Discussion on underground tunnel lighting

The underground tunnel lighting discusses the method of Yu Zhaofeng calculation and the specific content of cable laying, and proposes three effective measures to improve the lighting level.

+6: A mine lighting, especially whether the underground lighting is good, not only has a great impact on improving coal mine labor productivity and ensuring coal quality, but also plays an important role in reducing personal accidents and maintaining the health of workers.

Nowadays, heavy-duty fast coal mining machinery is increasing, and the underground space is narrow. If the lighting is insufficient, the headlights are only worn by the headlights, and the beams are only collected in a small circle. It is impossible for the miners to use their side vision to detect and react in time. Precautionary signals and symbols before the danger comes, take emergency measures to ensure personal safety; plus the glare of the miner's lamp, affect each other, extremely unfavorable.

The cost of the renovation of the case is relatively large, but it can be piloted and then implemented step by step.

3.2 Improve the control measures of the heating network After the heating metering and charging, the user can adjust the indoor temperature according to his own needs: This adjustment is to adjust the heat supply by adjusting the flow rate of the radiator.

When many users adjust the flow, the flow and heat supply of the entire heating network will change.

In order to ensure that the heat supply of each user is sufficient to minimize the running cost, the following two control schemes are proposed for the hot network adjustment method.

Option 1, water supply constant pressure control.

Select a point on the hot water supply line as the pressure control point, and keep the pressure at that point constant during operation. For example, when the user adjusts to increase the flow rate of the heat network, the pressure at the pressure control point must decrease. The rotation speed of the circulating water pump of the high heat network causes the pressure at this point to rise again to the original set value, thereby keeping the pressure of the pressure control point unchanged.

Option 2, supply and return water pressure difference control.

The pressure difference between the supply and return water on one of the heating network is used as the differential pressure control point, so that the pressure difference between the supply and return water at that point is always constant.

For example, when the user increases the heat, the pressure drop of the user system becomes smaller, and the pressure difference of the differential pressure control point is inevitably decreased. At this time, it is necessary to increase the rotation speed of the circulating water pump of the heat network, so that the pressure difference at the point rises again to the original setting. The value is such that the differential pressure of the differential pressure control point is kept constant.

3.3 Establishing a sound pricing method The metering and charging according to the household heat meter has the advantages of accurate measurement, fairness and reasonableness.

However, simply relying on the hot M meter to charge the user is unreasonable, because heat is a commodity that is different from water, electricity, and gas.

The rooms of the same area have different heat consumption due to different floors and different plane positions, and even vary greatly. Therefore, heat meter measurement can only be used as a parameter for billing, and cannot be the sole basis. In the actual billing, the calorie value correction should be performed for the rooms in different parts. The correction content should include floor correction, enclosure structure correction and orientation correction.

In order to formulate a reasonable price of heat, the cost of the hot price should be correctly calculated so that the price of the hot product can correctly reflect the value of the hot commodity and enable the user to accept it. The determination of the hot price requires consideration of two aspects of energy costs, fixed expenses and floating expenses.

Fixed expenses refer to expenses that are not directly related to heat production M, that is, expenses that must be paid in the absence of production, such as land use, equipment depreciation, maintenance management, and employee wages.

This part of the cost is not changed by the user's use or deactivation of energy, and the amount of consumption, and should be shared according to the building area occupied by the user. Floating expenses vary with heat production. The more heat is generated, the greater the floating expenses, such as fuel consumption, electricity consumption, water consumption, waste disposal, and overtime pay for employees. This part of the cost must be shared according to the actual heat used by the heat meter.

4 Conclusion The implementation of heating household measurement and charging is a key factor in the management of workers' housing to adapt to the market economy and enter a benign cycle. It is also an important part of energy conservation and improvement of the living environment of employees.

To this end, we should do a good job in the propaganda work of heating metering and charging, introduce specific measures and related policies for household charging, and formulate fair and reasonable hot prices to mobilize the enthusiasm of employees to participate.

At the same time, in order to reduce energy consumption and reduce costs, the transformation of indoor and outdoor heating pipe networks should be done to ensure the smooth implementation of national policies and regulations on household metering and charging.

Shanxi construction roadway name unit power/W*nT2 mining and excavation working face 5 main transportation roadway 12 å³’ room 12 well bottom yard 6-8 auxiliary roadway 1 illuminance standard of roadway lighting and distance between lamps can be shown in Table 2. Table 2 roadway lighting Illumination standard installation location lamp distance / m15W fluorescent lamp 60W100W incandescent lamp mining and preparation roadway working face 3546 mining area parking lot 3546 main transportation roadway 12 181525 bottom hole yard and main stone door 6 ~ good mine lighting, under the condition of ensuring safety According to the needs of coal production and staff life, physiological and health requirements, technical and economic rationality and possibility, the lighting is suitable for coal mine characteristics, safe, reliable, flexible and economical. In terms of quantity, the illuminance level is required to be appropriate, and it is convenient to control and adjust to meet the needs of various places with production links and the same place at different times.

