GRINDING COOLANT SUPPLIER, GRINDING SYSTEM AND GRINDING METHOD

A grinding coolant supplier that is a device supplying a grinding coolant to a grinder (1) for grinding a machine part element provided with rollers, said grinding coolant supplier comprising: a grinding coolant preparation device (7) preparing a grinding coolant that is a liquid mixture consisting of a water-soluble stock solution of the coolant, a first modified water having an average water particle diameter of 80-150 nm inclusive and a second modified water having an average water particle diameter of 5 nm or more and less than 80 nm; and a grinding coolant feeding means (6) supplying the grinding coolant thus prepared to the grinder (1). 种磨削冷却液供给装置，其为向磨削机(1)供给磨削冷却液的装置，该磨削机将具有滚动体的机械部件的单元进行磨削，该磨削冷却液供给装置具备生成磨削冷却液的磨削冷却液生成装置(7)、以及将该生成出的磨削冷却液向前述磨削机(1)供给的磨削冷却液运送机构(6)，所述磨削冷却液是水溶性的冷却液原液、水颗粒的平均粒径为80nm以上且150nm以下的第1改性水、以及水颗粒的平均粒径为5nm以上且不足80nm的第2改性水的混合液。