Molten metal inclusion sensor probes
US6566853B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 27, 2001 |
| Grant date | May 20, 2003 |
| Priority date | — |
| Expiry date | Jul 31, 2021 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2015/0053
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Molten metal inclusion sensor probes have a sensing passage through which the molten metal passes, while direct current passes through the passage between two electrodes. The passage of an inclusion through the passage changes the resistance in the path, resulting in a pulse indicating its size, and enabling the number of particles in a sample to be counted. Previously the passage has been cylindrical, with or without a conical entrance, or of randomly smoothed profile produced by melting the probe material. High levels of background noise make pulse detection difficult, and operation is improved by the passage decreasing smoothly in cross-section in the flow direction, preferably with a parabolic or elliptical profile, and preferably with the exit of the same profile. The wall surface is formed to a smoothness of better than 1.016 micrometers (40 microinches), preferably 0.254 micrometers (10 microinches), permitting pre-determination of the optimum testing and conditioning currents required.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.