shown in fig. 1, the first connection chamber 2 is configured to include a bell-mouth-shaped body 21 having a diameter increasing from bottom to top and a connection cylinder 22 for connection with the connection flange 1. Preferably, the bell-mouth-shaped body 21, the connecting cylinder 22, and the connecting flange 1 are constructed as one piece.

At the upper port of the bell-mouth shaped body 21 is provided a first support 3, the first support 3 being for mounting the firestop unit 4. In one embodiment, the upper port of the bell-mouth shaped body 21 is configured as a cylindrical mounting portion, and the first support 3 is fixed to an inner wall of the cylindrical mounting portion. The firestop unit 4 is mounted in the cylindrical mounting portion and is supported by the first support 3. This kind of structure of first connection cavity 2 is convenient for not only realize the dismantlement and the installation of fire retardant unit 4, can effectively guarantee the installation stability of fire retardant unit 4 moreover.

As shown in fig. 1, a second support member 6 is provided at the upper port of the second connection cavity 5, and the second support member 6 is used for mounting a burn-resistant unit 7. Preferably, the second support 6 is configured as a support plate arranged on the inner wall of the upper port of the second connection chamber 5 and extending radially inwards. The burn-resistant unit 7 is mounted on the second support 6. The structure of the second connecting cavity 5 is not only convenient for realizing the disassembly and the installation of the burn-resistant unit 7, but also can effectively ensure the installation stability of the burn-resistant unit 7.

According to the invention, as shown in fig. 1, the first connection chamber 2 and the second connection chamber 5 form a fixed connection by means of a connection unit 8, the connection unit 8 comprising a fastener and a sealing gasket. For example, the upper end of the first connecting chamber 2 and the lower end of the second connecting chamber 5 are provided with butt flanges capable of being butted, and a sealing gasket is installed between the two butt flanges. The first connecting cavity 2 and the second connecting cavity 5 form fixed connection through a fastener, and the sealing gasket is pressed tightly, so that the connection between the two is ensured to be leak-free. In order to reduce the conduction of heat from the second connecting chamber 5 to the first connecting chamber 3, the sealing gasket is preferably a gasket with a low thermal conductivity.

According to one embodiment of the invention, as shown in fig. 1, a rain cover 10 may be provided above the burn-resistant unit 7. One side of the rain cover 10 is connected with the butt flange of the second connecting cavity 5 through a reset mechanism, which may be a torsion spring or other structure. At the same time, the rain shield 10 is defined by the fusible link 9. For example, one end of the fusible link 9 is fixed to the center of the burn-resistant unit 7, and the other end is fixedly connected to the rain cover 10. Thus, in the initial state, the fusible link 9 defines the rain cover 10 such that the rain cover 10 remains directly above the burn-resistant unit 7. Thus, the pipe end fire-resistant flame arrester 100 is rainproof, and the pipe end fire-resistant flame arrester 100 is prevented from being blocked due to nesting of birds and the like. When the outside of the burn-resistant unit 7 burns and reaches a predetermined temperature, the fusible connecting piece 9 can be fused, and at the moment, the rain cover 10 can automatically spring open to one side of the pipe end burn-resistant flame arrester 100 under the action of the reset mechanism so as to separate from the combustion side, so that the combustion flame on the outside of the burn-resistant unit 7 is communicated with the outside atmosphere, and the accumulation of flame heat on the combustion side is avoided.

According to the invention, the fire-retarding unit 4 adopts a porous structure, and the average characteristic dimension h of the pores of the fire-retarding unit 4 ₁ According to the setting of the fire-retardant medium, h ₁ Is smaller than the MESG value (maximum experimental safety gap) of the corresponding combustible gas medium. Preferably, h ₁ And not more than 0.85 times the MESG value corresponding to the combustible gas medium. At the same time, it is ensured that the number of pores above the MESG value does not exceed 10%, preferably 5%, of the total number of pores. The cross-sectional area of the firestop unit 4 is S ₁ Porosity is delta ₁ An effective flow area of S _{1 has} ＝S ₁ *δ ₁ ，S ₁ *δ ₁ ＞S ₀ Preferably S ₁ *δ ₁ ＞1.5S ₀ . Axial thickness L of fire-retardant unit 4 ₁ Depending on the fire-retardant and burn-resistant medium, this will vary. L (L) ₁ More than or equal to 10mm, preferably, the relation quantification can be carried out with the MESG value of the corresponding combustion medium, and the L is satisfied ₁ And the unit is not less than 10/MESG medium.

