Common sense of underground electricity safety in coal mine

Job requirements: 1, physical examination after entering the mine; 2. Training to obtain safety qualification certificate; 3. Training to obtain special operation certificate (underground electrician); 4. Sign a mentoring contract and so on, guided by experienced old workers; 5. It is best to have a mechanical and electrical background, constantly study theory, and gradually integrate with practice until you are qualified.

Operating rules for underground maintenance electrician 1. Operation preparation 1. Check whether the materials, accessories, tools, test instruments and other items required for maintenance are complete and in good condition. 2, stop sending, must be carried out in accordance with the provisions of the power operation ticket and timely contact with mine scheduling.

Second, the normal operation of 1, before operation, must check the gas concentration within 20 meters of electrical equipment maintenance. When the gas concentration is lower than 1%, ordinary portable measuring instruments can be used to check, discharge, ground and operate the electrical equipment.

2, before maintenance of underground electrical equipment, must cut off the front power switch, experience electricity to confirm that the power supply has been cut off, and then discharge, hanging ground wire, personnel must touch the electrical equipment. 3. It is forbidden to maintain electrical equipment with electricity, and the power-off switch must be locked and hung with the sign "No power transmission when someone is working".

4. In the system controlled by the same feed switch, when two or more points work at the same time, the sign of "No power transmission when someone is working" should be hung separately, and a general manager should be set up to contact and coordinate related work. After work, before power transmission is resumed, it must be checked by special personnel. After all the work is completed, the power transmission can be started after the power failure sign is eliminated.

It is forbidden to send electricity at the appointed time. 5. When stopping high-voltage electrical equipment, the operator must wear insulating gloves and high-voltage insulating boots and stand on an insulating platform to operate.

6. The quality of electrical equipment after maintenance must meet the requirements. 7, in strict accordance with the original design drawings for maintenance, shall not be arbitrarily changed, the relevant parameters should meet the technical requirements.

8, all kinds of protection of electrical equipment must be complete and meet the technical requirements. Three, after the completion of the finishing touches, the working controller shall conduct a detailed inspection and acceptance of the maintenance work, dismantle the grounding wire and remove the power outage board, check the tools, and report to the relevant personnel for confirmation, then restore the normal power supply, and conduct a trial run of the maintenance equipment and fill in the maintenance records.

2. Iron ore safety knowledge.

Iron ore mining mainly includes: (1) open-pit mining; ② Underground mining; (3) Mineral processing and treatment technology, including three parts: 1, ore crushing equipment and technology, jaw crusher, impact crusher and magnetite beneficiation technology; 2, grinding equipment and technology, lattice ball mill, cone ball mill, the third generation of sand machine; 3. Separation technology and equipment, magnetic separation technology, high gradient magnetic separator and flotation technology, BSK flotation machine; (4) Environmental protection.

Hui Yu introduces you to the common sense of underground iron ore safety:

1, receive three-level safety education before taking up the post to improve safety awareness and safety technical quality.

2, understand whether the enterprise legal production, license is complete.

3, underground whether there are more than two exports, mine it is forbidden to one-eyed well, want to have a second channel.

4, lifting equipment should be anti-falling, anti-overwinding device.

5, take a look at whether there is mechanical ventilation underground.

6, see if there are any underground drainage pumps, at least two or more.

7, take a look at the underground voltage, whether it is low voltage, especially the working face voltage.

8. Is there a ladder for people to climb up the shaft, and can people escape?

3. How to ensure the safety of electricity consumption under the mine?

The specific measures to ensure the safety of underground electricity use are: (1) Correct selection, use and installation of electrical equipment and cable lines according to the allowable temperature rise conditions.

(2) Set leakage protection and cut off the dangerous leakage network in time to ensure personal safety and production safety. (3) Select the rating of electrical equipment reasonably to meet the needs of equipment and ensure the safe operation of electrical equipment.

(4) Strengthen daily operation and maintenance, and require the personnel on duty to pay attention to the operation of electrical appliances at all times and pay attention to daily inspection and maintenance. (5) In order to ensure the installation quality of electrical equipment, cable laying should be carried out in strict accordance with the safety requirements of China coal mine.

(6) Transformer oil shall be sampled, tested and inspected regularly. When the insulation performance drops, it can be filtered and regenerated, and it can only be used after passing the withstand voltage test.

