PURPOSE: An indexable drill is provided to discharge of the cut chips is provided to guide the discharge of cut chips by spraying coolant with maintaining the pressure of coolant. CONSTITUTION: An indexable drill(100) comprises first and second ribs(121,122), first and second flutes(131,132), first and second coolant holes, first, second, and third middle coolant holes, and first, second, and third coolant outlets(152,162a,162b). The first, and second ribs are spirally formed on the upper part of a shank(110). The first and second flutes discharge cutting chips. The first coolant hole is formed inside the shank with first diameter. The second coolant hole is formed with the second diameter larger than the first diameter. The first middle coolant hole has the different curvature with the first and second flutes. The first coolant outlet sprays a part of coolant on a first section(143) of the upper part of the first rib. The second coolant outlet sprays a part of coolant to an inner cutting insert(210).
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