For a common flame arrestor rating, corresponding to a typical flammable gas MESG value (maximum experimental safety gap), the following thicknesses may also be given:

fire-retardant grade	IIA	IIB3	IIC
				Representing a gas	Propane	Ethylene	Hydrogen gas
Gas MESG value	0.95mm	0.67mm	0.31mm
				Lower limit of the thickness of the fire-retardant unit	10mm	15mm	33mm

The burn-resistant unit 7 also adopts a porous structure according to the present invention. The effective flow area of the fire-resistant unit 7 is smaller than the effective flow area of the fire-retardant unit 4 and slightly larger than the flow area of the connecting flange 1, i.e. S ₀ ＜S _{2 have} ≤S _{1 has} Preferably S ₀ ＜S _{2 have} ≤0.85S _{1 has} 。

According to one embodiment of the present invention, the effective flow area of the fire-resistant unit 7 is smaller than the effective flow area of the fire-resistant unit 4 by adjusting the corresponding parameter relationship of the fire-resistant unit 4 and the fire-resistant unit 7, such as the average characteristic dimension h of the pores, the cross-sectional area S, and the number of flow-through pores.

For example, the cross-sectional area of the burn-resistant unit 7 and the cross-sectional area of the firestop unit 4 may be set to be equal, while the average pore characteristic size of the burn-resistant unit 7 is smaller than the average pore characteristic size of the firestop unit 4, i.e., S ₁ ＝S ₂ ，h ₂ ＜h ₁ Preferably h ₂ ≤0.5h ₁ . Thereby, an effective flow area S of the burn-resistant unit 7 is achieved _{2 have} Less than the effective flow area S of the fire-retarding unit 4 _{1 has} 。

Or, for example, the pore average characteristic size of the fire resistant unit 7 and the pore average characteristic size of the fire retardant unit 4 may be set to be equal while the cross-sectional area of the fire resistant unit 7 is smaller than the cross-sectional area of the fire retardant unit 4, i.e., h ₂ ＝h ₂ ，S ₂ ＜S ₁ Preferably S ₂ ≤0.85S ₁ . Thereby, an effective flow area S of the burn-resistant unit 7 is achieved _{2 have} Less than the effective flow area S of the fire-retarding unit 4 _{1 has} 。

Or for example, the average characteristic size and the cross-sectional area of the fire-resistant unit 7 may be adjusted simultaneously so that the average characteristic size of the pores of the fire-resistant unit 7 is smaller than the average characteristic size of the pores of the fire-retardant unit 4, and the cross-sectional area of the fire-resistant unit 7 is smaller than the cross-sectional area of the fire-retardant unit 4, i.e., h ₂ ＜h ₁ ，S ₂ ＜S ₁ . Thereby, an effective flow area S of the burn-resistant unit 7 is achieved _{2 have} Less than the effective flow area S of the fire-retarding unit 4 _{1 has} 。

Also for example, the number of flow-through apertures of the burn-resistant unit 7 may be adjusted such that the effective flow area S of the burn-resistant unit 7 _{2 have} Less than the effective flow area S of the fire-retarding unit 4 _{1 has} 。

According to another embodiment of the invention, the burn-resistant unit 7 may be provided with a flow-through adjustment mechanism 11. The flow-through regulating mechanism 11 is configured to automatically expand when the outside of the burn-resistant unit 7 burns and reaches a predetermined temperature to block the flow area of the burn-resistant unit 7, thereby reducingThe effective flow area of the fire resistant unit 7 is such that the effective flow area of the fire resistant unit 7 is smaller than the effective flow area of the fire retardant unit 3. Thereby, an effective flow area S of the burn-resistant unit 7 is achieved _{2 have} Less than the effective flow area S of the fire-retarding unit 4 _{1 has} 。

As shown in fig. 6, a circulation regulating mechanism 11 may be provided at the upper end of the burn-resistant unit 7, and the circulation regulating mechanism 11 is made of a temperature memory alloy including a plurality of regulating plates 111 uniformly spaced apart and distributed, and the predetermined temperature is not lower than 80 ℃, preferably above 120 ℃. Initially, the adjustment plates 111 contract, and the gaps between adjacent adjustment plates 111 are larger, so that the effective flow area of the burn-resistant unit 7 is larger. When combustion occurs at the outer side of the combustion-resistant unit 7, the adjusting plate 111 made of the temperature memory alloy is unfolded when the temperature reaches a preset high temperature, so that the flow area of the combustion-resistant unit 7 is sealed by the adjusting plate 111 more, the effective flow area of the combustion-resistant unit 7 is further reduced, the air flow speed is accelerated, and the flame height is effectively raised.

