Apparatus for automatically determining certain characteristics of cement
US4849175A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 4, 1988 |
| Grant date | Jul 18, 1989 |
| Priority date | — |
| Expiry date | Jan 4, 2008 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N33/383
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method and apparatus for automatically measuring the grain fineness, the gypsum content and the limestone content of a cement sample. A first fraction of the sample is loaded by a vibrating hopper into a crucible resting on an automatic scale. This crucible is handled sequentially by tongs on two revolving arms carried on slidable vertical shafts. The circular paths of the arms intersect at a point just above the scale. Motions of the arms and of the tongs are controlled by a programming unit. The weighed sample is poured into a sieve and the weight of oversize grains is automatically related to the sample weight. Gypsum is measured by heating a second fraction of the sample at 1000.degree. C. plus in an oxygen stream, Fe powder being added from a fixed hopper. The crucible is raised into an induction furnace. Released SO.sub.2 is bubbled in a titration cell to which potassium iodate is gradually added by a burette giving an automatic read-out of the SO.sub.3 (gypsum) titration. Limestone is also measured by heating a third fraction of the sample to release CO.sub.2, and measuring the weight increase of a column, filled with NaOH which absorbs the released CO.sub.2, which is plac…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.