Ground wellhole dedicated protective pipe for gas extraction of mining-induced area
US10883320B2 · kind B2 · utility
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4References
8Claims
0Family size
Assignee
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Key dates
| Filing date | Jul 13, 2018 |
| Grant date | Jan 5, 2021 |
| Priority date | — |
| Expiry date | Jul 13, 2038 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B41/00
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A ground wellhole dedicated protective pipe, disposed inside a ground wellhole for gas extraction of a mining-induced area, includes a casing, and a chain inside the casing and slidable relative to the casing. The chain includes a chain formed by a plurality of chain drums through serial connection, and a detachable connecting piece connecting between chains. A plurality of air holes is opened in the chain drum along an axial direction of the chain drum.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.