IPC 6 English version  Class B28
SECTION B– PERFORMING OPERATIONS; TRANSPORTING

B 28

WORKING CEMENT, CLAY, OR STONE

B 28 B

SHAPING CLAY OR OTHER CERAMIC COMPOSITIONS, SLAG OR MIXTURES CONTAINING CEMENTITIOUS MATERIAL, e.g. PLASTER (foundry moulding B 22 C; working stone or stone-like material B 28 D; shaping of substances in a plastic state, in general B 29 C; making layered products not composed wholly of these substances B 32 B; shaping in situ, see the relevant classes of section E)

B 28 C

PREPARING CLAY; PRODUCING MIXTURES CONTAINING CLAY OR CEMENTITIOUS MATERIAL, e.g. PLASTER (preparing material for foundry moulds B 22 C 5/00)

B 28 D

WORKING STONE OR STONE-LIKE MATERIALS (machinery for, or methods of, mining or quarrying E 21 C)

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