During the “Twelfth Five-Year Plan†period, China will form 10 million-ton-class and 10 50-million-ton extra-large coal enterprises. The degree of mechanization for coal mining in the country will reach over 75%, and the 12th Five-Year Plan will also control the number of coal mining enterprises. It is 4000. By 2015, the output of small coal mines below 300,000 tons will be reduced to 500 million tons, accounting for 13% of the country's total coal production. The total coal output will reach 3.6-3.8 billion tons, and large coal mines will account for 2.5 billion tons, which will increase from 56% during the 11th-five-year period to 66%. Large coal mines will become the dominant coal producers. This shows that China's coal industry will usher in a prosperous era. However, the continual development of any industry is accompanied by advantages and disadvantages. This is also true for the coal industry. Behind the prosperity of the industry is also hidden many flaws. In addition to environmental pollution, the frequent occurrence of coal mine safety accidents has attracted much attention.
Coal Mine Safety Issues and Safety Measures Requirements Development
The State Coal Supervision Bureau announced as early as November 2010 that it would establish a timetable for the improvement of the “six major systems†for underground safety hedging, and that the subregions will be rapidly promoted by coal mines nationwide. The coal mines in each province must be within the specified time limit. Complete the "Six Systems" safe-risk work. Before the end of 2011, all coal mines must complete monitoring and monitoring systems, air pressure self-rescue systems, water supply and rescue systems, communication and contact systems, underground personnel positioning systems and underground emergency hedging systems, as well as mine monitoring and monitoring, self-rescue pressure, and water supply. In order to improve the construction of the communications and communication system, key coal mines in China must complete the construction of the underground personnel positioning system. All state-owned coal mines, gas mines in natural gas and mines with high gas content in key coal mines and mining wells that are liable to self-firing coal seams must be completed in June 2012. Before the construction of the emergency hedging system was completed, other coal mines must complete the construction of the emergency hedging system by mid-2013.
The construction content of coal mine safety includes mine monitoring and monitoring system, underground personnel positioning system, underground emergency hedging system, mine pressure self-help system, mine water supply and rescue system, and six communication and communication systems, each of which corresponds to different degrees of safety. Hidden danger. Therefore, when constructing a good safety monitoring system during construction, it is necessary to understand various safety hazards and the coal mine geological structure environment. In addition, the type of monitoring of the coal mine system is also crucial. In general, coal mine safety monitoring can be divided into downhole safety monitoring and well safety monitoring. Because underground coal mines work deep into the inner surface of the ground, the geological and stratigraphic structures are relatively complex, and the environment is humid and warm, and the air quality is poor. Therefore, safety accidents are very likely to occur. Currently, in order to give full play to the role of the six security systems, the local coal mines have begun to use the various remote video monitoring systems to realize the intuitive grasp of the real-time video and data status of the downhole conditions. It is not only possible to record the occurrence at the underground working site. Video and gas values ​​can also be used to detect underground hazards in a timely manner to avoid mine accidents. The details of the installation and construction of these six systems are extremely extensive. Due to space limitations, the author hereby shares only personal observations on the coal mine video safety monitoring and explosion protection measures, with a view to advancing with you.
Explosion-proof requirements for coal mine safety monitoring equipment
According to statistics, the current domestic coal production accounts for about 40% of the world's total production, ranking first in the world. Coal mine safety accidents and casualties are also among the best. In the first half of 2010 alone, there were a total of 45 fatal accidents involving 10 or more deaths in China. The number of fatalities and missing persons was 764. This represented an increase of 12 cases and 266 cases last year, an increase of 36.4% and 53.4% ​​respectively. Among these accidents, gas explosions, collapsing rock formations, and gushing water in the rock face are the most common. From the point of view of safety precautions, the root cause of the occurrence of mine accidents is nothing more than the lack of coal mine safety monitoring equipment, unqualified standards for anti-explosion performance of equipment pipelines, and the backwardness of human monitoring and management methods. Therefore, how to reasonably apply security equipment to prevent coal mine explosions provides a great safety guarantee for coal mine safety monitoring.