As shown in fig. 7, the flow-through adjusting mechanism 110 may be further configured to include at least two flaps 121 and a fusible link unit 122 for defining the flaps 121, the flaps 121 being disposed at a lower end of the burn-resistant unit 7, and the fusible link unit 122 penetrating through the burn-resistant unit 7 and extending upward. The fusible link unit 122 is configured to initially define a plurality of flaps of the barrier 121 to overlap and to fuse when a predetermined temperature is reached to automatically open the plurality of flaps of the barrier 121, thereby reducing the effective flow area of the burn-in resistant unit 7, accelerating the air flow speed, and effectively elevating the flame height. Preferably, when the rain cover 10 is provided, the fusible link unit 122 is formed integrally with the fusible link 9.

According to the invention, the second connection chamber 5 (i.e. the insulating cavity) is filled with a low thermal conductivity gas or with a low thermal conductivity material. The low thermal conductivity gas may be, for example, air. The low thermal conductivity material may be, for example, a low thermal conductivity ceramic or other material having good thermal insulation properties. When the combustion occurs at the outer side of the combustion-resistant unit 7, air or low heat conduction material filled in the second connecting cavity 5 is used as a heat conduction carrier, so that the heat conduction rate is reduced, the heat transfer from the combustion-resistant unit 7 to the fire retarding unit 4 can be effectively reduced, and the pipe end combustion-resistant flame arrester 100 can be ensured to have long-term combustion-resistant performance.

Of course, in an embodiment not shown, a heat insulating element with low heat conductivity can also be arranged in the second connection chamber 5. Preferably, the heat insulating element can adopt a structural design with a small heat contact surface so that the heat conduction is small, for example, the heat insulating element can be in line contact with the fire resisting unit 7 and the fire retarding unit 4, so that the heat conduction contact area is reduced, and the heat resistance is increased. For example, the insulating element may employ a wire having a diameter of 2mm as the insulating medium.

In one embodiment, as shown in fig. 8, a heat dissipation mechanism 13 may be further provided in the second connection cavity 7. The heat dissipation mechanism 13 may be, for example, a heat pipe, and a heated section of the heat pipe is located inside the second connection cavity 7, and a heat dissipation end is located outside the second connection cavity 7. When combustion occurs outside the burn-resistant unit 7, the heat dissipation mechanism 13 can further reduce the heat transfer of the burn-resistant unit 7 to the firestop unit 4.

In practical application, under normal circulation working conditions, the gas medium sequentially passes through the connecting flange 1, the first connecting cavity 2, the fire retarding unit 4, the second connecting cavity 5 and the fire retarding unit 7 during normal gas circulation, and the effective circulation areas of the fire retarding unit 4 and the fire retarding unit 7 are larger than the circulation area of the connecting pipeline, so that the resistance of gas circulation is not increased additionally.

Under the fire-retardant working condition, the combustible gas medium sequentially passes through the connecting flange 1, the first connecting cavity 2, the fire-retardant unit 4, the second connecting cavity 5 and the fire-retardant unit 7 to spread to the atmosphere, and when the fire-retardant unit encounters lightning or other possible ignition sources, combustion occurs, and external combustion flame cannot spread reversely under the fire-retardant effect of the fire-retardant unit 7. Even if the fire-retarding unit 7 fails in retarding fire, the fire-retarding unit 4 can realize secondary fire retarding to ensure the fire retarding function of the pipe end fire retarding type fire retarding device 100.