(7) Underground lighting must have a protective cover or use explosion-proof fluorescent lamps.

4. What measures are there to ensure the safe use of electricity underground?

Measures to ensure the safe use of electricity underground mainly include: (1) Correct selection, use and installation of electrical equipment and cable lines according to the allowable temperature rise conditions; (2) Set up leakage protection and cut off the dangerous leakage network in time to ensure personal and production safety; (3) Select the rating of electrical equipment reasonably to meet the needs of equipment and ensure the safe operation of electrical equipment; (4) Strengthen daily operation and maintenance, and require the personnel on duty to pay attention to the operation of electrical appliances at all times and pay attention to daily inspection and maintenance; (5) Ensure the installation quality of electrical equipment and lay cables in strict accordance with regulations; (6) Transformer oil pressure should be sampled, tested and checked regularly.

When the insulation performance declines, it can be filtered and regenerated, and it can only be used after passing the withstand voltage test; Underground lighting must have a protective cover or use explosion-proof fluorescent lamps.

5. What are the working conditions of underground power supply and distribution and the measures to ensure the safe use of electricity underground?

Working conditions in coal mines are very unfavorable to electrical safety.

The main reason is: (1) the space of underground power consumption place is narrow. (2) Under the influence of blasting and roof pressure, the spalling and coal blocks often fall off, and electrical equipment and cables are vulnerable to mechanical damage such as smashing, bumping and squeezing.

(3) The underground environment is humid, and some places are drenched with water. Without moisture-proof measures, it is easy to damage the insulation performance of electrical equipment and cause leakage or short circuit accidents. (4) There is gas and coal dust in the underground air, and the arc generated by switch, spark generated by leakage, arc generated by short circuit and other fire sources can make explosive gas or coal dust explode.

(5) Underground electromechanical equipment is bulky, frequently started, and the load changes greatly, which is easy to cause overload. (6) The workplace changes frequently and the equipment moves frequently.

Due to the above factors, underground safe power supply is of great significance. Therefore, safety measures must be taken to ensure safe production.

The current measures are: (1) Correct selection, use and installation of electrical equipment and cable lines according to the allowable temperature rise conditions. (2) Set leakage protection and cut off the dangerous leakage network in time to ensure personal and production safety.

(3) Select the rating of electrical equipment reasonably to meet the needs of equipment and ensure the safe operation of electrical equipment. (4) Strengthen daily operation and maintenance, and require the personnel on duty to pay attention to the operation of electrical appliances at all times, and pay attention to daily inspection and maintenance.

(5) In order to ensure the installation quality of electrical equipment, cable laying should be carried out in strict accordance with the requirements of the regulations. (6) Transformer oil shall be sampled, tested and inspected regularly.

When the insulation performance declines, it can be filtered and regenerated, and it can only be used after passing the withstand voltage test. (7) Underground lighting must have a protective cover or use explosion-proof fluorescent lamps.

6. What are the potential safety hazards of underground electrical equipment?

The management of underground electrical equipment and power supply in mining area is a key point of coal mine electromechanical work at present.

Connecting with the author's working experience, this paper analyzes how to do well the management of underground electrical equipment from aspects of perfecting the management organization, grasping the explosion-proof performance, strengthening the on-site management, and improving the safety protection performance. Statistics of underground accidents show that many major accidents are caused by electricity.

A considerable part of the reasons are caused by human factors: either the system is not strict, or the management is not good, or there are rules that are not followed and careless. Therefore, how to take various measures to strengthen the management of electrical equipment and put an end to electrical accidents is a major topic in the current electromechanical work of coal mines.

1 Perfect management organization Underground electrical equipment can be roughly divided into four categories: equipment, cables, safety protection devices and small electrical appliances. According to the system, professional organizations such as equipment management, explosion-proof inspection, low-voltage electrical management, small electrical appliances and cable management have been established for centralized and unified management.

