| SYMPTOM |
CAUSE |
CORRECTION |
| Low
tool life caused by abrasive
Wear. Chip curl decreases
without burning; smoke or
steam begins or increases;
catering or rapid flank
or primary wear occurs |
Lack
of lubrication at cutting
edge of tool allows mechanical
abrasion between tool and
work piece. |
Select
fluid with better lubricating
qualities. Increase concentrations
on water miscible fluids.
Replace all old cutting
oils or water miscible.
Increase volume and pressure,
and direct into clearance
angles. |
| Low
tool life combined with
excessive heat. Pounding
in the cut; underside of
chip is rough and torn;
chip particles, burns or
heat checks on work-piece;
chips discolored; steam
smoke, or fire; heavy BUE
(built-up edge) or burns
on tool. |
Inadequate
cooling at cutting edge
of tool encourages tool
seizure or builds up. |
Select
fluid with higher cooling
capacity. Change from oil
to water miscible. Increase
flows or pressure; keep
tool flooded. Improve application
in clearance and back of
chip. |
| Low
tool life due to welding,
chipping and complete failure.
Heavy BUE on tool with particles
on part; chipped tool. |
Lace
of anti-weld properties
promotes the development
of a BUE type chip. The
unsTable BUE and fragments
leaving it are relatively
much harder than purest
material. This promotes
rapid wear through sliding
contact; and chipping by
pulling out some of the
base material when it leaves. |
Change
to a chemically active fluid,
preferably oil or one with
increased EP (extreme pressure)
or lubricating qualities.
Replace EP oils if indicated,
because of reduced chemical
activity. |
| Low
tool life due to chipping. |
Intermittent
or non-uniform cooling effects. |
Increase
flow or coverage; keep tool
flooded continuously. Improve
direction of application.
Change to fluid having lower
cooling properties. Remove
fluid on carbide tool. |
| Tool
seizure on drill, tap, reamer.
Tool sticks, breaks. |
Excessive
thermal expansion due to
inadequate lubrication of
rubbing surfaces |
Select
fluid, preferably oil, with
better EP and lubricating
qualities. Improve volume,
pressure, and direction
of fluid application. Check
for dilution of fluid. Increase
concentration of water miscible
fluids if necessary. |
| Surface
finish poor-rough, smeared,
torn, marred, discolored. |
Lack
of lubrication. Chip interference. |
Select
fluid with better lubricating
qualities to reduce BUE.
Check for dilution of fluid. |
| |
|
Improve
volume, pressure, and direction
to move chips out of cut
area. Improve filtration
to remove particles. |
| Out
of tolerance parts. |
Non-uniform
or inadequate cooling |
Keep
tool and work piece continuously
flooded. Maintain fluid
at constant temperature.
Check or dilution of fluid. |
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