Rotary drilling drill string stabilizer-cuttings grinder
US4373592A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 28, 1980 |
| Grant date | Feb 15, 1983 |
| Priority date | — |
| Expiry date | Nov 28, 2000 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B21/10
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
An arrangement for alleviating the problem of differential sticking of a drill string in rotary drilling of a highly deviated borehole by grinding and reducing the size of the cuttings generated by the drilling operation to enable the mud-return flow to better remove the cuttings from the wellbore. At least one full gage, rotating stabilizer-grinder is placed along the drill string at a selected point in the high angle section of the hole. In one embodiment, this stabilizer-grinder is constructed with an inner mandrel which is part of and rotates with the drill string and powers the first part of the grinder, and an outer mandrel which is free to rotate separately from the inner mandrel. The outer mandrel is full gage and fits against the borehole wall such that it remains stationary with respect thereto. The outer mandrel thus forms the second part of the grinder on which cuttings are broken and reduced in size. In another embodiment, a downhole turbine mud motor powers a grinder positioned just above the downhole drilling collars.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.