with rotary drilling heads having variable diameter

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CPC
E21D9/0874

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Parent Industries

EFIXED CONSTRUCTIONS E21Mining E21DSHAFTS TUNNELS GALLERIES LARGE UNDERGROUND CHAMBERS E21D9/00Tunnels or galleries, with or without linings Methods or apparatus for making thereof Layout of tunnels or galleries

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E21D9/0874with rotary drilling heads having variable diameter

Industries

Patents Grantslast 30 patents

Information Patent Grant
Tunnel boring machine
- Patent number 10,539,016
- Issue date Jan 21, 2020
- XCMG-KAIGONG HEAVY INDUSTRY NANJING CO., LTD
- Yanqi Su
- E21 - EARTH DRILLING MINING
Information Patent Grant
Shield tunneling with optional section and machine
- Patent number 4,998,776
- Issue date Mar 12, 1991
- Zaidan Hohjin Doboku Kenkyu Center
- Shohei Chida
- E21 - EARTH DRILLING MINING
Information Patent Grant
Control system for synchronous rotation of cutter heads, for use in...
- Patent number 4,939,431
- Issue date Jul 3, 1990
- Ishikawajima-Harima Kukogyo K.K.
- Hidetsugu Yamazaki
- E21 - EARTH DRILLING MINING

Patents Applicationslast 30 patents

Information Patent Application
TUNNEL BORING MACHINE
- Publication number 20190264563
- Publication date Aug 29, 2019
- XCMG-KAIGONG HEAVY INDUSTRY NANJING CO., LTD.
- Yanqi SU
- E21 - EARTH DRILLING MINING