In general, coal mine monitoring equipment must consider the possibility of explosion protection. The institutional composition, construction features, and wiring of equipment and equipment may cause explosions due to the presence of flammable and explosive gases or liquids in the coal mine. In addition, the high-temperature mixing of harmful gases in mining equipment may also cause coal mine explosions. In terms of monitoring systems, explosion-proof monitoring and construction must first eliminate the gas explosion and explosion caused by the operation of the monitoring system. Secondly, the level and material of the explosion-proof box should be selected based on the characteristics of the flammable and explosive materials on the site inside and outside the coal mine. . At present, there are mainly flammable and explosive materials outside coal mines: gasoline, diesel, liquid hydrocarbons, clean gasoline, methane, and some harmful gases such as hydrogen sulfide and CO may be present on site. The flammable and explosive materials in these coal mines are classified as Class II according to the basic classification of explosive substances; they are classified as Class A according to the classification of explosive gas mixtures; and classified according to the detonation temperature of explosive gases, they belong to Grades T1, T2, and T3, respectively. Therefore, the explosion-proof form of monitoring equipment in China's domestic regulations can refer to the following certifications for selection. Due to the fact that there are too many internationally compatible certifications, it is necessary to understand the contents of the following certification standards in order to understand the compatibility of explosion protection, so as to ensure the application of explosion-proof construction.
Explosion-proof public signs - the International Electrotechnical Commission (IEC) simply uses "Ex" or the European Electrotechnical Commission for short "EEx". Explosion-proof type marking: "d" for flameproof type; "o" for oil-filled type; "e" for increased safety type; "n" for non-spark type; "p" for positive pressure type; "m" for potting type ";q" for sand filling type; "s" for special type; "i" for intrinsically safe type, also subdivided into "ia" and "ib" grades.
Divided by the equipment environment: Class I and Class II.
According to the gas category: A, B, C.
The temperature is different from weiT1 to T6.
ExdIICT3, for example, represents explosion-proof explosion-proof equipment that can be used in Class II explosive gas atmospheres, C gas groups, temperature group T3, and so on.
Mine explosion-proof monitoring equipment selection
Due to the characteristics of low voltage, low current, low power and high frequency, video surveillance must be considered in light of the explosion-proof requirements of light, video transmission effect stability and reliability in the application of coal mine safety monitoring. Through the low-risk night vision camera equipment in the high-risk environment site, it is necessary not only to monitor the downhole running status of the coal mine, but also to provide high-quality video images. Therefore, in the explosion-proof requirements, the design and selection of coal mine monitoring equipment is even more important. The use of explosion-proof equipment is mainly to make the camera, lens, PTZ and other electrical equipment in the coal mine or underground hazardous environment will not cause combustion or explosion. Generally, these devices must have a substantial thickness of cast aluminum or stainless steel made of a strong anti-explosive enclosure, so in the construction and installation must pay attention to the following conditions to use the product in the coal mine video surveillance, these devices include:
Internal pressure explosion-proof protective cover
With the principle of internal pressure explosion proof, a protective cover made of cast aluminum or stainless steel with a certain thickness is used. The window glass is made of steel bullet material glass and has anti-knock function. The internal pressure explosion proof is usually tight, so the camera to be used must be able to withstand high Working temperature, while protecting the cover body must have the ability to resist corrosion. As for the installation of other accessories, in addition to internal heating and defogging and other equipment, the rest can be omitted, so as to avoid the opposite.
Internal pressure explosion-proof head
As for the part of the pan-tilt head, due to its own start-up motor circuit function, the starting current may generate sparks. Therefore, the explosion-proof pan/tilt head on the shell must be made of a high degree of confinement and is made of aluminum or stainless steel, and it must be able to withstand the acid and alkali corrosion and thickness. Has a certain ability to withstand internal pressure explosion. Although the rotary gimbal is large in size, the weight and the volume are both a challenge to the engineering personnel under the requirement of height installation.
Monitoring and designing explosion-proof junction box
The monitoring and explosion-proof control box used in the mining area is different from the general equipment connection equipment. From the connection and distribution of cables to the installation of front-end optical fibres or network transmission equipment, from the control receivers, the main power switch to the leakage protection circuit breaker, and arrester or surge absorption equipment, etc., are all associated with the explosion-proof control box. In addition to these devices, it is easy to cause gas and gas explosion. Therefore, the material and thickness of the explosion-proof junction box are particularly important. In general, the size of the size of the need to put all the equipment into the analog cable after the empty monitor and joint transition smoothly can be used, or because of the cost and the use of space is too small terminal box, but will cause the device temperature is too high Fall off.
