Proses Manufaktur Machining operation and machine tools Machining

Proses Manufaktur Machining operation and machine tools

Machining operation and machine tools • Machining (prsoses permesinan) merupakan proses manufaktur paling serbaguna dan akurat dalam kemampuannya untuk memproduksi beragam bentuk part. • Casting (pengecoran) juga dapat memproduksi beragam bentuk, tetapi kurang dalam presisi dan akurasi.

Proses permesinan • Setiap proses permesinan menghasilkan karakteristik geometris dikarenakan 2 faktor: • Pergerakan relatif antara tool dan juga benda kerja • Bentuk dari cutting tool • Klasifikasi operasi dari bentuk benda yang dibuat • Generating: geometri dari benda kerja dipengaruhi oleh lintasan feed dari cutting tool (pahat) • Forming: bentuk dari benda kerja dibuat dari bentuk geometri cutting tool (pahat)

Generating

Forming

Kombinasi

Turning and lathe basics • Turning is a machining process in which a single-point tool removes material from the surface of a rotating workpiece N = rotational speed, rev/min v = cutting speed, m/min D 0 = 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 mm 3/min

Operation related to turning

Lathe (Mesin bubut)

Contoh urutan operasi turning

Mesin bor • Boring is similar to turning. It uses a single-point tool against a rotating workpart. • The difference is that boring is performed on the inside diameter of an existing hole rather than the outside diameter of an existing cylinder.

Drilling and related operation • Drilling, is a machining operation used to create a round hole in a workpart. • This contrasts with boring, which can only be used to enlarge an existing hole. N = 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

Operation related to drilling

Mesin drilling Upright Drill press & radial drill press

Milling • Milling is a machining operation in which a workpart is fed past a rotating cylindrical tool with multiple cutting edges

Peripheral milling • In peripheral milling, also called plain milling, the axis of the tool is parallel to the surface being machined, • The operation is performed by cutting edges on the outside periphery of the cutter.

Face milling • In face milling, the axis of the cutter is perpendicular to the surface being milled, • machining is performed by cutting edges on both the end and outside periphery of the cutter

Parameter permesinan milling (peripheral) • Nt = number of teeth

Parameter permesinan milling (face milling)

Mesin milling

Mesin milling

Machining centers A machining center is a highly automated machine tool capable of performing multiple machining operations under computer numerical control in one setup with minimal human attention, having features: • Multiple operations in one setup • Automatic tool-changing • Pallet shuttles • Automatic workpart positioning

Contoh operasi pada mill-turn centers

Other machining operation • Shaping and planing • Broaching • Sawing

Shaping and planning Shaping and planing are similar operations, both involving the use of a single-point cutting tool moved linearly relative to the workpart.

Mesin planer dan shaper

Bentuk-bentuk shaping dan planing

Broaching is performed using a multiple-teeth cutting tool by moving the tool linearly relative to the work in the direction of the tool axis

Sawing

High speed machining

Tugas 1. 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. 5 m/s, f=0. 3 mm/rev. 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 minggu depan