CN214485361U

CN214485361U - Self-triggering passive fire extinguishing device for cable intermediate joint

Info

Publication number: CN214485361U
Application number: CN202022555616.9U
Authority: CN
Inventors: 杨韬; 张�杰; 严帆
Original assignee: 3M China Ltd
Current assignee: 3M China Ltd
Priority date: 2020-11-06
Filing date: 2020-11-06
Publication date: 2021-10-26
Anticipated expiration: 2030-11-06

Abstract

The utility model provides a from passive extinguishing device of formula that triggers for cable intermediate head. The self-triggering passive fire suppression device includes a flexible tube and a housing. A flexible tube is wrapped around and secured to the main body portion of the cable intermediate joint, the flexible tube being pressure-filled with a fluid fire extinguishing agent. The shell encloses the cable intermediate joint and the flexible pipe. The fluid fire suppression agent is preferably a fluoroisohexanone fluid fire suppression agent. The utility model discloses can realize the production of automated inspection flame and produce early quick fire extinguishing at flame with simple passive structure to be applicable to the environment that the space is limited, unmanned and supervised. Furthermore, the utility model discloses can not cause harmful effects to power transmission system and surrounding environment when putting out a fire.

Description

Self-triggering passive fire extinguishing device for cable intermediate joint

Technical Field

The utility model relates to a fire extinguishing apparatus. More specifically, the utility model relates to a passive extinguishing device of formula that triggers certainly for cable intermediate head.

Background

The intermediate joint of medium or high voltage cable is easy to generate electric arc and flame when short circuit fault occurs, if no special fire-proof device is provided, the flame is easy to ignite the surrounding cable or other objects, and the power transmission system is seriously damaged or even disastrous results are caused. At present, the traditional fire-proof device of the cable intermediate joint mainly has the following two types: one type of fire protection device is a shell made of a high-strength flame-retardant material and used for enclosing a cable intermediate joint, and on the basis, the shell can be filled with a solid flame-retardant material; another type of fire protection device automatically senses the generation of a flame and extinguishes the fire through an electrical system that includes sensors.

In practical applications, both of the above two types of fire protection devices have great limitations. For the first type of fire protection device, when the housing of the cable intermediate joint is broken down by electric arcs or flames, the housing can play a certain role in blocking flames, relieving pressure and preventing explosion. However, once a fire has been generated, such devices do not quickly and efficiently extinguish the fire, particularly in a timely manner early in the generation of the fire and to inhibit the spread of the fire. Even in the case where the case is filled with the solid fire retardant material, the released solid fire retardant material cannot rapidly and effectively extinguish the flame at an early stage of the generation of the flame after the case is broken down. Furthermore, the released solid fire-retardant material scatters in the ground and thus clutter the environment and, when cables with such fire protection devices are laid in an open natural environment, damage to the environment is caused because the released solid fire-retardant material is generally difficult to naturally degrade. The second type of fire protection device relies on an active system for control, requiring the provision of power sources, sensors, containers or pipes for storing the fire extinguishing agent and other associated equipment, which is complex and costly. Furthermore, such a closely controlled large-scale fire protection system requires sufficient installation space and a suitable working environment and requires regular inspection and maintenance, and therefore such fire protection devices are not suitable for use in a limited-space, harsh-condition and unattended environment, which is very common in power transmission systems.

Accordingly, there is a need for an improved fire protection arrangement for a conventional cable intermediate joint. On the one hand, it is desirable to be able to achieve a fast and efficient fire suppression with a passive device of simple construction and easy maintenance, making the device also suitable for use in confined space, unattended environments; on the other hand, it is desirable to extinguish fires without causing additional damage to the power transmission system and the surrounding environment.

SUMMERY OF THE UTILITY MODEL

The utility model aims at improving the fire protection device of traditional cable intermediate head, providing a simple structure, low cost and need not the passive extinguishing device of the special formula of triggering of maintaining certainly, producing the early auto-induction flame production of flame and putting out a fire fast. Another object of the present invention is to provide a fire extinguishing system that does not adversely affect the power transmission system and the surrounding environment.

