Page 218 - ISCAR(HOLE_MAKING_CATALOG_65)
P. 218

USER GUIDE
      DEEP DRILLING - BTA SYSTEM



          Chip Form General Information

              Chip form in deep hole drilling                                      Table 1
              Chip form plays a key role in STS (Single tube system)
              and DTS (Double tube system) while large-volume and
              high-pressure coolant do so as well. Because chips are                              Central  Intermediate  Peripheral
              removed through the tube with coolant, proper chip
              formation is essential for smooth and steady evacuation.

              Chip formation                                           110
              Chip formation is affected by multiple factors, such
              as workpiece material, chipbreaker geometry, cutting
              speed, feed, type of coolant, and coolant temperature.   90
              Suitable chip formation depends on cutting operation   Cutting speed: Vc (m/min)
              but is controllable by changing the cutting conditions.  70
              How to decide the chip form
              Generally the chip length should be 3 - 4 times          50
              its width, but tends to be longer with difficult-to-cut
              materials. In this case, chip evacuation can be                0.10        0.15       0.20
              improved by making the chips thinner, which is     Condition          Feed: f (mm/rev)
              normally done by reducing the feed rate.          From left to right in each box the order is central, intermediate and
              The graph below shows chip formation for different   peripheral chip.
              cutting speeds and feeds. Short chips are created by
              reducing the cutting speed or increasing the feed.


























































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