Test report
| Item | Reference cermet grade | KT20 (Koves) |
|---|---|---|
| Workpiece and operation | ||
| Workpiece material | 40Cr alloy steel (AISI 5140) | |
| Cut type | Continuous cut | |
| Machined surface | Black skin (as-forged) | |
| Operation | OD + facing | |
| Test machine | CNC horizontal lathe | |
| Coolant | Coolant (flood) | |
| Tools compared — only the grade was changed | ||
| Tool manufacturer | Japanese cermet maker | Koves (KOVES) |
| Insert model | VBMT11T304 | VBMT11T304 |
| Chipbreaker | HQ | HQ |
| Insert grade | Reference cermet grade | KT20 |
| Cutting conditions — identical for both tools | ||
| Spindle speed S | 1800 min⁻¹ | |
| Table feed F | 110 mm/min | |
| Depth of cut ap | 0.2 mm | |
| Result | ||
| Tool life (parts/edge) | 300 | 300 |
| Outcome | Tool life equal — test stopped before the wear limit | |
Result and comparison basis
The KT20 edge produced 300 parts per edge, matching the reference grade part-for-part at identical cutting data. The customer stopped the test before the wear limit was reached, so parity here is a conservative floor rather than a ceiling — the Koves edge was not run to failure.
Matching an established Japanese cermet grade in the same pocket, on the same machine, is the baseline result plants look for when qualifying a second source.
Comparison basis: the cermet grade the customer was running before the test, anonymised as “Reference cermet grade”. Insert model, chipbreaker and all cutting data are shown in full.
Related series
- VBMT Positive Cermet Turning Inserts — M Grade — 11 models
Comparative data from a Koves customer cutting test. Competitor grades are anonymised as reference grades. Results depend on workpiece, machine and setup; validate on your own production before adopting parameters.
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