| 摘要 |
<p>A magnetic change speed gearbox 16 for use in a downhole assembly having a shaft supported by a gas bearing 28, 30. The downhole assembly may be one comprising a motor 14 driving a compressor 12 by way of a step-up magnetic gearbox 16 or one comprising a gas turbine driving a pump by way of a step-down magnetic gearbox.</p> |
