F - MECHANICAL ENGINEERING
F27 - FURNACES
F27D - DETAILS OR ACCESSORIES OF FURNACES, KILNS, OVENS, OR RETORTS, IN SO FAR AS THEY ARE OF KINDS OCCURRING IN MORE THAN ONE KIND OF FURNACE
Y - NEW / CROSS SECTIONAL TECHNOLOGIES
Y10 - TECHNICAL SUBJECTS COVERED BY FORMER USPC
Y10S - TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
F - MECHANICAL ENGINEERING
F27 - FURNACES
F27D - DETAILS OR ACCESSORIES OF FURNACES, KILNS, OVENS, OR RETORTS, IN SO FAR AS THEY ARE OF KINDS OCCURRING IN MORE THAN ONE KIND OF FURNACE
F27D2003/0038 - {comprising shakers}
Y - NEW / CROSS SECTIONAL TECHNOLOGIES
Y10 - TECHNICAL SUBJECTS COVERED BY FORMER USPC
Y10S - TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
Y10S266/905 - Refractory metal-extracting means
C - CHEMISTRY
C04 - CEMENTS
C04B - LIME, MAGNESIA
C04B35/057 - based on calcium oxide
F - MECHANICAL ENGINEERING
F27 - FURNACES
F27B - FURNACES, KILNS, OVENS, OR RETORTS IN GENERAL
F27B14/10 - Crucibles
F - MECHANICAL ENGINEERING
F27 - FURNACES
F27D - DETAILS OR ACCESSORIES OF FURNACES, KILNS, OVENS, OR RETORTS, IN SO FAR AS THEY ARE OF KINDS OCCURRING IN MORE THAN ONE KIND OF FURNACE
F27D1/1626 - {Making linings by compacting a refractory mass in the space defined by a backing mould or pattern and the furnace wall}
C - CHEMISTRY
C22 - METALLURGY
C22B - PRODUCTION AND REFINING OF METALS
C22B60/0213 - {by dry processes}