Week 10 Per Me Sinan

Operasi Pemesinan & Mesin Perkakas

TI2121 - Proses Manufaktur - 10 2

Klasifikasi Komponen Pemesinan

(a) rotational (b) non-rotational (prismatic)


Bentuk Permukaan Potong

(a) straight turning (b) taper turning (c) contour turning (d) plain milling (e) profile milling


Forming: Bentuk Pemotongan

(a) form turning (b) drilling (c) broaching


Kombinasi Forming dan Pergerakan Pahat

(a) thread cutting on a lathe (b) slot milling


Turning

N = rotational speed, rev/min

v = cutting speed, m/minD0 = original diameter, mm

Df = final diameter, mm

d = depth of cutf = feed, mm/revfr = feed rate, mm/min

Tm = time of actual machining, min

L = length, mmMRR = material removal

rate mm3/minDv

N0

dDD f2

0

Nffr

fTr

m

L vfdMRR


Operasi Turning Lainnya

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


Mesin Lathe


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

workparts


Contoh Urutan Operasi Turning

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


Boring Mill (1)

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


Boring Mill (2)

Vertical boring mill


Boring Mill (3)

Boring bar made of cemented carbide


Drilling

N = spindle speed, rev/min

v = cutting speed, mm/min

D = drill diameter, mmf = feed, mm/revFr = feed rate, mm/minTm = machining time,

minT = work thickness, mmA = approach allowanceMRR = material rate of

return

D

vN

Nffr fT

r

m

At

)2

90tan(5.0

DA fTr

m

d

4

2 fD rMRR


Operasi Drillling Lainnya

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


Mesin Drilling

Drill press & Radial drill press


Milling

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


Peripheral Milling

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


Tipe Pemotongan Milling

(a) up milling (b) down milling


Face Milling

(a) conventional face milling

(b) partial face milling

(c) end milling (d) profile milling (e) pocket milling (f) surface

contouring


Parameter Pemesinan Milling

• Nt = number of teeth

fT

fnf

r

m

r

tr

AL

dDdA

wdMRR

fN

D

vN

)(


Mesin Milling (1)

(a) horizontal (b) vertical


Mesin Milling (2)

(a) universal-overarm (b) ram type


Machining Centers

• Automated machine tool capable of performing multiple machining operation under CNC control, having features: Automatic tool-

changing Pallet shuttles Automatic

workpart positioning


Turning Centers


Operasi pada Mill-Turn Centers

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


Operasi Milling Lainnya

(a) shaping (b) planning


Bentuk-bentuk Shaping & Planing


Mesin Shaper


Mesin Planer


Operasi Milling Lainnya

• Broaching

(a) external broaching (b) internal broaching


Sawing

(a) power hacksaw (b) bandsaw (c) circular saw


High Speed Machining

Solid Tools (end mills, drill) Indexable Tools (face mills) Work Material Conventional

Speed (m/min) High Cutting

Speed (m/min) Conventional

Speed (m/min) High Cutting

Speed (m/min) Aluminum 300 3000 600 3600 Cast iron, soft 150 360 360 1200 Cast iron, ductile 105 250 250 900 Steel, free machining 105 360 360 600 Steel, alloy 75 250 210 360 Titanium 40 60 45 90


Tugas1. Pilih sebuah komponen nyata yang memiliki proses

turning. Sketsa kondisi material awal dan setiap tahap proses

pemotongan hingga bentuk akhir produk. Tentukan parameter pemesinannya; jika v=2.5m/s,

f=0.3mm/rev. Dikumpulkan di LSP Kamis, 6 November 2003 jam 12.00

2. Pilih sebuah komponen nyata lainnya yang memiliki proses milling Sketsa kondisi material awal dan setiap tahap proses

pemotongan hingga bentuk akhir produk.• Tentukan diameter pahat yang cocok untuk setiap proses

pemesinan komponen tersebut• Tentukan parameter pemesinannya• Dikumpulkan di LSP Kamis, 13 November 2003 jam 12.00

Documents

Week 10 Per Me Sinan