Patent ID: 7011017

Claim:
A compactor used for compacting sludge containing abrasive grains and small-particle metallic residue, comprising: a first cylindrical body including an expansion formed at an inner periphery of a first end portion thereof, said expansion having a greater inner circumferential dimension than that of a second end portion thereof, and for accommodating in said first cylindrical body a material to be compacted; a second cylindrical body replaceably mounted in the expansion of the first cylindrical body to form a compaction chamber jointly with the first cylindrical body, and having an inner peripheral surface flush with that of the first cylindrical body; a pressing mechanism for pressing material to be compacted toward said first end of the compaction chamber; and a gate mechanism for opening or closing said first end of the compaction chamber; wherein an axial length of the second cylindrical body is substantially not less than ⅗ times the axial length of a compact obtained by compacting material to be compacted, and wherein the abrasive grains have a hardness of not less than 1950 Knoop Hardness.