1. Ore body dip angle - generally <35°~40° Most mines are less than 30°. The inclination angle of the ore body should not change much. When the inclination angle is >40°, the work of pillars, antimony ore, rock drilling is very difficult and very unsafe. .

2, the thickness of the ore body - generally <3 ~ 4 meters, more than <2 meters of ore body. When the ore body thickness is more than 4 meters, the support of the working face is extremely difficult, and the labor intensity of the workers is large.

3, direct top plate - should have a certain thickness, and should be easy to collapse. (It is ideal when the thickness of the top plate is ≥ 6 to 8 times the thickness of the ore body).

4, the bottom of the ore body - it is better to be flat, otherwise it will affect the antimony ore.

5, the size and continuity of the ore body - the size of the ore body is relatively large, but the continuity is better, which is conducive to the advancement of the longwall working face.

6. Require the surface and surrounding rock to allow for subsidence.

7. There is no limit to the stability of the ore.

(2) Main advantages and disadvantages

advantage:
1The roadway layout is simple

2 Large production capacity and high labor productivity;

3 can handle the gob in time

4 good ventilation;

5 It is possible to conduct sorting and hand picking (the waste rock is thrown into the gob);

6 Conducive to mechanization

Disadvantages:
1 Large wood consumption (consuming more than 10m ³ of wood per kiloton);

2 The labor intensity of the support work is large;

3 roof management is more complicated;

4 The mining process is more complicated;

5 When the geological structure of the deposit is more complicated, the safety is relatively poor;

(3) Research and improvement direction in the future;

(1) Further study and master the law of ground pressure activities and improve the management of topping;

(2) Studying pit wood substitutes to reduce wood consumption;

(3) Develop a new type of working surface transporting machinery; (There are many electric picks in foreign countries. When the mine descent angle is slow and the mine thickness is >2.5 m, the loose deposits of the bottom plate can be tested by the trackless equipment, which can be transported by the chain conveyor. Moving ore).

1) This 5 axis cnc router machine with 8 rotary axis is with removable table, so, when you cut and engrave the flat / 

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