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The New Era of NTK CBN Grades

High CBN content provides excellent wear resistance and long tool life
Features
  • Uncoated CBN grade : BK310 / BK320 / BK350
Uncoated CBN BK310 / BK320

High CBN content provides stable wear resistance in high-speed turning of Gray cast iron and sintered alloys.
Fine particle size provides excellent edge sharpness and is effective in suppressing burrs.

BK310 Competitor

Gray cast iron (FC300)
vc = 500m/min 1600 SFM , f = 0.3mm/rev .012 IPR , ap = 0.3mm .012” DOC ,
After processing 3Km 120000”

Uncoated CBN BK350

General-purpose material with excellent wear resistance and chipping resistance compared to
ductile cast iron for continuous to heavy interrupted use.

BK350 Competitor

Ductile cast iron (FCD600)
vc = 300m/min 1000 SFM , f = 0.1mm/rev .004 IPR , ap = 0.2mm .008” DOC ,
After processing 4Km 160000”

Application area for turning

Cast iron – Finishing

BK310 and BK320 cutting conditions

- - - Scroll the table - - -
●1st Recommendation 〇2nd Recommendation
Grade Cutting speed Feed DOC Coolant
(m/min) (SFM) (mm/rev) (IPR) (mm) (inch) DRY WET
BK310 BK320 400 – 1200 1300 – 3900 up to 0.5 .020 up to 2.0 .089

Sintered powder metal

BK310 cutting conditions

- - - Scroll the table - - -
●1st Recommendation
〇2nd Recommendation
Grade Cutting speed Feed DOC Coolant
(m/min) (SFM) (mm/rev) (IPR) (mm) (inch) DRY WET
BK310 40 – 300 130 – 980 up to 0.5 .020 up to 0.5 .020

Ductile cast iron – Finishing

BK350 cutting conditions

- - - Scroll the table - - -
●1st Recommendation
〇2nd Recommendation
Grade Cutting speed Feed DOC Coolant
(m/min) (SFM) (mm/rev) (IPR) (mm) (inch) DRY WET
BK350 100 – 450 330 – 1480 up to 0.2 .008 up to 1.0 .040
Cutting edge preparation according to processing purposes

← Sharpness

Toughness →

Agriculture Parts
Insert :
TNGA 160408 PH T01020
Material :
Gray cast iron (FC250)
Cutting speed :
700 m/min 2300 SFM
Feed :
0.1 mm/rev .004 IPR
DOC :
0.2 mm .008 inch
Coolant :
WET
BK310
150 pcs / corner
Competitor’s CBN
100 pcs / corner

Conventional CBN would experience chattering at the corners and reach the end of their tool life, but BK310 maintains its sharpness and achieved 1.5 times longer tool life.

Machinery parts
Insert :
CNGA 120408 PQ T01020
Material :
Ductile cast iron (FCD450)
Cutting speed :
400 m/min 1300 SFM
Feed :
0.05 mm/rev .002 IPR
DOC :
0.5 mm .020 inch
Coolant :
WET
BK350
100 pcs / corner
Competitor’s CBN
50 pcs / corner

Conventional CBN develop burrs in the hole and reach the end of its tool life, but BK350 maintains its sharpness and achieves twice the tool life.

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