Каталог Dormer Pramet фрезерование 2021 - 2022 - страница 781

INSERT FRACTURE

↓ (H) grain has a great influence. (MT)CVD + PVD coating recommended. PVD

f ↓

Very important to reduce cutting force.

v ↑↓

It is about swarf control and vibration.

POOR SURFACE QUALITY

Description and cause: Corrective measures: Numerous causes depending on the workpiece material, cutting Use a finishing insert, or an insert with finishing segment conditons (feed rate and cutting speed), the condition of the cutting Use an insert with suitable cutting geometry edge, the extent and type of wear, and the condition and rigidity of the

• Reduce the feed rate

machine – tool – workpiece assembly.

• Adjust (usually increase) the cutting speed
• Incorrect tool chosen
• Use coolant or lubrication (MQL)
• Incorrect chip thickness
• Eliminate vibrations
• Incorrect cutting speed
• Use a tool with which the position of the individual inserts can be
• Coolant is needed

adjusted more accurately

• High feed rate
• Change the chip thickness (modify the machining conditions)

VIBRATIONS

high cutting forces.

• Reduce the cutting depth
• Low rigidity of machine-tool-workpiece assembly
• Use a tool with smaller overhang
• Excessive chip depth (both axial and radial)
• Modify the cutting speed
• Run-out – poor workpiece or tool balance
• Reduce the chip thickness
• Large tool overhang (change the cutting or machining conditions)
• Choose a suitable cutting geometry and tool material to minimize the cutting process force balance (as sharp and as positive as possible), i.e. use a tool with a lower cutting resistance
• When milling, use a tool with a smaller setting angle