الصفحة الرئيسية > Term: long-pillar work
long-pillar work
Coal winning in three stages in underground mining. First, large pillars are left as the face is advanced by means of drives. Second, parallel drives connect these drives and form large blocks. Finally, the pillars so formed are mined.
- قسم من أقسام الكلام: noun
- المجال / النطاق: التعدين
- الفئة: تعدين عام; Mineral mining
- Government Agency: USBM
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المنشئ
- ed.young
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(Milwaukee, United States)