The above-mentioned purpose is realized through the passive extinguishing device of self-triggering formula that is used for cable intermediate head according to the utility model discloses a.

According to the utility model discloses a from passive extinguishing device of formula that triggers includes flexible pipe and casing. A flexible tube is wrapped around and secured to the main body portion of the cable intermediate joint, the flexible tube being pressure-filled with a fluid fire extinguishing agent. The shell encloses the cable intermediate joint and the flexible pipe.

In one embodiment, the first end of the flexible tube is a closed end fixed to the body portion or housing of the cable intermediate joint, the second end opposite the first end is an open end fixed to the housing, and the second end is temporarily sealed.

In one embodiment, a one-way valve is attached to the second end of the flexible tube that allows only one-way flow of the fluid fire suppressant into the flexible tube.

In one embodiment, a pressure gauge is connected to the second end of the flexible tube.

In one embodiment, the first end and the second end of the flexible tube opposite the first end are closed ends secured to a body portion or housing of the cable intermediate joint.

In one embodiment, the housing is formed by two half-shells connected to each other and a hollow space is formed between the housing and the cable intermediate joint and the flexible tube.

In one embodiment, the flexible tubing is pressure filled with a fluoroisohexide fluid fire extinguishing agent.

In one embodiment, the flexible tube is a polytetrafluoroethylene flexible tube.

In one embodiment, the housing is a metal housing or a composite housing.

In one embodiment, the flexible tube is filled with a fluid fire extinguishing agent at a pressure of not less than 0.1 Mpa.

According to the utility model discloses a from passive extinguishing device of formula that triggers has realized simultaneously storage fire extinguishing agent, response flame production, the function of putting out a fire in flame production early self-triggering fast through the flexible pipe of densely covered winding on cable intermediate head's main part, need not equipment such as power, sensor among the traditional fire protection system, and simple structure is compact, and low cost is applicable to the limited environment in space and need not the special messenger and takes care of and maintain. On the other hand, the preferred fluid fire extinguishing agent employed is fluoroisohexanone fluid fire extinguishing agent, which is clean, low toxicity, non-corrosive, non-conductive and easily vaporizable, and does not adversely affect the power transmission system and the surrounding environment.

Drawings

Embodiments of the invention will be described below, by way of example only, with reference to the accompanying drawings. In the drawings, like features or components are designated with like reference numerals, and the drawings are not necessarily drawn to scale, and wherein:

fig. 1 shows the internal structure of a self-triggering passive fire extinguishing device for cable intermediate joints according to an embodiment of the present invention;

figures 2 and 3 show the housing of the self-triggering passive fire extinguishing device;

fig. 4 shows a one-way valve of the self-triggering passive fire extinguishing device;

fig. 5 shows a self-triggering passive fire extinguishing device for a cable intermediate joint according to another embodiment of the present invention.

Detailed Description

The following description is merely exemplary in nature and is not intended to limit the present disclosure, application, or uses. It should be understood that throughout the drawings, like reference numerals indicate like or similar parts and features. The drawings are only schematic representations of the concepts and principles of the embodiments of the present invention, and do not necessarily show the specific dimensions and proportions of the various embodiments of the present invention. Certain features that are in certain figures may be shown exaggerated in detail in order to illustrate relevant details or structures of embodiments of the invention.

In the description of the embodiments of the present invention, the terms of orientation used in relation to "up", "down", "left" and "right" are described in terms of positions of up, down, left and right in the views shown in the drawings. In practical applications, the positional relationships of "up", "down", "left" and "right" used herein may be defined according to practical situations, and the relationships may be reversed.

