Longwall mining

Plan of longwall mine before conveyors, hoist is at the center of the central pillar.

Oklahoma advancing longwall mine c. 1917; arrows show airflowWest Virginia retreating longwall mine c. 1917

Longwall mining is a form of underground coal mining where a long wall of coal is mined in a single slice (typically 0.6 – 1.0 m thick). The longwall panel (the block of coal that is being mined) is typically 3 – 4 km long and 250 – 400 m wide.

单词	Armored face conveyor
释义	Armored face conveyor 英语百科 Longwall mining Longwall mining is a form of underground coal mining where a long wall of coal is mined in a single slice (typically 0.6 – 1.0 m thick). The longwall panel (the block of coal that is being mined) is typically 3 – 4 km long and 250 – 400 m wide.
随便看	xanthagenate的意思 xanthaline的意思 xanthalysin的意思 xantham的意思 xanthamide的意思 xanthamides的意思 xanthan的意思 Xanthandrus comtus的意思 xanthane的意思 xanthan gel的意思 Xanthan gum的意思 xanthan gums的意思 xanthanol的意思 xanthanolide的意思 xanthanolides的意思 xanthan的意思 xanthate的意思 xanthate acid的意思 xanthate,alkyl dithiocarbonate的意思 xanthate的意思 xanthated cotton的意思 xanthated gel的意思 xanthated micelle的意思 xanthate group的意思 xanthate group distribution的意思

Armored face conveyor

Longwall mining