The cutting grooves of the CD-S center drill have a proper spiral groove shape, which can smooth the chip flow direction of the drilling head and the hole repair part, so that it can be discharged smoothly, so that the tool damage can be avoided due to chip blockage. In addition, the length of drill bit is properly shortened by design and machining. And the combination of drilling head and hole finishing part is made of R type joint. Therefore, it can improve machining efficiency and reduce damage during cutting and elimination.
(2)The CE-S high spiral center drill has a spiral groove and a longer groove, which is higher than the general center drill CD-S, especially for the processing of the viscous material.
·Center drill material：HSS
·Center hole angle：60°
·Bit groove shape：CD-SLow spiral groove CE-SHigh spiral groove
·Suitable cutting material：
[CD-S] tensile strength 750~1100N/mm2 alloy steel, tool steel, Quenched and tempered steel and so on...