Fig. 1 shows the internal structure of a self-triggering passive fire extinguishing device 1 for cable intermediate joints according to one embodiment of the present invention. As shown in fig. 1, a self-triggering passive fire extinguishing device 1 is provided at a cable intermediate joint 4 connecting a first cable 2 and a second cable 3. The self-triggering passive fire extinguishing apparatus 1 includes a flexible pipe 10, and the flexible pipe 10 is wound and fixed on a main body portion of the cable intermediate joint 4 at a certain interval. Preferably, the flexible tube 10 is wound evenly around the main portion of the cable intermediate joint 4, and the spacing between adjacent turns should not be too large. The self-triggering passive fire extinguishing device 1 further comprises a housing 20 enclosing the cable intermediate joint 4 and the flexible pipe 10 wound thereon. In the present embodiment, the housing 20 is a two-half housing made up of a first half housing 22 shown in fig. 1 and 2 and a second half housing 24 shown in fig. 3. Wherein the first and

second half shells

22 and 24 are generally semi-cylindrical and are respectively provided with a first connection flange 222 and a second connection flange 242 along respective edges thereof, a plurality of mounting holes 224 are provided in the first connection flange 222, and a plurality of mounting holes 244 aligned with the mounting holes 224 are provided in the second connection flange 242, such that the first and

second half shells

22 and 24 can be connected to form the complete shell 20 by fasteners, such as bolts, etc., passing through the mounting holes 224 and the mounting holes 244. As shown in fig. 1, the inner diameter of the housing 20 at the middle portion is larger than the maximum diameter of the cable intermediate joint 4 wound with the flexible tube 10, the inner diameter of the housing 20 at the two ends is gradually reduced to be equal to or slightly larger than the outer diameter of the first cable 2 and the second cable 3, and the two ends of the housing 20 and the first cable 2 and the second cable 3 can be sealed by using a suitable sealing material (e.g., a flame-retardant elastic rubber pad, etc.) and tightly pressed against the surfaces of the first cable 2 and the second cable 3 through the housing 20, so that a substantially closed hollow space is formed between the housing 20 and the cable intermediate joint 4 and the flexible tube 10. In this embodiment, the first end 102 of the flexible tube 10 is a closed end and is fixed to the main part of the cable intermediate joint 4, for example, the first end 102 may be tethered to the main part of the cable intermediate joint 4 by a heat resistant fiberglass ribbon (not shown); the second end 104 of the flexible tube 10 is an open end and is secured to the housing 20. As shown in fig. 2, a hole 226 is provided in the first housing half 22 for receiving and securing the second end 104 of the flexible pipe 10, the second end 104 of the flexible pipe 10 being secured in the hole 226, for example by a snap or screw connection.

The flexible tube 10 may be filled with a fluid fire extinguishing agent at a certain pressure (typically not less than 0.1Mpa) through the open second end 104 before or after the flexible tube 10 is wrapped around the body portion of the cable intermediate joint 4 and secured. The second end 104 may then be temporarily or permanently sealed. In the embodiment shown in fig. 1, a one-way valve 30 is provided at the aperture 226 of the first housing half 22 to temporarily seal the second end 104. Fig. 4 schematically shows a cross-sectional view of the one-way valve 30. The one-way valve 30 may include an inlet 302 connected to a fluid-filled device or pressure gauge, an outlet 304 connected to the second end 104 of the flexible tube 10, and a spring 306 and valve plate 308 positioned between the inlet 302 and the outlet 304. In the closed condition, the force of the spring 306 causes the valve member 308 to abut and block the inlet 302, thereby sealing the flexible pipe 10. When a fluid filling device or pressure gauge is connected to the inlet 302, the pressure of the fluid filling device or pressure gauge will compress the spring 306 and push the valve plate 308 open, thereby allowing fluid filling or pressure measurement. When the charging device or pressure gauge is removed, the spring 306 springs back and again causes the valve plate 308 to block the inlet 302. Thus, the one-way valve 30 allows only one-way flow of the fluid fire suppressant into the flexible tube 10, but does not allow the fluid fire suppressant to flow out of the flexible tube 10. In other embodiments, the second end 104 of the flexible pipe 10 may be temporarily or permanently sealed by any suitable other means, such as mechanical sealing, fusion sealing, thread sealing, etc.

