Menentukan Titik Koordinat Benda Kerja .1 Handel
475 Penentuan Titik 1
46,9042 61
=
2
4
x
2 x
=
⋅ 46,9042 4
61 2
x
= 3,075685746 x
= 6,1514
39 61
=
4 y
y =
39 4 61
⋅
y = 2,557377049
z = 4 – y
x = 1,4426
Gambar 51. Perhitungan koordinat titik 1
Penentuan Titik 2
sin α =
41,6 95
α = 25,97
y = sin α · 30
y = 13,1319 y = y = 14,606
y = 71,4678 x = Cos α · 29
x = 26.71525 x = 38,5-x · 2
x = 23,5695
Gambar 52. Perhitungan koordinat titik 2
476 Penentuan Titik 3
Penentuan Titik 5
Gambar 53. Perhitungan koordinat titik 3 dan 5
c
2
= a
2
+ b
2
b
2
= c
2
– a
2
b
2
= 95
2
– 85,4
2
= 41,6068 z = b + 43
= 41,6068 + 43 = 84,6068
x = 38,5 · 2 = 77 430
Tabel 5. Koordinat hasil perhitungan benda kerja Titik
X Z
P1 6,1514
1,4426 P2
23,0605 –71,4678
P3 20
–93,9743 P4
20 –115
P5 77
–84,6068
477 2.6.2 Lengkungan
CM = 11,0 mm BM = 16,0 mm
K = CB = ? mm
cos α =
CM BM
sin α =
CB BM
=
11mm 16 mm
= 0,6875 CB
= sin α · BM = 46,567° · 16,0 mm
= 0,7261 – 16,0 mm
cos α
α α
α α
= 46,567° CB
= 11,618 mm = K
oder c
2
= a
2
+ b
2
b =
2 2
− c
a
=
2 2
16 11
−
b = 11,618 mm = K l
K 11,0
11,61 13,0
10,58 14,0
9,31 15,0
7,74 16,0
5,07 11
11,61
478 2.6.3 Paron Bola
a b
Gambar 54. Dimensi Paron Bola a dan dimensinya b
Gambar 55. Detail perhitungan kontur paron bola
479
Gambar 56. Penentuan titik koordinat paron bola
2.7 Kecepatan Potong dan Kecepatan Asutan 2.7.1 Kecepatan Potong Vc
Vc = π
π π
π π
× d × n 1000 mmenit
d = Diameter Benda Kerja n = Jumlah putaranmenit rpm
π = Phi = 3,14
Vc Dipengaruhi oleh: a Bahan
b Jenis alat potong c
Kecepatan penyayatanasutan d Kedalaman penyayatan