|
| US4102401 | 6 Sep 1977 | 25 Jul 1978 | Exxon Production Research Company | Well treatment fluid diversion with low density ball sealers |
| US4139060 | 14 Nov 1977 | 13 Feb 1979 | Exxon Production Research Company | Selective wellbore isolation using buoyant ball sealers |
| US4160482 | 12 Jun 1978 | 10 Jul 1979 | Exxon Production Research Company | Ball sealer diversion of matrix rate treatments of a well |
| US4187909 | 16 Nov 1977 | 12 Feb 1980 | Exxon Production Research Company | Method and apparatus for placing buoyant ball sealers |
| US4194561 | 16 Nov 1977 | 25 Mar 1980 | Exxon Production Research Company | Placement apparatus and method for low density ball sealers |
| US4195690 | 14 Ago 1978 | 1 Abr 1980 | Exxon Production Research Company | Method for placing ball sealers onto casing perforations |
| US4421167 | 30 Ago 1982 | 20 Dic 1983 | Exxon Production Research Co. | Method of controlling displacement of propping agent in fracturing treatments |
| US4488599 | 22 Jul 1983 | 18 Dic 1984 | Exxon Production Research Co. | Method of controlling displacement of propping agent in fracturing treatments |
| US4702316 | 3 Ene 1986 | 27 Oct 1987 | Mobil Oil Corporation | Injectivity profile in steam injection wells via ball sealers |
| US4702318 | 9 Abr 1986 | 27 Oct 1987 | Mobil Oil Corporation | Injectivity profile in CO.sub.2 injection wells via ball sealers |
| US4881599 | 29 Mar 1988 | 21 Nov 1989 | Petroleo Brasileiro S.A. - Petrobras | Mechanical system for diversion in the acidizing treatment of oil formations |
