4 troubleshooting, Troubleshooting, Thread turning – Sandvik Coromant Threading User Manual

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4. Troubleshooting

Careful observation of the insert/cutting edge after machining can
help to optimize results regarding tool life, thread quality and cut-
ting speed. Use this list of causes and solutions to different forms
of insert wear as a reference for successful threading.

Problem

Plastic deformation

Cause

Solution

• Excessive temperature in cutting

zone

• Inadequate supply of coolant

• Wrong grade

Starts as plastic
deformation (A).

Leads to edge chip-
ping (B)

• Reduce the cutting speed, increase

the number of infeeds

• Reduce the largest infeed depth,

check the diameter before threading

• Improve coolant supply

• Choose a grade with better resis-

tance to plastic deformation

Rapid fl ank wear

•

Highly abrasive material

• Cutting speed too high

• Infeed depths too shallow

• Insert is above centre line

• Choose a more wear resistant grade

• Reduce cutting speed

• Reduce number of infeeds

• Adjust to correct centre height

Thread turning