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Trochoidal millingProcess description

� 2D roughing/high material removal method using HSM techniques in a confined space or slot in difficult materials (ISO H, S)

� Tool is programmed with a roll entry and exit from cut – controlling the arc of engagement– low cutting forces allowing high depths of cut

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Trochoidal millingProcess methods – narrow groove/profile

� Groove less than 2 x Dc

– a continuous spiraling path feeding in the radial direction to form a groove or a profile

– the feed is constant with continuously varying radial cut– 50% of time out of cut

� Dcmax = 0.7 x slot width Dm

� ap = max 2 x Dc

� aemax = 20% Dc

� w ≈ 8% Dc to give ae max 20%� calculate programmed feed - vfDvf

ae max

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Trochoidal millingProcess methods – wide groove

� Groove wider than 2 x Dc

– roll into cut – programmed radius = 0.5 x Dc

– G1 at ae = 0.1 x Dc

– roll out of cut – programmed radius = 0.5 x Dc

– rapid to next start position

� Radial depth (ae) = 15%� Axial depth (ap) = max 2 x Dc

� Programmed rad (radm) = 0.5 x Dc

� Radius feed – Radvf = 0.5 x G1

groo

ve w

idth

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Trochoidal milling

Cutting information� R216.24-08050-EAK 19P 1620� Dia 8 mm� Flutes 4� Radius 2 mm� Time/slot 1.6 min� Tool life 10 slots

Shaft component Inconel 718� No of slots 24� Width 12 mm� Length 30 mm� Flange depth 20 mm

Dia vc n w aemax aemax/D kr - θ hex fz zn fn v fm Dvf v f va ap Timemm m/min rpm mm mm % deg mm mm mm/rev mm/min mm mm/min mm/min mm min

8 75 2984 0,67 1,59 20% 53 0,07 0,09 4 0,35 1047 4 349 18,60 16 1,61

Dvf

ae max

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Programming methodsBest Results

Trochoidal Slotting Plunging

CutterR216.24-08050EAK19P

1620R216.13-12030-BS12P

1630R216.13-12030-BS12P

1630

zn 4 3 3

vc 75 40 30

n 2984 1060 796

fz 0.09 0.04 0.04

ae 0,67(step over) 12 0,3

ap 16 8 16

vf 349 127 96

Time /slot 1’35” 35” 2’23”

No slots 7 slots 3 slots 4 slots

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1. CoroMill 390 – Ø16

Test casing – Inconel 718Scallop milling

Cutter body Insert D 3 zn v c n f z v f ap ae Q Timemm m/min rpm mm mm/min mm mm cm3/min min/sec

1 R390-016A16-11H R390-11T308M-PL 1030 16 2 30 597 0,10 119 5 2 1,2 2'45"

2 1620 12 4 75 1989 0,08 637 5 1 3,2 1'15"R216.24-12050GAK26P

Note:- time per scallop

2. CoroMill Plura - Ø12

15

10 rad

Ø845 15

10 rad

Ø845

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Test casing – Stainless steelScallop milling

Cutter body Insert D 3 zn vc n fz v f ap ae Q Timemm m/min rpm mm mm/min mm mm cm3/min min/sec

1 R390-016A16-11H R390-11T308M-PL 1030 16 2 200 3978 0,15 1194 5 2 11,9 0'25"

2 1630 12 4 170 4509 0,06 1082 5 1 5,4 1'00"R216.24-12050AK26P

1. CoroMill 390 – Ø16 2. CoroMill Plura - Ø12

Note:- time per scallop