Under the long-time burning-resistant working condition, the combustible gas medium continuously passes through the connecting flange 1, the first connecting cavity 2, the fire retarding unit 4, the second connecting cavity 5 and the burning-resistant unit 7 to spread to the atmosphere in sequence, and is burnt when encountering lightning strokes or other possible ignition sources. On the one hand, because the effective flow area of the fire resisting unit 7 is smaller than that of the fire retardant unit 4, the speed of the combustible gas discharged through the fire resisting unit 7 is increased, and then the combustion surface of the fire resisting unit 7 is lifted, so that heat accumulation on the surface of the fire resisting unit 7 is avoided, and heat on the combustion side is accelerated to be taken away by outside ventilation air. On the other hand, the heat-insulating cavity partition between the fire-resistant unit 7 and the fire-retardant unit 4 through low heat conductivity reduces the heat propagation to the fire-retardant unit 4 caused by heat accumulation of the fire-resistant unit 7 due to long-term combustion, and meanwhile, the effective flow area of the fire-retardant unit 4 is larger than that of the fire-resistant unit 7, so that the heat from the fire-resistant unit 7 is quickly dissipated by the fire-retardant unit 4, and further, the combustible gas in a igniting device or a pipeline caused by overhigh temperature of the fire-retardant unit 4 is avoided, and the long-term fire-resistant function is realized.

The pipe end fire-resistant flame arrester 100 according to the present invention is provided with at least one fire-resistant unit 4 and at least one fire-resistant unit 7, and the fire-resistant unit 4 is disposed apart from the fire-resistant unit 7.

Of course, the tube-end fire-resistant flame arrester 100 of the present invention can also be applied to fire-resistant respiratory valves and long-time fire-resistant respiratory valves.

The tube-end burn-resistant flame arrester 100 according to the present invention is described in detail below in various embodiments.

Example 1

The pipe end fire-resistant flame arrester 100 takes the type IIA as an example of the explosion-proof grade, and the specification of the flame arrester is DN100. The test uses a propane air mixture. Wherein the propane MESG value was 0.95mm.

As shown in fig. 1, the specification of the connection flange 1 is DN100. The horn-shaped first connecting chamber 2 has a lower dimension DN100 and an upper dimension DN200. The firestop unit 4 had a diameter of 200mm. The second connecting chamber 5 is constructed in a bell-mouth-shaped structure with a diameter decreasing from bottom to top.

The fire-retarding unit 4 adopts a corrugated plate fire-retarding plate, the center of which is a through hole due to processing and the like, and in this embodiment, the central hole of the corrugated plate fire-retarding plate is plugged to prevent flames or combustible gas from passing through. Average characteristic dimension h of pores of fire-retardant unit 4 ₁ 0.8mm and a porosity of 0.65. Thickness L in axial direction ₁ Is 10mm.

The lower part of the second connecting cavity 5 is connected with the fire-retarding unit 4, the lower part size of the fire-retarding unit is DN200, the upper part of the second connecting cavity 5 is matched with the second supporting piece 6 to place the fire-retarding unit 7, and the upper part size of the fire-retarding unit is DN150. The diameter of the burn-resistant unit 7 is 150mm.

The fire-resistant unit 7 adopts a corrugated plate fire-retardant plate as well, and the average characteristic dimension h of the pore space ₂ 0.45mm and a porosity of 0.55. Thickness L in axial direction ₂ Is 10mm.

Thus, by making the cross-sectional area of the burn-resistant unit 7 smaller than that of the firestop unit 4, i.e., S ₂ ＜S ₁ The average characteristic dimension of the pores of the fire-resistant unit 7 is smaller than that of the fire-retardant unit 4, namely h ₂ ＜h ₁ Thereby realizing the effective flow area S of the burn-resistant unit 7 _{2 have} Less than the effective flow area S of the fire-retarding unit 4 _{1 has} 。

In addition, in order to prevent rain and bird nesting from causing the pipe end fire arrestor 100 to clog, a rain cover 10 may be attached over the fire resistant unit 7 by a fusible link 9.

Compared with the conventional common flame retardant (comparative example 1), the flame retardant has the specification of DN100 and the flame retardant grade of IIA. The fire-retarding units are the same as the fire-retarding units, corrugated plate fire-retarding plates are adopted, the thickness of the fire-retarding plates is 10mm, the diameter of the fire-retarding plates is 150mm, and the characteristic aperture h of the fire-retarding plates ₁ All 0.45mm. The long-time burn-resistant test is carried out by adopting a mixed gas of normal hexane and air (the volume concentration of the normal hexane is 2.1 percent), the highest temperature of the combustion side is 850 ℃, the highest temperature of the protection side during combustion is 98 ℃, and the highest temperature of the protection side after gas stopping is 376 ℃.

