What is boom coal mining and what is long arm mining

It is a longwall According to the arrangement of the working face, it is divided into a trending longwall and an inclined longwall coal mining, and the longwall refers to the length of the working face greater than 100 meters.

It refers to the coal mining method with a working face length of more than 100 meters.

Wall coal mining method, the length of the mining face is longer; There are roadways for transportation, ventilation and pedestrians at both ends of the working face; When the mining work is advancing forward, it must be continuously supported; The goaf should be dealt with in a timely manner according to a certain method as the working face advances; The transportation direction of the coal in the mining face is parallel to the coal wall of the working face.

First of all, there are two kinds of longwalls, one is the longwall and the other is the inclined longwall, the former is arranged along the trend, and the latter is arranged along the inclination, and the direction is different.

Then say backward coal mining: this definition is relative, that is, the direction of mining in the working face and the early stage of the formation of the working face, the excavation direction of the face machine and the wind roadway, on the contrary, the backward mining, all the way back to the position where the excavation began, this mining method is called backward mining.

(1) The inclined longwall coal mining method is suitable for gently inclined thin and medium-thick coal seams, as well as mining areas that cannot be arranged to the longwall working face damaged by faults or magmatic rocks. The inclined longwall working face is divided into two types: inclined mining and inclined mining according to the direction of advancement. If the coal quality is hard or the roof is drenched with water, it is generally advisable to use inclined mining; If the thickness of the coal seam is large, the coal is soft and easy to flake, and it is advisable to use inclined mining.

The mining face should generally be advanced in the direction of the roadway, that is, the coal seam above the horizontal roadway is mined in the slope mode, and the coal seam below the horizontal roadway is mined in the slope mode, so as to facilitate the ventilation of the working face and the maintenance of the roadway. In mines with suitable geological conditions, this method is compared with the strike-trending longwall coal mining method.

The advantages are: simple roadway layout, low roadway excavation and maintenance costs, and fast production. According to the comparative data of Soviet mines, under the same mine geological conditions, inclined longwall mining is reduced by 10 20% compared with the length of the roadway leading to longwall mining, and the construction period of large mines can be shortened by 1 2 years.

The transportation system and ventilation system are relatively simple, and the technical and economic effect of the mining face is good. It is easy to realize the equal length working face, and reduces the process of adding and disassembling the self-moving hydraulic support and lengthening or shortening the conveyor due to the change of the working face length. The disadvantage of this method is that the distance of inclined roadways is long, which makes auxiliary transportation and pedestrians more difficult.

It has been popularized in China since the 70s. It is suitable for coal seams with an inclination angle of less than 12°, and can be extended to coal seams of 15° and 18° for mechanical mining and blast mining. In foreign countries, the coal seam with an inclination angle of 33° has been successfully mined by using the dipping fully mechanized mining face.

2) Strike longwall coal mining method refers to the working face is arranged along the inclined direction of the coal seam, and the return air roadway and the transportation roadway are arranged along the strike above and below the mining face respectively, so as to form the ventilation, transportation and pedestrian passage between the mining face and the roadway in the mining area, and the mining is carried back from the boundary of the mining area to the uphill (or downhill) direction of the mining area along the direction of the coal seam strike.

There are two directions of advancement of the mining face: backward type, which advances from the boundary of the mining area to the uphill (or stone gate) of the mining area; Forward, from the mining area up the hill (or stone gate) to the boundary of the mining area. Most of China's mining areas use backward mining.

In the fully mechanized mining area, in order to reduce the long-distance transfer of fully mechanized mining equipment, some adopt mixed type, that is, after the upper section mining face is used to advance mining to the boundary of the mining area, the fully mechanized mining equipment is moved to the opening and cutting eye of the lower section boundary, and the backward mining is used.

There are many classification methods of coal mining methods, and coal mining methods are usually divided into two categories: wall system and column system according to the characteristics of coal mining process and mine pressure control.

To sum up, it can basically be divided into two major systems: wall type and column type.

1) Wall coal mining method. According to the different thickness of the coal seam, for the thin and medium-thick coal seams, the single longwall coal mining method with full thickness is generally adopted; For thick coal seams, it is generally divided into several medium-thickness layers, and the layered longwall coal mining method is adopted. According to the relationship between the advancing direction of the mining face and the trend of the coal seam, it can be divided into two types: the trending longwall coal mining method and the inclined longwall coal mining method.

2) Pillar coal mining method. The pillar coal mining method is divided into room type and room pillar type. The essence of the room-type and room-and-pillar coal mining method is to excavate some coal houses in the coal seam, and the coal houses are connected by a connecting lane.

Mining is carried out in the coal house, the coal pillar can be left without mining, or after the coal house is mined, and then the coal pillar is returned, the former is called the room type coal mining method, the latter is called the room pillar coal mining method, these two coal mining methods are rarely used in our country.

2) Gently inclined and inclined coal seam single longwall coal mining method.

The gently inclined and inclined coal seams adopt the working face of the single longwall coal mining method, and the mining process mainly includes three types: blast mining, general mining (high-grade general mining) and fully mechanized mining. When selecting the working face mining process, it should be considered in combination with the mine geological conditions, equipment conditions, technical conditions, technical management level and coal mining system.

1) Shelling process. The mining process of the blasting face includes six major processes: coal breaking, coal loading, coal transportation, transfer conveyor, working face support and roof management.

2) Ordinary mechanized coal mining process. Ordinary mechanized coal mining is to use a shallow section drum shearer to drop and load coal, use a bendable scraper conveyor to transport coal, and use friction metal pillars (or single hydraulic pillars) and hinged top beams to support the cantilever support. ic gz3m]\x1e

3) Mining process of fully mechanized mining face. Comprehensive mechanized coal mining refers to the entire production process of coal mining, including coal falling, coal loading, coal transportation, support, roof management, etc., all of which are mechanized.

3) Comprehensive mechanized top coal mining technology.

China's top coal mining mainly refers to longwall comprehensive mechanized top coal mining (hereinafter referred to as comprehensive mining).The essence of fully mechanized mining is to arrange a longwall working face along the bottom of the coal seam, carry out mining in a comprehensive mechanized way, and make full use of the mine pressure (supplemented by artificial loosening method in special circumstances) to make the top coal above the working face crushed, and put it down behind (or above) the support, and transport the released coal out of the working face with a rear conveyor.