Page 422 - THREADING CATALOG

USER GUIDE
THREAD DRILLING Problem • poor clamping of the chuck • check the clamping. use hydraulic clamping

Cause
Solution
chuck, maxin power chuck or a shrink system.
• workpiece movement
• increase workpiece chucking force.
• check drill type and drilling depth, cooling
• wrong drill
system and workpiece material.
• check cooling lubricant. increase coolant
• insufficient coolant
pressure. in the case of external coolant supply,
improve jet direction and add cooling jets.
• unsuitable cutting conditions
• worn out drill center point (chisel)
• regrind cutting edge.

• use pecking cycle.
• insufficient chip evacuation • reduce feed.

drill breakage
• check the clamping and adaptation.
• poor clamping of the chuck use hydraulic clamping chuck, maxin
power chuck or a shrink system.
• workpiece movement • increase workpiece chucking force.
• check drill type and drilling depth, cooling system
• wrong drill
and workpiece material. possibly use longer drill.
• check cooling lubricant. increase coolant
• insufficient coolant pressure. in the case of external coolant supply,
chipping on the improve jet direction and add cooling jets.
cutting corners • unsuitable cutting conditions • check cutting parameters, and possibly reduce feed.
• worn out or broken cutting corner • replace drill or regrind cutting edge.

• unsuitable cutting conditions • reduce feed by 30-50% during exit.

• worn out drill • replace drill.
burrs on exit
Ra • unsuitable cutting conditions • adjust feed to improve chip flow.

• make sure that the drill’s runout is
• large runout
within 0.02 mm (radial & axial).
• chip jamming • reduce cutting speed.

• increase coolant pressure.
rough surface finish
• apply pecking procedure.
• make sure that the drill runout is
• large runout
within 0.02 mm (radial & axial).
• check and improve drill and
• poor stability
workpiece clamping rigidity.
• when drilling hard materials or sloped surfaces,
• rough application
deviation of hole reduce feed by 30-50% during entrance.
position • use a short pilot drill with 140° point angle.

ISCAR
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