| PROBLEMES |
CAUSES |
SOLUTIONS |
|
|
|
| CHIPPING
OR BREAKAGE |
-Poor
chip evacuation due to insufficient coolant pressure and/or
volume |
Increase
coolant flow |
|
|
| -Deflection |
Reduce
overhang |
|
|
| -Misalignment |
Check
concentricity not to exceed +/- .005 tir |
|
| -Speed
too slow, feed too light |
Increase
speed and/or feed |
|
|
| -Wrong
chipbreaker geometry |
Use
stronger chipbreaker(3P) |
|
|
|
| CORNER
OF INSIDE INSERT CHIPS AT CENTER |
-High
cutting force at center of drill |
Use
tougher grade or uncoated grade in inside position |
|
|
|
| LOUD,
ROUGH CUTTING |
-Excessive
thrust force |
Reduce
feed, increase speed |
|
|
|
| -Re-cutting
chip |
Increase
coolant flow |
|
|
|
| LONG
UNBROKEN CHIP |
-Insuffi.
coolant pressure and volume |
Increase
coolant flow |
|
|
| -Feed
rate too light |
Increase
feed |
|
|
| -Wrong
chipbreaker geometry |
Check
setup and part rigidity |
|
|
|
| CHATTER |
-Vibration |
Check
setup and part rigidity |
|
|
| -Poor
chip control |
Increase
coolant flow |
|
|
| -Drill
not properly seated in holder |
Check
set-up |
|
|
|
| HOLE
SIZE TOO LARGE |
-Drill
misaligned |
Correct
misalignment |
|
|
|
| FRACTURING
OF DRILL |
-Improper
seating of inserts |
Check
insert seating |
|
|
| -Unstable
spindle |
Use
rigid machine |
|
|
| -Insufficient
horsepower |
Reduce
feed or change machines |
|
|
| -Excessive
thrust force |
Reduce
feed |
|
|
|
| SHORT
TOOL LIFE |
-Excessive
insert wear |
Lower
cutting speed or change grade |
|
|
|
| -Lack
of rigidity |
Check
set-up and spindle |
|
|
| -Improper
coolant |
Check
type of coolant and mixture |
