Longwall mining with chain pillar recovery
US3999804A · kind A · utility
14Cited by
2References
10Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Mar 8, 1976 |
| Grant date | Dec 28, 1976 |
| Priority date | — |
| Expiry date | Mar 8, 1996 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21C41/18
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
In a longwall mining system, a work face extends between parallel sets of multiple head- and tailgate entries, adjacent entries of each set being separated by rows of chain pillars. Lengths of a headgate entry immediately adjacent the longwall panel and the pillar breakthroughs to the next headgate entry are progressively pump packed in advance of the longwall face with a coherent thixotropic roof supporting material. As the longwall face is mined, a bidirectional shearing machine cuts through the roof supporting material and the chain pillars, which are then removed in a continuous operation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.