The pipe end fire-resistant flame arrestor 100 of example 1 and the conventional common fire-resistant flame arrestor were subjected to a long-time fire test, and the long-time fire-resistant test was performed at a constant flow rate, and the combustion side temperature change and the protection side temperature change were recorded. After 2h of combustion, the air supply is stopped, and the temperature change of the protection side is continuously recorded until the temperature of the protection side starts to drop. Thus, the test results of the following table were obtained:

	example 1	Comparative example 1
			Highest temperature of combustion side of burn-resistant unit 7	720℃	850℃
Highest temperature of fire-retardant unit 4 when protecting side burning	72℃	98℃
			Highest temperature of fire-retardant unit 4 when protection side stops gas	205℃	376℃

As is clear from the above table, when the combustion is performed while the outer side of the burn-resistant unit 7 grows, the combustible gas continues to propagate from the first connection chamber 2, the firestop unit 4, the second connection chamber 5, and the burn-resistant unit 7 to the atmosphere. The temperature of the combustion side of the fire resisting unit 7 and the temperature of the protection side of the fire resisting unit 4 are greatly reduced compared with the data of the comparative example 1 by lifting the flame surface outside the fire resisting unit 7, and obviously, compared with the conventional common fire resisting flame arresters, the pipe end fire resisting flame arrestor 100 provided by the invention remarkably improves the long-term fire resisting performance.

Example 2

As shown in fig. 2, the second connecting chamber 5 is constructed in a bell-mouth structure with a diameter increasing from bottom to top, thereby, the burn-resistant unitThe cross-sectional area of element 7 is greater than the cross-sectional area of firestop unit 4, i.e. S ₂ ＞S ₁ 。

At the same time, the diameters and thicknesses of the fire-resistant unit 7 and the firestop unit 4 are set to be consistent, and the average characteristic dimension h of the pores of the fire-resistant unit 7 ₂ Average pore characteristic dimension h of firestop element 4 ₁ Small, specific h ₂ May be 0.45mm.

Otherwise, the same as in example 1 was conducted.

Thus, by making the cross-sectional area of the burn-resistant unit 7 larger than that of the firestop unit 4, i.e., S ₂ ＞S ₁ The average characteristic dimension of the pores of the fire-resistant unit 7 is smaller than that of the fire-retardant unit 4, namely h ₂ ＜h ₁ Thereby realizing the effective flow area S of the burn-resistant unit 7 _{2 have} Less than the effective flow area S of the fire-retarding unit 4 _{1 has} 。

Example 3

The average characteristic sizes of pores of the fire-resistant unit 7 and the fire-retardant unit 4 are kept consistent, and are 0.8mm, namely h ₂ ＝h ₁ . And, the diameter of the burn-resistant unit 7 is reduced to 140mm.

Otherwise, the same as in example 1 was conducted.

Thus, by making the cross-sectional area of the burn-resistant unit 7 smaller than that of the firestop unit 4, i.e., S ₂ ＜S ₁ The average characteristic size of the pores of the fire-resistant unit 7 is equal to that of the fire-retardant unit 4, namely h ₂ ＝h ₁ Thereby realizing the effective flow area S of the burn-resistant unit 7 _{2 have} Less than the effective flow area S of the fire-retarding unit 4 _{1 has} 。

Example 4

The burn-resistant unit 7 is of a multiple module design, and in particular, 4 corrugated plate firestop trays may be used. The fire-retardant plate is of a closed structure, so that gas and flame are prevented from passing through. As shown in fig. 4, the burn-resistant unit 7 is formed of a plurality of corrugated plate fire-retardant plates, and the center of the burn-resistant unit 7 is a closed structure 71. The second connecting chamber 5 is configured in a bell-mouth structure with a diameter increasing from bottom to top, whereby the cross-sectional area of the burn-resistant unit 7 is larger than the cross-sectional area of the firestop unit 4, i.e. S ₂ ＞S ₁ 。

The inside of the second connection cavity 5 is filled with air or with a low thermal conductivity material.

Otherwise, the same as in example 2 is carried out.

Example 5

The burn-resistant unit 7 is a non-uniform thickness burn-resistant unit.

