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Honor
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Contact
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09
2023-02
Oil drill pipe-the advantages of the outer flat drill pipe.
Oil drill pipe-the advantages of the outer flat drill pipe.
2023-02-09
08
2022-12
08
2022-12
Production and harm of coal mine gas and coal dust
Production and harm of coal mine gas and coal dust
2022-12-08
08
2022-12
Common sense of coal mine safety-underground climatic conditions
Downhole climatic conditions
2022-12-08
08
2022-12
Common sense of coal mine safety-maximum allowable concentration of harmful gases in mines
The main harmful gases in the underground air are carbon monoxide, carbon dioxide, hydrogen sulfide, sulfur dioxide, Nitrogen dioxide, ammonia, methane and hydrogen, etc.
2022-12-08
23
2022-11
Common sense of coal mine safety -- basic knowledge of ventilation
Common sense of coal mine safety -- basic knowledge of ventilation
2022-11-23
23
2022-11
Common sense of coal mine safety -- how to use isolated self-rescuer
Common sense of coal mine safety -- how to use isolated self-rescuer
2022-11-23
23
2022-11
Common sense of coal mine safety-instructions for entering the well
Common sense of coal mine safety-instructions for entering the well
2022-11-23
23
2022-11