Fig. 5 shows an embodiment of a self-triggering passive fire extinguishing device 1 with a pressure gauge connected thereto. As described above, the pressure gauge 40 is connected to the inlet 302 of the check valve 30 to measure the pressure of the fluid fire suppressant in the flexible tube 10. The pressure gauge 40 may be connected only temporarily during the process of filling the flexible tube 10 with the fluid fire extinguishing agent to measure whether the pressure reaches a desired value, or may be connected to the second end 104 of the flexible tube 10 for a long time, so that the pressure in the flexible tube 10 may be monitored while the second end 104 of the flexible tube 10 is sealed to replenish the fluid fire extinguishing agent in time.

The principle and operation of the self-triggering passive fire-extinguishing device 1 is described in detail below.

The flexible tube 10 is made of a material having a certain heat resistance but a melting point lower than the flame temperature, and the housing 20 is made of a high-strength refractory material. A sufficient amount of fluid fire suppressant is sealed in the flexible tube 10 at a certain pressure. Once the cable intermediate joint 4 is short-circuited to cause a fire, the flexible tube 10 densely wound around the main body portion of the cable intermediate joint 4 is rapidly burned through, and the fluid fire extinguishing agent in the flexible tube 10 is rapidly sprayed and dispersed in the inner space of the housing 20 under pressure. The housing 20 enclosing the cable intermediate joint 4 and the flexible tube 10 is not susceptible to burning through, isolates the flame from the outside environment and provides a substantially enclosed interior space so that the fluid fire suppressant surrounding the fire point reaches a sufficient fire extinguishing concentration to quickly and efficiently extinguish the flame in the early stages of flame generation.

The fluid fire extinguishing agent filled in the flexible tube 10 is preferably a clean, non-toxic, non-corrosive, non-conductive and easily vaporizable fire extinguishing agent, such as fluoroisocaprone (C)₆F₁₂O), and the like. Such fluid fire extinguishing agents are commercially available, for example, Novec 1230 from 3M company. Fluoroisohexanones fluid fire extinguishing agents combine extremely low toxicity with high fire extinguishing efficiency, acting to extinguish fires primarily by rapidly removing the heat of a fire source, and are therefore particularly well suited for extinguishing fires within the generally enclosed interior space of housing 20. The boiling point of the fluoroisocaprone fluid fire extinguishing agent under the standard atmospheric pressure is about 49.2 ℃, and the fluoroisocaprone fluid fire extinguishing agent is liquid under normal temperature and normal pressure, so that the filling operation is convenient. In addition, the fluoroisohexanone fluid fire extinguishing agent evaporates quickly, is non-corrosive and non-conductive in both liquid and gaseous states, has good compatibility, does not damage a cable intermediate joint or cause other electrical risks, does not leave messy residues or cause other adverse effects to the environment, and therefore, the power transmission system can always keep normal operation. In other embodiments, any other suitable fluid fire extinguishing agent may be used.

Due to the extremely high currents passing through the medium and high voltage cables, the normal operating temperature of the cable intermediate joint 4 is high, typically about 130 ℃, while the flame temperature is typically around 400 ℃. Thus, the melting point of the material of the flexible tube 10 should be above the normal operating temperature of the cable intermediate joint 4 and below the flame temperature to ensure a rapid response early in the flame generation. For example, the material of the flexible tube 10 may be Polytetrafluoroethylene (PTFE) or other suitable material having a melting point typically above 200 ℃ and below 400 ℃. In other embodiments, any other suitable material may be selected for the flexible tube 10.

The housing 20 may be made of a high strength material, such as a metal or composite material. The housing 20 provides reliable protection for the cable intermediate joint 4 and the flexible tubing 10 thereon, in addition to providing flame isolation, a closed space for the fluid fire suppressant to achieve the desired fire suppression concentration.

According to the utility model discloses a from triggering formula passive extinguishing device 1 simple structure is compact, small in size, low cost to need not the production that can monitor flame such as power and sensor and realize putting out a fire in flame production early stage fast. The flexible tube 10 densely wound around the main body portion of the cable intermediate joint 4 functions as both a container for storing a fluid fire extinguishing agent, a sensor for monitoring the generation of flames, and a self-triggering fire extinguisher. The housing 20 forms a compact outer package and effectively protects the self-triggering passive fire suppression device 1 from damage. Therefore, the self-triggering passive fire extinguishing device can be suitable for environments with limited space and severe conditions and does not need special persons to take care and maintain.