The equipment management group is responsible for the configuration and maintenance management of all kinds of mechanical and electrical equipment in the whole mine; The explosion-proof inspection team and the low-voltage electrical management team are divided into two or three transformer rooms according to the regional division of labor. All low-voltage equipment supplied by the transformer room is under their overall management, and they are responsible for the inspection and maintenance of electrical equipment, the management of three major protections, the supervision and implementation of power supply in mining areas, the inspection of explosion-proof performance, and the approval of power supply and electricity consumption in various mining areas. The small electrical group is responsible for receiving, maintaining, dispatching and managing the bell, button, tee, signal line and power box of 127V system; The cable management group is responsible for the repair, distribution and deployment of power rubber-sheathed cables. Therefore, every equipment, every cable and every small electrical appliance underground has corresponding professional management team full-time personnel who are responsible for management respectively.

Clear division of labor, there is no mutual buck passing. At the same time, managers have the right to inspect and accept maintenance units, inspect and supervise users and cut off power supply, make suggestions and stop handing over equipment, and put forward opinions on the use of equipment.

Each professional management group carries out system management in the form of drawings, cards, boards and accounts (cards), and the equipment management is mainly based on microcomputer management. On the ground, you can see the use and flow of underground electrical equipment at a glance.

While strengthening professional management, the mine has improved the group management organization. Each mine auxiliary unit is equipped with a deputy section chief of electromechanical department. After passing the technical training examination, the maintenance monitor of each district will be the network operator for equipment management and explosion-proof inspection in this area. The responsibility system of mine electromechanical management personnel was implemented, the weekly meeting system of electromechanical district chief and maintenance squad leader was established, and the combination of professional management and group management was implemented, so that information was available from the top, reports were made from the bottom and notifications were made from the top.

Members of various management networks are distributed in various workplaces, and problems can be found in time. It has formed an assessment and supervision system with the mechanical and electrical mine manager, deputy mechanical and electrical mine manager, section chief, engineer, technician, "four specialized management groups", mine mechanical and electrical district head and maintenance monitor as the backbone.

Pay close attention to explosion protection of electrical equipment. First of all, strictly control the "three customs": ① maintenance. After the maintenance of flameproof electrical equipment, the platform must be qualified and explosion-proof.

After each equipment is put into the well, it should be disassembled and inspected, and the vulnerable equipment should be replaced. The explosion-proof surface is polished, phosphatized and oiled. If the shell is deformed, it should be reshaped, the exterior should be painted with antirust paint, and the inner cavity should be painted with arc-resistant paint. Measure the clearance, effective length and parameters of each explosion-proof surface; Replace the cracked terminal; The operation and suction mechanism should be flexible and reliable; Wait a minute. Then power on for load test. After various electrical tests and quality inspections, it is found that the equipment is safe and qualified, and the parts are complete and complete. Record the maintenance and acceptance, register the technical parameters and maintenance contents, and put a label in each equipment to indicate the maintenance personnel and main technical parameters.

It is convenient to find the responsible personnel in time and accurately after the problems appear on site, and the responsibility of maintenance personnel is strengthened. (2) acceptance.

Technicians and explosion-proof inspectors are responsible for the acceptance of the electrical equipment after overhaul, re-conduct the power-on test, determine the explosion-proof technical parameters, make acceptance records, fill in the acceptance personnel and acceptance date on the internal label, and complete the above procedures before warehousing. The mechanical and electrical department shall organize the finance, planning, auditing, enterprise management and related users for the newly arrived equipment or outsourced maintenance equipment in No.4 Mine, and * * * check and put them in the warehouse, and record them in the account to build a card.

(3) Into the well. When the electrical equipment is powered on again before entering the well, a certificate of entering the well with an "explosion-proof electrical equipment acceptance form" and an "explosion-proof qualified sign" must be issued.

The wellhead hook operator is responsible for the verification and custody of this certificate, and may not go down without a license, otherwise the hook operator shall be held accountable. The special management team shall regularly check the "downhole qualification certificate" with the hook operator.

3 Strengthening on-site management inspection There are three main forms of on-site inspection: ① Professional managers regularly inspect the equipment, cables and small appliances running Xin, and comprehensively inspect the safety protection devices at least twice a week. For the problems found in the inspection, in addition to informing the maintenance personnel of the unit to solve them on the spot, a "notice of potential safety hazards" will be issued after going down the well.

After power failure, major problems (such as fire and connector disconnection) will be solved immediately. After the inspection, fill in the inspection daily report and send it to the competent technician and section chief for signature, so as to grasp the situation in time, make overall arrangements and focus on handling.

