Owner's manual

ManualsBrandsSandvik Coromant ManualsMetalworkingThreading

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Thermal cracks

• Temperature variations from varying

cutting  uid supply or intermittent

machining leading to small cracks

perpendicular to the cutting edge,

insert frittering and poor surface

 nish

• Apply cutting  uid in large amounts,

or not at all

• Reduce cutting speed

Crater wear

• Excessive wear causing a weakened

edge

• Cutting edge breakthrough on the

trailing edge leading to poor surface

 nish

• Reduce speed to reduce tempera-

ture

• Reduce feed

Problem Cause Solution

Plastic deformation of edge, depres-

sion or  ank impression, leading to

poor chip control, poor surface

 nish and insert breakage.

• Cutting temperature and pressure

too high

Plastic deformation

• Reduce cutting speed

• Reduce feed