| 摘要 |
PURPOSE:To execute efficient spark erosion, by causing a spark machining liquid containing water as the main constituent and a surface active agent, to have a cloud point and by heating the liquid above the cloud point after its use to solidify the surface active agent to recover it. CONSTITUTION:A spark machining liquid, which contains water as the main constituent blended with a surface active agent such as polyethylene glycol and hydrocarbon oil such as kerosene, is stored in a vessel 22 so that the liquid is supplied to a processing section in a spark machining vessel 1. After the liquid is used for the spark machining, chips 10 are removed from the liquid by precipitation in a sedimentation vessel 5 and the liquid is then sent to a heating vessel 7, in which the liquid is mixed with an adhering substance such as magnetic powder and stirred and heated above the cloud point previously provided for the liquid, so that the surface active agent is recovered as a precipitate 11. The recovered surface active agent is returned to the vessel 22 by a pump 18 and used again. |