Design and Construction of Coal Mine Explosion-proof Monitoring Equipment
For coal mine explosion-proof monitoring and control design, in addition to the design standards for explosion-proof monitoring and control systems, reference can also be made to the explosive environmental electrical and application design standards developed by China in the explosion protection section, among which GB50198-94, GA/T70-94, and GB/T15411- 1994, GB/T13953-1992 deserves special attention. When designing coal mine anti-explosion safety monitoring, the design and installation construction content shall be determined according to the categories, grades, characteristics of substances released from wells and wells, environmental conditions and other factors, so we also need to monitor the safety of coal mines during construction and Have some knowledge and understanding on the installation.
Explosion-proof construction and installation precautions for coal mine monitoring equipment
As shown in Figure 1, the coal mines mainly include the following points in monitoring and installation precautions for explosion-proof construction:
· The camera must be protected in an explosion-proof protective cover. The protective cover should also have a certain explosion-proof rating according to the needs of the environment;
· In the explosion-proof demand, infrared LED lighting camera is not suitable as a night vision monitor for low-light source;
In the mine explosion-proof zone, all pipelines except the grounding line and buried underground pipeline must be configured with metal galvanized steel pipes;
• If it is a rotary camera, it must be an explosion-proof pan/tilt or integrated explosion-proof structure.
· The camera must be installed with a grounding wire, either outside the well or in the well, so as to prevent the current generated by the leakage from causing explosion or explosion;
· Explosion-proof piping must be provided with a drainage device to prevent the condensation of water inside the pipe causing corrosion of the pipe wall;
• Do not use explosion-proof isolating joints (DRAIN) between the metal explosion-proof pipe and the metal galvanized pipe joint, and fill in the explosion-proof insulating adhesive (or explosion-proof pipe sand filler). The explosion-proof pipe sand filler is filled into the pipe to show at least The length of 45 cm (18 inches) is filled with the explosion-proof effect isolation to prevent the spark explosion caused by the short circuit in the pipeline;
Equipment and metal galvanized pipe or hose joints need to use explosion-proof isolation joint isolation;
• Explosion-proof zone and non-explosion-proof zone pipelines must also be isolated with explosion-proof isolation joints (Figure 2);
• All the pipes entering the equipment should be constructed as far as possible from the equipment or under the explosion-proof box to prevent the pipes from loosening or entering the water.
· The power line and video signal and the lightning protection grounding line must be in charge of configuration so as not to cause backfire to damage the device or cause explosion;
• The joints in the explosion-proof terminal equipment connection box must be lockable or screw terminal-fixed to prevent the circuit from coming off, especially if the power supply part causes spark explosion;
· The image doors of the camera terminal explosion-proof box are mostly fixed by screws. After the equipment is calibrated, it must be clockwise against the clockwise direction. The fixing screws should be tightened one by one to balance the pressure of the cover to prevent the airtightness from being produced due to poor sealing. Gas explosion
• The system ground must use a point grounding method. Copper wires shall be used for grounding, and closed loops shall not be formed, and shall not be mixed with high-current power grounds.
When the explosion-proof monitoring system adopts an independent grounding device, its grounding resistance must not exceed 4Ω (refer to the national regulations);
• If optical cable transmission is used in a coal mine, the optical transceiver housing on each well should be grounded and it is best to connect it to a device such as a camera. If the cable racks in the pits are connected, each slot should be grounded to ensure safety.
· Equipment that is most vulnerable to lightning strikes in coal mining areas is a front-end camera. If it is installed outside the well, lightning protection devices must be installed on the equipment.
The above are the matters needing attention and measures for the construction and installation of coal mine safety monitoring. Because coal mines are always filled with dangerous factors such as methane and coal dust explosions, there are also some mines that attempt to transmit wirelessly and mobile monitoring systems are beginning to enter coal mine safety surveillance. The video signal and the camera power supply are shared cable transmission. The camera itself has an ultra-high brightness LED white light. It is suitable for use under poor lighting conditions in underground mines or in non-illumination environments. It can take clear images under low illumination conditions, making coal mine safety monitoring. It can be more safely applied to the working area of ​​the deepest mining face of the coal mine, providing a broader security guarantee for safety monitoring under the mine. As for the digitization of coal mine safety monitoring, there are currently some coal mines that are connected to the local area network through switches. They also exchange local area networks through coal mines with existing twisted-pair cables and Ethernet switches, or use fiber optic Ethernet to exchange local area networks. The safety monitoring of coal mines has also gradually entered the all-IP networked field during the construction and installation phase.