(2) the mine organization 3 times a month irregular mechanical and electrical equipment in good condition. During inspection, the number of explosion-proof electrical equipment generally accounts for more than 40% of the equipment used.

Check not only the explosion-proof equipment, but also the three major protections, small appliances, cables and industrial hygiene, as well as the suspension of cables and signal wires, and link the inspection results with economic benefits. (3) The equipment management network member and explosion-proof inspection network member of each employer shall conduct self-inspection.

They patrol and check the running equipment every day. Individual work areas have also deployed 1~2 maintenance personnel, who are specialized in on-site equipment integrity inspection, rectification and cable hanging.

We should actively explore and produce mines. The dynamic evaluation method of on-site quality is organized and implemented by the electromechanical department. The inspected units are determined by drawing lots every month, and the best and worst units in the mining face are comprehensively inspected and evaluated, rewarding the excellent and punishing the poor, which greatly improves the on-site management level of the mining face and promotes the underground electrical equipment to be always in a qualified state.

4 to improve the safety protection performance of underground power supply, not only the parts of the equipment itself should be intact, but also various safety protection devices should be paid attention to.

7. Coal mine safety knowledge

1, protect all kinds of safety production facilities, devices, safety signs and measuring signs. It is strictly prohibited to use equipment that is not used by oneself without authorization, and unlicensed personnel shall not engage in special operations.

2, not alone in the underground shooting and operation, more are not allowed to work alone in remote areas and dangerous areas.

3, into the well homework personnel should grasp the blasting time, place, warning range, must leave the danger zone before blasting.

4. Abide by the operating rules of safety technology and the safety management regulations of each post, obey the supervision and guidance, do not operate illegally or take risks, and report the accident immediately.

If there is a sudden power failure, you should immediately stop working and retreat to a safe place.

6, before work should be knocked to help ask the top, at work to check the supporting situation at any time, found that the roof, help loose or fall off, should immediately avoid or stand to a safe place to clean up. When there are signs that seriously endanger personal safety in the workplace, you must evacuate the dangerous area quickly, report and deal with it in time, and set up warning or signal signs.

7, strict labor discipline, are not allowed to be in the underground fire to keep warm, make a noise, play, sleep and string post. Smoking is not allowed underground.

8, need to have a rest in the underground, should choose the roof in good condition, support in good condition, do not interfere with the work, do not interfere with driving, well ventilated safe place. Don't rest in front of closed walls or dead ends. These places are poorly ventilated and easy to accumulate harmful gases.

8. Coal miners' safety knowledge

First, enter the well.

1. Coal mine is a high-risk industry. Eat well, sleep well and rest well before entering the well. Never drink alcohol to keep energetic.

2, open flame and static electricity will lead to gas explosion and fire, can't wear chemical fiber clothes and carry cigarettes and ignition items under the well.

3. Before entering the well, you should wear miner's lamp, safety helmet and self-rescuer, and you can't work under the well without proper equipment or equipment.

4. When carrying sharp tools, please cover the sheath to prevent injury.

5. Through the pre-shift meeting, you can understand the safety production situation in the workplace, make clear the safety precautions, master the preventive measures and ensure the safety of the work, so you should attend the pre-shift meeting on time.

6, consciously abide by the "into the well physical examination system", obey the command, queue up into the well, accept the medical examination.

9. Coal mine common sense knowledge

Safe power supply in coal mine underground

I. Direct current and alternating current

(1) direct current

Direct current: If the direction of current remains unchanged, it is called direct current. Such as miner's lamp, battery electric locomotive, stringing electric locomotive, etc.

② alternating current

Alternating current: The current whose direction and magnitude change periodically is called alternating current. Generally speaking, alternating current refers to sinusoidal alternating current. AC is divided into single-phase AC and three-phase AC.

1. If only sinusoidal alternating current flows through electrical equipment, this alternating current is called single-phase alternating current. For example, electric lights and bells use single-phase alternating current.

2. If three sinusoidal alternating currents flow in electrical equipment, and the maximum values of these three sinusoidal alternating currents are equal, only the time after zero value is 120 (expressed in geometric terms), such alternating currents are called three-phase alternating currents. For example, coal drills and scraper conveyors use three-phase alternating current.