As shown in fig. 5, the burn-resistant unit 7 is configured such that the center region thickness is greater than the circumferential edge thickness. Specifically, the thickness of the central region of the burn-resistant unit 7 is 30mm, and the diameter of the central region is 80mm. The thickness of other areas is 10mm, and the overall outer diameter is 150mm.

Otherwise, the same as in example 1 was conducted.

Example 6

The pipe end fire-resistant flame arrester 100 takes the type IIA as an example of the explosion-proof grade, and the specification of the flame arrester is DN100.

The lower dimension of the second connecting cavity 5 is DN200, the upper dimension of the second connecting cavity 5 is DN220, and the second supporting piece 6 is matched with the upper portion of the second connecting cavity 5 to place the burn-resistant unit 7. The diameter of the burn-resistant unit 7 is 220mm.

The fire-resistant unit 7 adopts a corrugated plate fire-retardant plate as well, and the average characteristic dimension h of the pore space ₂ 0.8mm and a porosity of 0.65. Thickness L in axial direction ₂ Is 10mm.

At the same time, the burn-resistant unit 7 is also provided with a circulation adjusting mechanism 11. As shown in fig. 6, the circulation adjusting mechanism 11 is provided at the upper end of the burn-resistant unit 7, and the circulation adjusting mechanism 11 is made of a temperature memory alloy. As shown in fig. 6a, the flow-through adjustment mechanism 11 comprises a plurality of evenly spaced apart adjustment plates 111. Initially, the adjustment plates 111 contract such that the gaps between adjacent adjustment plates 111 are larger, thereby making the effective flow area of the burn-resistant unit 7 larger. When combustion occurs at the outer side of the fire resistant unit 7, as shown in fig. 6a, the adjusting plates 111 made of the temperature memory alloy are unfolded when reaching a predetermined high temperature, so that gaps between adjacent adjusting plates 111 are reduced, and accordingly the adjusting plates 111 seal the flow area of the fire resistant unit 7 more, the effective flow area of the fire resistant unit 7 is reduced, the air flow speed is accelerated, and the flame height is effectively raised. Wherein the predetermined temperature is not lower than 80 ℃, preferably at 120 ℃ or higher.

Otherwise, the same as in example 1 was conducted.

Thus, by making the cross-sectional area of the burn-resistant unit 7 larger than that of the firestop unit 4, i.e., S ₂ ＞S ₁ The average characteristic size of the pores of the fire-resistant unit 7 is equal to that of the fire-retardant unit 4, namely h ₂ ＝h ₁ At the same time, the effective flow area S of the burn-resistant unit 7 is realized by the automatic adjustment of the flow adjusting mechanism 11 when the preset temperature is reached _{2 have} Less than the effective flow area S of the fire-retarding unit 4 _{1 has} 。

Example 7

The fire-resistant unit 7 is also a corrugated plate fire-retardant plate, a central hole is reserved, and the average characteristic dimension h of the pore is ₂ 0.8mm and a porosity of 0.65. Thickness L in axial direction ₂ Is 10mm.

Meanwhile, the burn-resistant unit 7 is also provided with a circulation adjusting mechanism 110. As shown in fig. 7, the flow-through adjusting mechanism 110 is disposed at the lower end of the burn-resistant unit 7, and may be configured to include at least two flaps of a barrier 121 and a fusible link unit 122 for defining the barrier 121, the barrier 121 being disposed at the lower end of the burn-resistant unit 7, and the fusible link unit 122 penetrating the burn-resistant unit 7 and extending upward. As shown in fig. 7a, initially, the fusible link unit 122 defines a multi-flap barrier 121 overlapping together. As shown in fig. 7b, when combustion occurs at the outside of the burn-resistant unit 7 and the fusible link unit 122 is fused when a predetermined temperature is reached, the multi-flap barrier 121 is automatically opened, thereby reducing the effective flow area of the burn-resistant unit 7.

Preferably, when the rain cover 10 is provided, the fusible link unit 122 is formed integrally with the fusible link 9. After the fusible link unit 122 is fused, on the one hand, the rain cover 10 is opened to one side of the tube-end burn-resistant flame arrester 100, preventing heat accumulation. On the other hand, after the fusible link unit 122 is fused, the baffles 121 originally overlapped are opened to accelerate the air flow speed and effectively raise the flame height by the effective flow area of the burn-resistant unit 7.

Otherwise, the same as in example 1 was conducted.

