Nuclear magnetic resonance tool with magnetostrictive noise compensation
US6326785A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jul 18, 2000 |
| Grant date | Dec 4, 2001 |
| Priority date | — |
| Expiry date | Jul 18, 2020 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01V3/32
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An NMR logging apparatus and method are provided including an antenna having compensation for magnetostrictive ringing. The antenna comprises at least one inductive winding and a core having a first portion having positive magnetostriction in the presence of a radio frequency magnetic field, and a second portion having negative magnetostriction in the presence of the radio frequency magnetic field. The positive and negative portions may be tiles shaped as polygonal cylinders arranged with alternating positive and negative tiles forming at least one layer of a matrix, or the portions may be constructed using ferrite powder fixed in epoxy and shaped in polygonal cylinders.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.