First, dressing
The earth's crust is made up of rocks, which are a collection of minerals. When the content of a certain component or certain components in the rock is economically and advantageously extracted and utilized by current production t…
Tungsten metal tin ores minerals are wolframite, cassiterite small amount, scheel…
What if I have three tons? The Doosan forklift is even stronger!
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The tectonic stress is the stress caused by the movement of the crustal structure in the rock mass. Tectonic stress includes the stress generated in the underground rock during the occurrence of geological formations; and the residual geological tectonic movements remaining inside the rock …
Introduction: Safety valves play a safety role in the system. When the system pressure exceeds the specified value, the safety valve opens, and part of the gas/fluid in the system is discharged into the atmosphere/outside of the pipeline, so that the syst…
This regulation specifies the beneficiation plant steel core belt conveyor contents and requ…
Omen and measurement of large area pressure of the top plate
1. omen
The harbinger of large-area pressure is mainly manifested by the increase of the frequency and sound of the sound of the roof fracture; the coal gang has obvious pressure an…
The first time to press: the top of the working face caused by the first instability of the old top, called the first time of the old top.
The first step of the pressure step: the distance from the opening of the eye to the initial pressure of the working face is called the ini…
Figure 11-1 shows the stress distribution in the surrounding rock and pillar of the inclined deposit obtained by finite element calculation.
(1) Stress concentration occurs in the upper disc corner and the lower disc corner of the mining space (mine);
(2) In the stage pillar…
The mining face bracket is mainly composed of a combination of beams and columns. According to the cooperation relationship between the pillar and the top beam, the mining face bracket can be divided into two categories, namely, a single bracket and a hydraulic bracket. Face bracket made