OPERASI-OPERASI PERMESINAN

Operasi Permesinan

1

TurningN = rotational speed, rev/min v = cutting speed, m/min D0 = original diameter, mm Df = final diameter, mm d = depth of cut f = feed, mm/rev fr = feed rate, mm/min Tm = time of actual machining, min L = length, mm MRR = material removal rate mm3/min

N

v

D

f0

r

NfL

D D0

f

2d

Tm

f

MRR vfdr

Operasi Permesinan

2

Operasi Turning Lainnya(a) facing (b) taper turning (c) contour turning (d) form turning (e) chamfering (f) cutoff (g) threading (h) boring (i) drilling (j) knurling

Operasi Permesinan

3

Mesin Lathe

Operasi Permesinan

4

Metoda Pencekaman Benda Kerja Pada Lathe

(a) mounting the work between centers using a dog (b) three-jaw chuck (c) collet (d)face plate for non cylindrical workpartsOperasi Permesinan 5

Contoh Urutan Operasi Turning

(1) feed stock to stop (2) turn main diameter (3) form second diameter and spotface (4) drill(5) chamfer (6) cutoffOperasi Permesinan 6

DrillingN = spindle speed, rev/min v = cutting speed, mm/min D = drill diameter, mm f = feed, mm/rev Fr = feed rate, mm/min Tm = machining time, min T = work thickness, mm A = approach allowance MRR = material rate of return

v N D

A 0.5D tan(90 ) 2MRR

Tm Tm

d

f

r

f

r

Nf

D

2

f

tA

r

4

f

r

Operasi Permesinan

7

Operasi Drillling Lainnya

(a) reaming (b) tapping (c) counter boring (d) countersinking (e) center drilling (f) spot facingOperasi Permesinan 8

Mesin Drilling

Drill press & Radial drill pressOperasi Permesinan 9

Milling

Horizontal milling Vertical milling

Operasi Permesinan

10

Horizontal Mill

Types of horizontal boring mill (a) boring bar is fed into a rotating workpart (b) work is fed past a rotating boring bar

Operasi Permesinan

11

Vertical Mill (2)

Vertical boring millOperasi Permesinan 12

Milling

Types of milling operation: (a) peripheral or plain milling (b) face millingOperasi Permesinan 13

Peripheral Milling

(a) slab milling (b) slotting (c) side milling (d) straddle milling

Operasi Permesinan

14

Tipe Pemotongan Milling

(a) up milling (b) down millingOperasi Permesinan 15

Face Milling(a) conventional face milling (b) partial face milling (c) end milling (d) profile milling (e) pocket milling (f) surface contouring

Operasi Permesinan

16

Parameter Pemesinan Millingv N D

f

r

N nt f

MRR wd L A

f

r

A d (D d )

T

m

f

r

Nt = number of teethOperasi Permesinan 17

Mesin Milling (1)

(a) horizontal (b) verticalOperasi Permesinan 18

Mesin Milling (2)

(a) universal-overarm (b) ram typeOperasi Permesinan 19

Machining Centers Automated machine tool capable of performing multiple machining operation under CNC control, having features: Automatic tool-changing Pallet shuttles Automatic workpart positioning

Operasi Permesinan

20

Turning Centers

Operasi Permesinan

21

Operasi pada Mill-Turn Centers

(1) turn second diameter (2) mill flat with part in programmed angular position (3) drill hole (4) cutoffOperasi Permesinan 22

Operasi Milling Lainnya

(a) shaping (b) planningOperasi Permesinan 23

Bentuk-bentuk Shaping & Planing

Operasi Permesinan

24

Mesin Shaper

Operasi Permesinan

25

Mesin Planer

Operasi Permesinan

26

Operasi Milling LainnyaBroaching

(a) external broaching (b) internal broachingOperasi Permesinan 27

Sawing

(a) power hacksaw (b) bandsaw (c) circular sawOperasi Permesinan 28

High Speed MachiningWork Material Aluminum Cast iron, soft Cast iron, ductile Steel, free machining Steel, alloy Titanium Solid Tools (end mills, drill) Conventional High Cutting Speed (m/min) Speed (m/min) 300 3000 150 360 105 250 105 360 75 250 40 60 Indexable Tools (face mills) Conventional High Cutting Speed (m/min) Speed (m/min) 600 3600 360 1200 250 900 360 600 210 360 45 90

Operasi Permesinan

29