How to judge chip removal and bit wear through the cutting condition of deep hole drill? Mainly through the following six points:
(1) Cutting conditions cannot be observed directly. Chip removal and bit wear can be judged only by sound, chip, machine load, oil pressure and other parameters.
(2) Cutting heat is not easy to spread out.
(3) It is difficult to remove chips. If the chips are blocked, the drill bit will be damaged.
(4) Due to the long, poor rigidity and easy vibration of the drill pipe, the hole axis is easy to deviate, affecting the machining accuracy and production efficiency.
(5) The coaxiality of the center lines of the main shaft, tool guide sleeve, arbor support sleeve and workpiece support sleeve shall meet the requirements; the cutting fluid system shall be unblocked and normal; there shall be no center hole on the machining end face of the workpiece and drilling on the inclined plane shall be avoided; the chip shape shall remain normal to avoid the generation of straight strip chips; the through hole shall be machined at a higher speed, and the speed shall be reduced or reduced when the drill bit is about to be drilled through Shut down to prevent damage to the drill bit.
(6) Cutting oil for deep hole machining: a large amount of cutting heat will be generated in the process of deep hole machining, which is not easy to diffuse, and sufficient cutting fluid needs to be supplied to lubricate and cool the cutting tools. Generally, 1:100 emulsion or extreme pressure emulsion is selected; extreme pressure emulsion or high concentration extreme pressure emulsion is selected when high machining accuracy, surface quality or machining toughness materials are required, and the kinematic viscosity of cutting oil is usually high 10 ~ 20cm2 / S (40 ℃) is selected, and the flow rate of cutting oil is 15 ~ 18m / S; cutting oil with low viscosity is selected for small machining diameter; for deep hole machining requiring high precision, the ratio of cutting oil can be 40% extreme pressure sulfide oil, 40% kerosene and 20% chlorinated paraffin.
