drill bit life calculation
TRANSCRIPT
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DRILL BIT FATIGUE LIFE ESTIMATEFEA SIMULATION
REV A 12/11/17
D. BLANCHET
3B ASSOCIATES
23 ROCKY HILL RD.
BURLINGTON, MA 01803
781-272-7057
PREPARED FOR: I. TIMOSHENKO
0.375 DIA TOOL STEEL
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SOLIDWORKS MODEL INCLUDING SMALL DEFECT
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FEA REFINED MESH – 4 ADAPTIVE STEPSNEAR EXPECTED STRESS CONCENTRATIONS
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APPLIED BOUNDARY CONDITIONS
Fixed in chuck
Side loading components
From cutting
Reaction forces
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STATIC STRESS ANALYSIS – MAX BELOW FRACTUREMISALIGNMENT “WOBBLE” 0.0035 INCH
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DRILL WOBBLE .0035CAUSE OF ALTERNATING
TENSILE AND COMPRESSIVE
STRESSES – INDUCINGFATIGUE FAILURE
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FATIGUE LIFE S-N CURVE
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FATIGUE LIFEESTIMATEFROM FEA
AT 800 RPM
1.6E04/800 =20 MINUTES