Thus, by making the cross-sectional area of the burn-resistant unit 7 larger than that of the firestop unit 4, i.e., S ₂ ＞S ₁ The average characteristic size of the pores of the fire-resistant unit 7 is equal to that of the fire-retardant unit 4, namely h ₂ ＝h ₁ At the same time, the effective flow area S of the burn-resistant unit 7 is realized by the automatic adjustment of the flow adjusting mechanism 110 when the preset temperature is reached _{2 have} Less than the effective flow area S of the fire-retarding unit 4 _{1 has} 。

Example 8

The lower dimension of the second connecting cavity 5 is DN200, the upper portion of the second connecting cavity 5 is matched with the second supporting piece 6 to place the burn-resistant unit 7, and the upper dimension of the second connecting cavity 5 is DN150.

Meanwhile, as shown in fig. 8, a heat dissipation mechanism 13 may be further provided inside the second connection chamber 7. The heat dissipation mechanism 13 may be, for example, a heat pipe, where the heat pipes are provided with multiple paths and are connected to each other, and are uniformly arranged in the second connection cavity 7. The heated section of the heat pipe is located inside the second connection cavity 7, and the heat release end is located outside the second connection cavity 7. When combustion occurs outside the burn-resistant unit 7, the heat dissipation mechanism 13 can further reduce the heat transfer of the burn-resistant unit 7 to the firestop unit 4. On the one hand, the air in the second connecting cavity 5 is used as a heat conducting carrier to reduce the heat conducting rate, and on the other hand, the heat dissipation mechanism 13 is used for reducing the heat transfer of the burning-resistant unit 7 to the fire retarding unit 4.

Otherwise, the same as in example 1 was conducted.

Thus, by making the cross-sectional area of the burn-resistant unit 7 larger than that of the firestop unit 4, i.e., S ₂ ＞S ₁ The average characteristic size of the pores of the fire-resistant unit 7 is equal to that of the fire-retardant unit 4, namely h ₂ ＝h ₁ Thereby realizing the effective flow area S of the burn-resistant unit 7 _{2 have} Less than the effective flow area S of the fire-retarding unit 4 _{1 has} . And simultaneously, when the heat dissipation mechanism 13 burns outside the fire resisting unit 7, the heat transfer of the fire resisting unit 7 to the fire retarding unit 4 is further reduced.

According to the pipe end fire-resistant flame arrester 100, the effective flow area of the fire-resistant unit 7 is smaller than that of the fire-resistant unit 4, so that the combustible gas has high flow rate when being discharged out of the fire-resistant unit 7, the flame surface height is further improved, and the accumulation of heat on the surface of the fire-resistant unit 7 is remarkably reduced. Meanwhile, the fire-resistant units 7 are distributed above the fire-retardant units 4 at intervals, so that a heat-insulating cavity between the fire-resistant units 7 and the fire-retardant units 4 is formed in the second connecting cavity 5, and the heat transfer of the fire-resistant units 7 is further reduced by the heat-insulating cavity, so that the pipe-end fire-resistant flame arrester 100 can be effectively ensured to have long-term fire resistance. The fire-retarding unit 4 has a larger heat conduction area, so that the dissipation of external heat on the side of the fire-retarding unit 4 is further accelerated, and the heat conduction to the inside is further avoided. In addition, the horn-shaped structural design of the first connecting cavity 2 and the second connecting cavity 5 enables the exhaled combustible gas to have the effect of cooling the burning-resistant unit 7, and the burning resistance of the pipe end burning-resistant flame arrester 100 is further improved.

In the description of the present invention, it should be understood that the terms "first," "second," and the like are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include one or more such feature. In the description of the present invention, the meaning of "a plurality" is two or more, unless explicitly defined otherwise.

In the present invention, unless explicitly specified and limited otherwise, the terms "mounted," "connected," "secured," and the like are to be construed broadly and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the above terms in the present invention can be understood by those of ordinary skill in the art according to the specific circumstances.