Conclusion
The goal of realizing the safety production of coal mines is inseparable from the construction of safety precautions in mining areas. However, in the special monitoring environment of mining areas, the implementation of safety equipment must meet the explosion-proof requirements. Coal mine explosion-proof requirements should be the common basic conditions for all six coal mine safety systems. However, due to environmental changes in coal mines, it is difficult to fully control them. Therefore, only the construction and installation methods and conditions of the video surveillance system can be continuously improved, so that the conditions for explosion protection can be successfully achieved. Restricted to play a stronger monitoring performance.
Coal Mine Safety Issues and Safety Measures Requirements Development
The State Coal Supervision Bureau announced as early as November 2010 that it would establish a timetable for the improvement of the “six major systems†for underground safety hedging, and that the subregions will be rapidly promoted by coal mines nationwide. The coal mines in each province must be within the specified time limit. Complete the "Six Systems" safe-risk work. Before the end of 2011, all coal mines must complete monitoring and monitoring systems, air pressure self-rescue systems, water supply and rescue systems, communication and contact systems, underground personnel positioning systems and underground emergency hedging systems, as well as mine monitoring and monitoring, self-rescue pressure, and water supply. In order to improve the construction of the communications and communication system, key coal mines in China must complete the construction of the underground personnel positioning system. All state-owned coal mines, gas mines in natural gas and mines with high gas content in key coal mines and mining wells that are liable to self-firing coal seams must be completed in June 2012. Before the construction of the emergency hedging system was completed, other coal mines must complete the construction of the emergency hedging system by mid-2013.
The construction content of coal mine safety includes mine monitoring and monitoring system, underground personnel positioning system, underground emergency hedging system, mine pressure self-help system, mine water supply and rescue system, and six communication and communication systems, each of which corresponds to different degrees of safety. Hidden danger. Therefore, when constructing a good safety monitoring system during construction, it is necessary to understand various safety hazards and the coal mine geological structure environment. In addition, the type of monitoring of the coal mine system is also crucial. In general, coal mine safety monitoring can be divided into downhole safety monitoring and well safety monitoring. Because underground coal mines work deep into the inner surface of the ground, the geological and stratigraphic structures are relatively complex, and the environment is humid and warm, and the air quality is poor. Therefore, safety accidents are very likely to occur. Currently, in order to give full play to the role of the six security systems, the local coal mines have begun to use the various remote video monitoring systems to realize the intuitive grasp of the real-time video and data status of the downhole conditions. It is not only possible to record the occurrence at the underground working site. Video and gas values ​​can also be used to detect underground hazards in a timely manner to avoid mine accidents. The details of the installation and construction of these six systems are extremely extensive. Due to space limitations, the author hereby shares only personal observations on the coal mine video safety monitoring and explosion protection measures, with a view to advancing with you.
Explosion-proof requirements for coal mine safety monitoring equipment
According to statistics, the current domestic coal production accounts for about 40% of the world's total production, ranking first in the world. Coal mine safety accidents and casualties are also among the best. In the first half of 2010 alone, there were a total of 45 fatal accidents involving 10 or more deaths in China. The number of fatalities and missing persons was 764. This represented an increase of 12 cases and 266 cases last year, an increase of 36.4% and 53.4% ​​respectively. Among these accidents, gas explosions, collapsing rock formations, and gushing water in the rock face are the most common. From the point of view of safety precautions, the root cause of the occurrence of mine accidents is nothing more than the lack of coal mine safety monitoring equipment, unqualified standards for anti-explosion performance of equipment pipelines, and the backwardness of human monitoring and management methods. Therefore, how to reasonably apply security equipment to prevent coal mine explosions provides a great safety guarantee for coal mine safety monitoring.
In general, coal mine monitoring equipment must consider the possibility of explosion protection. The institutional composition, construction features, and wiring of equipment and equipment may cause explosions due to the presence of flammable and explosive gases or liquids in the coal mine. In addition, the high-temperature mixing of harmful gases in mining equipment may also cause coal mine explosions. In terms of monitoring systems, explosion-proof monitoring and construction must first eliminate the gas explosion and explosion caused by the operation of the monitoring system. Secondly, the level and material of the explosion-proof box should be selected based on the characteristics of the flammable and explosive materials on the site inside and outside the coal mine. . At present, there are mainly flammable and explosive materials outside coal mines: gasoline, diesel, liquid hydrocarbons, clean gasoline, methane, and some harmful gases such as hydrogen sulfide and CO may be present on site. The flammable and explosive materials in these coal mines are classified as Class II according to the basic classification of explosive substances; they are classified as Class A according to the classification of explosive gas mixtures; and classified according to the detonation temperature of explosive gases, they belong to Grades T1, T2, and T3, respectively. Therefore, the explosion-proof form of monitoring equipment in China's domestic regulations can refer to the following certifications for selection. Due to the fact that there are too many internationally compatible certifications, it is necessary to understand the contents of the following certification standards in order to understand the compatibility of explosion protection, so as to ensure the application of explosion-proof construction.
