Sealed and lubricated rotary cone drill bit having improved seal protection
US5513711A · kind A · utility
Inventor
Key dates
| Filing date | Aug 31, 1994 |
| Grant date | May 7, 1996 |
| Priority date | — |
| Expiry date | Aug 31, 2014 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B10/25
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A rotary cone drill bit (10) for forming a borehole includes a support arm-cutter assembly (26). A support arm (28) is integrally formed with the drill bit's body (22) with a spindle (30) machined integral thereto. The assembly (26) includes a cutter (12) with a cavity (34) for receiving the spindle (30). An inner seal gland (44) is formed between the spindle (30) and a wall (42) of the cavity (34). An elastomeric seal (46) is disposed in the inner seal gland (44) to form a first fluid barrier between. An outer seal gland (50) is formed between the spindle (30) and the cavity wall (42) and between the inner seal gland (44) and the borehole. A ring (56) is disposed in the outer seal gland (50) to rotate with the cutter (12). The ring (56) has a peripheral hole (58) therethrough. A gas conduit (60) is disposed within the support arm (28) for directing a flow of a gas, such as air, into the outer seal gland (50). From the outer seal gland (50), the gas is directed through the hole (58) in the ring (56) and exits into the borehole to form high velocity jets of air to dean a mating surface between the arm (28) and the cutter (12) preventing borehole debris from entering the inner seal g…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.