安全高效开采
safe and high-efficient exploitation
good safety and efficiency
煤与瓦斯安全高效共采
safe and high-efficient exploitation of coal and g
safe and high-efficient exploitation of gas and co
5tX-Y高安全葫芦
5 t X-Y high security hoist
安全高电压接头
safe high voltage connector
安全效益
safe performance
benifit from safe operation
safety benefit
safety benefits
safety benifit
safety effect
safety profit
垂直安全高度
vertical height of safe mining
等效安全
Equivalent Level of Safety