Printed from Kezuriba (kezuriba.net/en/troubles/ream-breakage/)
Reamer breaks or seizes
Reaming Reaming
Check first
- Chip clogging
- Pilot hole is small, or the reaming allowance is small, increasing the burnishing torque
- Wear of the lead chamfer is large or uneven
Try first
- Increase the cutting fluid flow and pressure, and improve the filtration accuracy
- Reduce the cutting speed to limit peripheral wear
- If chip clogging is the cause, choose a reamer with different specifications
?Likely causes
- Chip cloggingAgreed by 2+ makers[1][2]
- Pilot hole is small, or the reaming allowance is small, increasing the burnishing torqueAgreed by 2+ makers[1][3]
- Back taper is small or the cylindrical land is wideOne maker[1]
- Feed is highOne maker[1]
- Wear of the lead chamfer is large or unevenAgreed by 2+ makers[1][3]
- Seizure from poor filtration or insufficient pressure of the cutting fluidOne maker[3]
- Pilot hole is bentOne maker[2]
✓Fixes
Cutting conditions
- Reduce the cutting speed to limit peripheral wearOne maker[3]
Tool
- If chip clogging is the cause, choose a reamer with different specificationsOne maker[2]
- Use a spiral flute reamer for through holes and a straight flute reamer for blind holesOne maker[1]
- Increase the lead angle to secure enlargement allowanceOne maker[3]
Coolant
- Increase the cutting fluid flow and pressure, and improve the filtration accuracyAgreed by 2+ makers[2][3]
Where sources differ: Sandvik states that a spiral flute is needed for through holes and a straight flute for blind holes.
↔Related problems
📚Sources
Causes and fixes are summarized in our own words from cutting-tool makers’ troubleshooting guides and technical data. “Agreed by 2+ makers” means two or more makers say the same thing.
- Sandvik Coromant — Troubleshooting for reaming sandvik.coromant.com
- OSG — Series No.35 Reamers, Table 6.1 Troubleshooting, pp. 30-31 osg.co.jp
- Tungaloy tungaloy.com