Carbide drill for one-shot machining of castings with IT8 grade hole accuracy!
Achieves excellent machining accuracy with „drill edge” + „4 special reamer edges”
IT8 grade hole finish in one shot
Excellent surface finish accuracy
Long tool life with suitable coating for high hardness materials
Amazing facts!
── Introducing ideas and technologies ──
The BJGF drill consists of 2 drill edges and 4 burnishing reamer edges.
High rigidity and multiple reamer edges enable ‘high-precision machining’. The back-jet coolant supply provides excellent cooling performance and chip evacuation for ‘excellent surface roughness’ . The multi-layer coating is adopted for ‘long lifetime’. All of these make it possible to finish casted metal workpieces in one-shot.
IT8 grade hole diameter accuracy
Good!
[Processing conditions]
JIS FC250 / EN-GJL-250 / DIN GG50 / WNr 0.6025
ø8 Vc = 50 m/min, f = 0.1 mm/rev
Excellent surface roughness
Good!
[Processing conditions]
JIS FC250 / EN-GJL-250 / DIN GG50 / WNr 0.6025
ø8 Vc = 50 m/min, f = 0.1 mm/rev
This is the point!
The role of the cutting edge is divided by function
Excellent!
One-shot machining with 2 drill edges and 4 special reamer edges
Coolant applied directly to the reamer edges
Development / product concept
“Current status and challenges”
- One-shot drills have been developed to improve productivity in the machining of cast iron parts, but the problem was that the surface roughness of the finish machining could not be achieved due to the formation of a built-up edge (welding) on the reamer edge.
“Development points”
- Cooling of the cutting edge and chip evacuation is improved by using a back-jet style coolant channel. The built-up edge formation on the reamer edge is suppressed to ensure excellent surface finish roughness. Furthermore, the use of a multi-layer coating for high-hardness materials suppresses edge wear and increases service lifetime.
Processing example
Tools used
BJGF drill
Machining work
Test piece
Work material
JIS FC250 / EN-GJL-250 / DIN GG50 / WNr 0.6025
Tool diameter
ø8 mm
Cutting conditions
Cutting speed: Vc = 40 m/min
Feed: f = 0.1 mm/rev
Accuracy
required
Processing requirement:
- hole ø8 -0.025/-0.035
- surface roughness Ra 3.2 µm
Tool:
- Drill ø7.3 mm + Reamer ø8 mm
Machining hole diameter
Surface roughness
Roundness variation
Product specification
- Tool specification
Tool name
BJGF drill
Target process
Knock hole/high precision hole
Setting diameter
ø6 ~ ø20 mm
Standard conditions
Cutting speed: Vc = 50 m/min or less
Feed: f = 0.1 ~ 0.2 mm/rev
Machining accuracy
Hole diameter: IT8 grade
Surface roughness: Rz <12.5 (Ra <3.2)
Roundness: 10 µm
- Example of applicable work
