... and equipments.heat treatment equipment:4.8x8.6m,5.5mX10m large size coal gas trolley furnace, φ3mX6.5m furnace of different ... quenching for all kinds of shaft no longer than 16m, large size surpporting roll, rolling mill roll. etcRing parts: the hardening ... within 6500mm) gear: the hardening and tempering, surface quenching for large size gear(modulus over 5 and diameter within 10m.) all kinds ...