Техническая информация Sumitomo - страница 5

Chip Control

• Type of Chip Generation
• Type of Chip Control

Spiralling Shearing Tearing Cracking

Work material Work material Work material Work material

chips with good and separated by be torn from the before reaching

• Factor of Improvement Chip Control

(1) Increase Feed Rate (f)

When feed rate increases, chips become thick and chip control improves. (2) Decrease Side Cutting Edge (θ ) θ: θ:

22 11

t t 1 2

f f :‥‥: ＜: t ＞t

2 1 then 2 1

Even if feed rate is the same, smaller side cutting edge angle makes chips thick and chip control improves.

(3) Decrease Nose Radius (R E )

t 22 t 11 RE1 RE2 Large Small nose radius nose radius f f RE‥‥RE2＜RE1 then t ＞t 2 1

Even if feed rate is the same, a smaller

nose radius makes chip thick and chip

control improves.

* Cutting force increases in proportion with

the length of the contact surface. Therefore,

a larger nose radius increases back force

which induces chattering. With the same

feed rate, a smaller nose radius produces a

rougher surface finish.

｛Good: C type, D type

A type: Twines around the tool or workpiece, damages the machined surface and affects safety. Poor B type: Causes problems in the automatic chip conveyor and chipping occurs easily. E type: Causes spraying of chips, poor machined surface due to chattering, chipping, large cutting force and high temperatures.

4 . 0

2.0

0.1 0.2 0.3 0.4 0.5

Feed Rate (mm/rev)

4 5 °

15°

0.2 0.25 0.3 0.35

Feed Rate (mm/rev)

1. 6

N

0.8

0.4

0.5 1.0 1.5 2.0

Depth of Cut (mm)