IPC Subgroup
E21D 5/012 Use of fluid-tight or anti-friction material on outside of, or between, lining layers
Introduced: September 1968
Last revised: January 2006
Full Title
Lining shafts; Linings therefor > Use of fluid-tight or anti-friction material on outside of, or between, lining layers
Classification Context
- Section:
- FIXED CONSTRUCTIONS
- Class:
- EARTH OR ROCK DRILLING; MINING
- Subclass:
- SHAFTS; TUNNELS; GALLERIES; LARGE UNDERGROUND CHAMBERS