In terms of quality, the uniformity of illumination is required, the spatial brightness distribution is reasonable, and the brightness ratio of the target and the background (especially the working surface) is appropriate, glare can be avoided, and good light color is obtained.

In this way, it is required to use a light source with high luminous efficiency, long life, suitable light color, economical durability and reliability; it is required to be equipped with lamps that are safe, light, efficient, inexpensive, well-distributed, interchangeable, and easy to maintain. In particular, explosion-proof luminaires require economical and rational use of environmental conditions to configure luminaires, and use lighting design and installation and maintenance methods suitable for different locations in mines.

With the development of the coal industry, the requirements for mine lighting are also increasing: the mechanization of mining, especially the comprehensive mechanization, requires changing the state of the past work surface by the miner's lamp alone; the linkage and automation of transportation and the accompanying transport speed The improvement requires no strong glare and flash in the roadway and improves the color of light; the remote monitoring and control of the production process, the increasing number of tests in the underground and the adoption of industrial television all require higher illumination levels and improved lighting quality. Miners are required to consider the lack of infrared rays in mine lighting and the adaptation of the light and shade of the upper and lower mines.

Reasonable electrical lighting is of great significance to downhole roadways because there is no natural light source in the downhole roadway. Practice has proved that in the coal mine production process, when the lighting is set on the working face, the labor productivity can be increased by 15%-25%, thereby reducing the cost of raw coal. Good illumination enables workers to better complete the selection work, reducing the ash content in the coal by 2% to 4%, and improving the quality of coal. In addition, it can alleviate workers' visual fatigue, improve working conditions, and strengthen the maintenance of electromechanical equipment due to the possibility of strengthening the inspection of roof and roadway brackets, which can play a significant role in preventing accidents.

1 Illumination standard and calculation method Illuminance is the main indicator to measure the quality of lighting. The illumination of mine lighting is related to the safety of coal mine production, the improvement of labor productivity, the guarantee of product quality and the health of staff. According to the regulations of coal mine safety regulations, there must be sufficient lighting in the following locations: electromechanical diverticulum, dispatching room, garage, gunpowder warehouse, health station, waiting room, signal station, etc.; use the roadway of the locomotive, the concentrated tape that also serves as the sidewalk Conveyor roadway, winch lane of lifters and winch lanes for alternate use of lifting materials and pedestrians; intersection of main roadway (excluding return airway) and mining yard; dedicated walkway from ground to underground; comprehensive mechanized coal mining surface.

Since the illuminance on the plane is inversely proportional to the square of the distance of the light source, the illuminance of each point of the illuminated surface is often different. The downhole reflectivity is as low as 〖%3%. The roughness and irregularity of various surfaces in the well make the reflectivity change with the angle of observation of the human eye and the human eye. When the human eye turns from a brighter plane to a darker plane, the human eye changes from a brighter plane to a darker plane. It takes a certain period of time to adapt, which makes the human eye easy to fatigue. Therefore, when calculating downhole lighting, proper uniformity should be considered. The so-called illuminance uniformity is the ratio of the minimum illuminance at the work site to the highest illuminance. There are generally three methods for calculating the lighting of underground tunnels that are not less than 0.1: point algorithm, luminous flux calculation method and comprehensive index method. Use a simple comprehensive index method at the site.

Downhole roadways generally require horizontal illumination, and vertical illumination is only required when it is required to ensure a certain illumination on the work surface.

Taking into account the requirements of coal mine technical operation regulations, as well as the width, length, temperature and safe transportation of roadway, the calculation results are shown in Table 1. Table 1 Roadway lighting requirements 2 Cable laying Downhole wellsite lighting power supply, generally from the central substation, The lighting transformer of each workplace is powered. The secondary voltage of the transformer is 127 V. Different types of cables are applied in the lighting line depending on the application and installation location. The fixed circuit of the bottom hole yard and the main transportation roadway generally uses armored cable or PVC or rubber cable. When using a through-light (such as KB-60-2), the cable should be laid along the top of the roadway. When using terminal lighting such as KB-60-1, the cable should be laid on the side of the roadway and the lighting should be illuminated by a three-way junction box.

The lighting cable uses a three-core armored cable or a four-core rubber cable. A two-core armored cable or a three-core rubber cable can be used for the branch line that introduces the lighting. The grounding of the illuminator housing is made of lead and metal armor of the armored cable, and the rubber cable is grounded.

Due to the installation conditions, the lighting trunk cable does not exceed 10nW and the section of the branch cable leading to the illumination is 1.5 mm22.5mm2. The lighting of the mining and mining face of the mining area is specified only by non-combustible rubber cable connection.

In short, the best way to improve underground lighting is to improve the overall lighting level, first of all to increase the illuminance or brightness, followed by the reasonable distribution of the luminaire, and thirdly to improve the environmental and reflective surface of the object, such as whitening of the roadway, equipment paint A color with a high reflectance.

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