|
| US4387776 | 24 Nov 1980 | 14 Jun 1983 | | Well case driving anvil |
| US4415047 | 24 Nov 1980 | 15 Nov 1983 | | Downhole case driving apparatus for impact drills |
| US5503224 | 14 Feb 1995 | 2 Apr 1996 | Big Iron Drilling Ltd. | Casing drive apparatus |
| US5590726 | 5 Jun 1995 | 7 Jan 1997 | | Drilling apparatus |
| US5839519 | 8 Nov 1996 | 24 Nov 1998 | Sandvik AB | Methods and apparatus for attaching a casing to a drill bit in overburden drilling equipment |
| US5957224 | 12 Aug 1997 | 28 Sep 1999 | | Double bit assembly and method of using the same |
| US6106200 | 12 May 1999 | 22 Aug 2000 | Techmo Entwicklungs-und Vertriebs GmbH ALWAG" Tunnelausbau Gesellschaft m.b.H. | Process and device for simultaneously drilling and lining a hole |
| US7416036 | 14 Apr 2006 | 26 Aug 2008 | Baker Hughes Incorporated | Latchable reaming bit |
| US7673706 | 30 Mar 2006 | 9 Mar 2010 | Sandvik Intellectual Property AB | Down-the-hole hammer with pilot and method of enlarging a hole |