Page 218 - ISCAR(HOLE_MAKING_CATALOG_65)

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.

216 ISCAR