Explosion-proof public signs - the International Electrotechnical Commission (IEC) simply uses "Ex" or the European Electrotechnical Commission for short "EEx". Explosion-proof type marking: "d" for flameproof type; "o" for oil-filled type; "e" for increased safety type; "n" for non-spark type; "p" for positive pressure type; "m" for potting type ";q" for sand filling type; "s" for special type; "i" for intrinsically safe type, also subdivided into "ia" and "ib" grades.
Divided by the equipment environment: Class I and Class II.
According to the gas category: A, B, C.
The temperature is different from weiT1 to T6.
ExdIICT3, for example, represents explosion-proof explosion-proof equipment that can be used in Class II explosive gas atmospheres, C gas groups, temperature group T3, and so on.
Mine explosion-proof monitoring equipment selection
Due to the characteristics of low voltage, low current, low power and high frequency, video surveillance must be considered in light of the explosion-proof requirements of light, video transmission effect stability and reliability in the application of coal mine safety monitoring. Through the low-risk night vision camera equipment in the high-risk environment site, it is necessary not only to monitor the downhole running status of the coal mine, but also to provide high-quality video images. Therefore, in the explosion-proof requirements, the design and selection of coal mine monitoring equipment is even more important. The use of explosion-proof equipment is mainly to make the camera, lens, PTZ and other electrical equipment in the coal mine or underground hazardous environment will not cause combustion or explosion. Generally, these devices must have a substantial thickness of cast aluminum or stainless steel made of a strong anti-explosive enclosure, so in the construction and installation must pay attention to the following conditions to use the product in the coal mine video surveillance, these devices include:
Internal pressure explosion-proof protective cover
With the principle of internal pressure explosion proof, a protective cover made of cast aluminum or stainless steel with a certain thickness is used. The window glass is made of steel bullet material glass and has anti-knock function. The internal pressure explosion proof is usually tight, so the camera to be used must be able to withstand high Working temperature, while protecting the cover body must have the ability to resist corrosion. As for the installation of other accessories, in addition to internal heating and defogging and other equipment, the rest can be omitted, so as to avoid the opposite.
Internal pressure explosion-proof head
As for the part of the pan-tilt head, due to its own start-up motor circuit function, the starting current may generate sparks. Therefore, the explosion-proof pan/tilt head on the shell must be made of a high degree of confinement and is made of aluminum or stainless steel, and it must be able to withstand the acid and alkali corrosion and thickness. Has a certain ability to withstand internal pressure explosion. Although the rotary gimbal is large in size, the weight and the volume are both a challenge to the engineering personnel under the requirement of height installation.
Monitoring and designing explosion-proof junction box
The monitoring and explosion-proof control box used in the mining area is different from the general equipment connection equipment. From the connection and distribution of cables to the installation of front-end optical fibres or network transmission equipment, from the control receivers, the main power switch to the leakage protection circuit breaker, and arrester or surge absorption equipment, etc., are all associated with the explosion-proof control box. In addition to these devices, it is easy to cause gas and gas explosion. Therefore, the material and thickness of the explosion-proof junction box are particularly important. In general, the size of the size of the need to put all the equipment into the analog cable after the empty monitor and joint transition smoothly can be used, or because of the cost and the use of space is too small terminal box, but will cause the device temperature is too high Fall off.
Design and Construction of Coal Mine Explosion-proof Monitoring Equipment
For coal mine explosion-proof monitoring and control design, in addition to the design standards for explosion-proof monitoring and control systems, reference can also be made to the explosive environmental electrical and application design standards developed by China in the explosion protection section, among which GB50198-94, GA/T70-94, and GB/T15411- 1994, GB/T13953-1992 deserves special attention. When designing coal mine anti-explosion safety monitoring, the design and installation construction content shall be determined according to the categories, grades, characteristics of substances released from wells and wells, environmental conditions and other factors, so we also need to monitor the safety of coal mines during construction and Have some knowledge and understanding on the installation.