Further, the inner diameter, length, winding density, and pressure of the fluid fire extinguishing agent filled in the flexible tube 10 may be appropriately selected according to the conditions of the size of the cable intermediate joint, the kind of the fluid fire extinguishing agent, the requirement of fire extinguishing concentration, and the like, so that it can be applied to various cable intermediate joints.

In the preferred embodiment described above, the first end 102 of the flexible tube 10 is a closed end secured to the main portion of the cable intermediate fitting 4 and the second end 104 is secured to an open end of the housing 20 to facilitate filling with a fluid fire suppressant. The present invention is not limited thereto. For example, the second end 104 may be permanently sealed after filling with the fluid fire suppressant and secured to the main portion of the cable intermediate joint 4 as with the first end 102, or both the first end 102 and the second end 104 may be permanently sealed and secured to the housing 20. As mentioned above, the normal operating temperature of the cable intermediate joint 4 is high, and therefore the first end 102 and the second end 104 of the flexible tube 10 are preferably fixed to the main body portion of the cable intermediate joint 4 by heat-resistant fixing means, such as by bolting with glass fibre ribbons, or any other suitable fixing means.

The structure of the housing 20 in the above embodiment is also merely exemplary, and any other suitable housing may be used to form a substantially closed space enclosing the cable intermediate joint 4 and the flexible tube 10. For example, the housing may be divided into left and right housing halves connected to each other.

Here, an exemplary embodiment of a self-triggering passive fire extinguishing device according to the present invention has been described in detail, but it should be understood that the present invention is not limited to the specific embodiments described and illustrated in detail above. Numerous modifications and variations can be made by those skilled in the art without departing from the spirit and scope of the invention. All such variations and modifications are intended to fall within the scope of the present invention. Moreover, all the components described herein may be replaced by other technically equivalent components.

Claims

1. A self-triggering passive fire suppression device for a cable intermediate joint, comprising:

a flexible tube wrapped around and secured to the main body portion of the cable intermediate joint, the flexible tube being pressure-filled with a fluid fire extinguishing agent; and

a housing enclosing the cable intermediate joint and the flexible tube.

2. The self-triggering passive fire suppression apparatus for a cable intermediate joint of claim 1, wherein a first end of the flexible tube is a closed end fixed to a main body portion of the cable intermediate joint or the housing, a second end opposite the first end is an open end fixed to the housing, and the second end is temporarily sealed.

3. The self-triggering passive fire suppression apparatus for a cable intermediate joint of claim 2, wherein a one-way valve is connected to the second end of the flexible tube, the one-way valve allowing only one-way flow of the fluid fire suppressant into the flexible tube.

4. A self-triggering passive fire suppression apparatus for a cable intermediate joint as recited in claim 2, wherein a pressure gauge is connected to the second end of the flexible tube.

5. A self-triggering passive fire suppression apparatus for a cable intermediate joint as recited in claim 1, wherein the first end of the flexible tube and the second end opposite the first end are closed ends secured to the main body portion of the cable intermediate joint or the housing.

6. A self-triggering passive fire suppression apparatus for a cable intermediate joint as recited in claim 1, wherein the housing is formed of two half shells connected to each other and a hollow space is formed between the housing and the cable intermediate joint and the flexible tube.

7. The self-triggering passive fire suppression apparatus for a cable intermediate joint according to claim 1, wherein the flexible tube is pressure-filled with a fluoroisohexide fluid fire suppressant.

8. A self-triggering passive fire suppression apparatus for a cable intermediate joint as recited in claim 1, wherein the flexible tube is a polytetrafluoroethylene flexible tube.

9. A self-triggering passive fire suppression apparatus for a cable intermediate joint as recited in claim 1, wherein the housing is a metal housing or a composite housing.

10. The self-triggering passive fire suppression apparatus for a cable intermediate joint according to claim 1, wherein the flexible tube is filled with a fluid fire suppressant at a pressure of not less than 0.1 Mpa.