Furthermore, in the description herein, reference to the terms "one embodiment," "some embodiments," "examples," "specific examples," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiments or examples. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

Finally, it should be noted that the above description is only of a preferred embodiment of the invention and is not to be construed as limiting the invention in any way. Although the invention has been described in detail with reference to the foregoing embodiments, it will be apparent to those skilled in the art that modifications may be made to the techniques described in the foregoing examples, or equivalents may be substituted for elements thereof. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A fire arrestor of the tube end burn-resistant type, comprising:

the connecting device comprises a first connecting cavity (2), wherein a connecting flange (1) is formed at the lower end of the first connecting cavity (2);

a fire-retarding unit (4) installed at the upper port of the first connection cavity (2);

the second connecting cavity (5) is connected to the upper end of the first connecting cavity (2); and

a burn-resistant unit (7) mounted at the upper port of the second connection cavity (5);

wherein the effective flow area of the fire-resistant unit (7) is larger than the flow area of the connecting flange (1) and smaller than the effective flow area of the fire-retardant unit (4),

an insulating cavity is formed inside the second connecting cavity (5) between the fire-resistant unit (7) and the fire-retarding unit (4).

2. The pipe-end fire-resistant flame arrester of claim 1, characterized in that the effective flow area of the fire-resistant unit (7) is smaller than the effective flow area of the fire-resistant unit (4) by adjusting the average characteristic dimensions h of the pores, the cross-sectional area S, and the number of flow-through pores of the fire-resistant unit (4) and the fire-resistant unit (7).

3. The fire arrestor of the pipe end fire resistant type according to claim 1, characterized in that the fire resistant unit (7) is provided with a flow-through adjusting mechanism (11),

the circulation adjusting mechanism (11) is configured to be capable of automatically expanding when the outside of the fire resisting unit (7) burns and reaches a preset temperature so as to seal the circulation area of the fire resisting unit (7), thereby reducing the effective circulation area of the fire resisting unit (7) and enabling the effective circulation area of the fire resisting unit (7) to be smaller than the effective circulation area of the fire retarding unit (4).

4. A pipe end fire resistant flame arrester according to claim 3, wherein the flow regulating mechanism (11) is arranged at the upper end of the fire resistant unit (7), the flow regulating mechanism (11) is made of a temperature memory alloy, and comprises a plurality of regulating plates (111) which are uniformly distributed at intervals, and the predetermined temperature is not lower than 80 ℃.

5. The fire arrestor as defined in claim 3, wherein the flow-through adjusting mechanism is configured to include at least two flaps of a baffle plate (121) and a fusible link unit (122) for defining the baffle plate (121), the baffle plate (121) being disposed at a lower end of the fire resistant unit (7), the fusible link unit (122) extending through the fire resistant unit (7) and upward,

the fusible link unit (122) is configured to initially define a plurality of flaps of the barrier (121) overlapping and to fuse when the predetermined temperature is reached to cause the flaps of the barrier (121) to open automatically.

6. The tube end fire resistant flame arrestor of claim 1, wherein the thermally insulated cavity is filled with a low thermal conductivity gas or material.

7. The fire arrestor of the pipe end burn-resistant type according to claim 6, characterized in that the second connecting cavity (7) is provided with a heat dissipation mechanism (13).

8. The pipe end fire resistant flame arrester of claim 7 wherein the heat dissipation mechanism (13) is a heat pipe, and the heated section of the heat pipe is located inside the second connection cavity (7), and the heat dissipation end is located outside the second connection cavity (7).

9. The tube-end fire arrestor according to any of claims 1 to 8, characterized in that the first connection cavity (2) is configured to comprise a bell-mouth shaped body (21) with a diameter increasing from bottom to top and a connection cylinder (22) for connecting the connection flange (1).

10. A fire arrestor of the tube end burn-resistant type according to claim 9, characterized in that a first support (3) is provided at the upper port of the bell-mouth shaped body (21) for mounting the fire-arresting unit (4).

11. The pipe end fire resistant flame arrester according to claim 9, characterized in that a second support (6) is provided at the upper port of the second connection cavity (5) for mounting the fire resistant unit (7).

12. The pipe-end fire resistant flame arrester according to claim 9, characterized in that the first connection cavity (2) and the second connection cavity (5) form a fixed connection by means of a connection unit (8), the connection unit (8) comprising a fastener and a sealing gasket.

13. The pipe end burning-resistant flame arrester according to claim 1, characterized in that a rain cover (10) is arranged above the burning-resistant unit (7), the rain cover (10) is limited by a fusible connecting piece (9), the fusible connecting piece (9) can be burned out outside the burning-resistant unit (7) and reach a preset temperature, and the rain cover (10) can be automatically sprung out after the fusible connecting piece (9) is burned out.