Общий каталог Sumitomo 2018 - 2019 - страница 560

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Chip Control

Type of Chip Generation Type of Chip Control

abcdFeed rateABCDE
Large feed rate
Continuous chipsChip is shearedChips appear toChips crack beforeSmall feed rate
with good surfaceand separated bybe torn from thereaching the cutting
finish.the shear angle.surface.point.5 5 NC lathe
(For automation)
Steel, Stainless steel Steel, Stainless steelSteel, Cast iron (Very low~ General lathe
(Low speed)speed, very small feedrate) Cast iron, Carbon5 5 (For safety){
EasyWork deformationDifficultGood : C type, D type
A type : Twines around the tool or workpiece, damages the machined surface
LargeRake angleSmalland affects safety.
SmallD.O.C.LargeB type : Bulky, causes problems in the automatic chip conveyor and chipping Poor
FastCutting speedSlowoccurs easily.

E type : Causes spraying of chips, poor machined surface due to chattering, chipping, large cutting force and high temperatures. Factor of Improvement Chip Control j Increase feed rate

4,0

t1 t2>t1

ff >f2,0
121

When feedrate increase, chips become 0,1 0,2 0,3 0,4 0,5

thick and chip control improves. Feed rate (mm/rev)

k Decrease side cutting edge

< 45°

1 2 1

t1 t2>t1 f f 15°

Even if feed rate is the same, smaller

side cutting edge angle makes chips

thick and chip control improves.0,20,250,30,35
Feed rate (mm/rev)
l Decrease nose radius
r1,6
t1r

r 2 < 1

t2 1 t2>t1 f f

0,8

Even if depth of cut is the same, smaller nose radius

makes chip thick and chip control improves.

* Cutting resistance increases in proportion with

the width of the contact surface. Therefore, with 0,4

a larger nose radius, cutting resistance and

back force increases, chattering may also occur.

However, with the same feedrate, a smaller nose 0,2 0,25 0,3 0,35

radius would produce a poorer surface finish. Depth of cut (mm)