Explosion-proof construction and installation precautions for coal mine monitoring equipment
As shown in Figure 1, the coal mines mainly include the following points in monitoring and installation precautions for explosion-proof construction:
· The camera must be protected in an explosion-proof protective cover. The protective cover should also have a certain explosion-proof rating according to the needs of the environment;
· In the explosion-proof demand, infrared LED lighting camera is not suitable as a night vision monitor for low-light source;
In the mine explosion-proof zone, all pipelines except the grounding line and buried underground pipeline must be configured with metal galvanized steel pipes;
• If it is a rotary camera, it must be an explosion-proof pan/tilt or integrated explosion-proof structure.
· The camera must be installed with a grounding wire, either outside the well or in the well, so as to prevent the current generated by the leakage from causing explosion or explosion;
· Explosion-proof piping must be provided with a drainage device to prevent the condensation of water inside the pipe causing corrosion of the pipe wall;
• Do not use explosion-proof isolating joints (DRAIN) between the metal explosion-proof pipe and the metal galvanized pipe joint, and fill in the explosion-proof insulating adhesive (or explosion-proof pipe sand filler). The explosion-proof pipe sand filler is filled into the pipe to show at least The length of 45 cm (18 inches) is filled with the explosion-proof effect isolation to prevent the spark explosion caused by the short circuit in the pipeline;
Equipment and metal galvanized pipe or hose joints need to use explosion-proof isolation joint isolation;
• Explosion-proof zone and non-explosion-proof zone pipelines must also be isolated with explosion-proof isolation joints (Figure 2);
• All the pipes entering the equipment should be constructed as far as possible from the equipment or under the explosion-proof box to prevent the pipes from loosening or entering the water.
· The power line and video signal and the lightning protection grounding line must be in charge of configuration so as not to cause backfire to damage the device or cause explosion;
• The joints in the explosion-proof terminal equipment connection box must be lockable or screw terminal-fixed to prevent the circuit from coming off, especially if the power supply part causes spark explosion;
· The image doors of the camera terminal explosion-proof box are mostly fixed by screws. After the equipment is calibrated, it must be clockwise against the clockwise direction. The fixing screws should be tightened one by one to balance the pressure of the cover to prevent the airtightness from being produced due to poor sealing. Gas explosion
• The system ground must use a point grounding method. Copper wires shall be used for grounding, and closed loops shall not be formed, and shall not be mixed with high-current power grounds.
When the explosion-proof monitoring system adopts an independent grounding device, its grounding resistance must not exceed 4Ω (refer to the national regulations);
• If optical cable transmission is used in a coal mine, the optical transceiver housing on each well should be grounded and it is best to connect it to a device such as a camera. If the cable racks in the pits are connected, each slot should be grounded to ensure safety.
· Equipment that is most vulnerable to lightning strikes in coal mining areas is a front-end camera. If it is installed outside the well, lightning protection devices must be installed on the equipment.
The above are the matters needing attention and measures for the construction and installation of coal mine safety monitoring. Because coal mines are always filled with dangerous factors such as methane and coal dust explosions, there are also some mines that attempt to transmit wirelessly and mobile monitoring systems are beginning to enter coal mine safety surveillance. The video signal and the camera power supply are shared cable transmission. The camera itself has an ultra-high brightness LED white light. It is suitable for use under poor lighting conditions in underground mines or in non-illumination environments. It can take clear images under low illumination conditions, making coal mine safety monitoring. It can be more safely applied to the working area of ​​the deepest mining face of the coal mine, providing a broader security guarantee for safety monitoring under the mine. As for the digitization of coal mine safety monitoring, there are currently some coal mines that are connected to the local area network through switches. They also exchange local area networks through coal mines with existing twisted-pair cables and Ethernet switches, or use fiber optic Ethernet to exchange local area networks. The safety monitoring of coal mines has also gradually entered the all-IP networked field during the construction and installation phase.
Conclusion
The goal of realizing the safety production of coal mines is inseparable from the construction of safety precautions in mining areas. However, in the special monitoring environment of mining areas, the implementation of safety equipment must meet the explosion-proof requirements. Coal mine explosion-proof requirements should be the common basic conditions for all six coal mine safety systems. However, due to environmental changes in coal mines, it is difficult to fully control them. Therefore, only the construction and installation methods and conditions of the video surveillance system can be continuously improved, so that the conditions for explosion protection can be successfully achieved. Restricted to play a stronger monitoring performance.
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