Second, the classification of coal mine power users

Coal mine power users can be divided into three categories:

1. First-class users: those who cause personal injury or serious equipment damage due to sudden power failure and cause great economic losses to the enterprise are first-class users. Such as coal mine main ventilator, underground main drainage pump, auxiliary shaft hoist, etc. These users use two circuits from different power buses to supply power, and they should ensure to supply power to the power grid in normal or accident situations.

2. Second-class users: users who have greatly reduced production and suffered great economic losses due to sudden power failure. For example, centralized coal lifting equipment in coal mines, ground air compressors, mining substations, etc. Generally, this kind of users use double loop power supply or circular line power supply.

3. Three types of users: these users have no direct impact on production when power is suddenly cut off. For example, coal mine wellhead repair shops and public utilities electrical equipment.

Three, the mine power supply voltage level

According to the regulations, the voltage level selected by the mine power supply system is:

1, mine ground substation 35kV- substation voltage.

2. 10 kV or 6kv-underground high-voltage distribution point voltage and rated voltage of high-voltage motor.

3, 3 kV or 1 140v- rated voltage of electrical equipment in comprehensive mechanized coal mining face.

4660 V-Distribution voltage of underground low-voltage power grid.

5, 380 v-ground and small underground low-voltage power grid distribution voltage.

6, 220 v-ground and underground fresh air alleys lighting voltage.

7. 127v- Maximum rated voltage of lighting, hand-held electrical equipment, telephones and signaling devices.

8, 36v- the voltage of the underground equipment control circuit.

9, DC 250V, DC 550v overhead electric locomotive commonly used rated voltage.

Four, the safe use of electricity in coal mines

(a) it is strictly prohibited to live maintenance, relocation of electrical equipment.

Because of the narrow underground, humid air and water mist, the risk of electric shock is increased. Especially there are explosive substances such as gas and coal dust underground. If the electrical equipment (including cables and wires) is overhauled or moved with electricity, it is easy to get an electric shock or a short circuit accident, which may lead to electric sparks and gas and coal dust explosions. Before maintenance or relocation, the power supply must be cut off and tested with a test pen suitable for the power supply voltage. After checking that there is no electricity, you must check the gas. When the gas concentration in the roadway airflow is lower than 65438 0%, the conductor can discharge to the ground. When cutting off the power supply, all switch handles should be locked, and a warning sign "No power transmission when someone is working" should be hung. Only the person who performs this work has the right to remove this sign and transmit electricity.

(B) coal mine safety power supply "three noes, four haves, two neat, three complete and three adherences" content.

Common electrical accidents in coal mines mainly include short circuit, electric leakage, overload, open phase, lost explosion and personal electric shock. Other electrical accidents or dangers are mainly caused by these accidents. If the underground power supply of coal mine can achieve "three noes", "four haves", "two neat", "three complete" and "three persistences", the above-mentioned various electrical accidents can be prevented or not expanded. This is a summary of the experience and lessons of electrical accidents in coal mines for many years.

Three noes: no chicken feet, no sheep tail and no joints. These "three noes" are very effective measures to prevent short circuit, electric leakage and personal electric shock accidents.

Four: there are overcurrent and leakage protection devices, screws and spring washers, sealing rings and baffles, and grounding devices. These "four haves" are very effective in preventing short circuit, overload and leakage faults from expanding, preventing people from getting an electric shock and preventing fire.

Alignment: cables are hung neatly, and the equipment room is clean and tidy. This "two in one" is an effective measure to prevent electrical accidents caused by various cable and electrical equipment failures in the cave.

Sanquan: complete protective devices, complete insulation appliances and complete drawings and materials. These "three safeties" are important measures to prevent accidents such as electric shock, strengthen the management of electrical equipment and technology, correctly guide production and prevent various electrical accidents. With this "three all", when an electrical accident occurs, it can also be judged and handled correctly and quickly.

Persistence: Insist on the use of leak detection relay, insist on the use of coal electric drill, lighting and signal comprehensive protection, and insist on the use of gas and electricity and wind power locking. As long as the "three persistences" are achieved, not only personal electric shock accidents caused by electric leakage can be prevented, but also gas explosion accidents caused by electric leakage can be prevented.