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B GIO DC V O TO

I HC NNG

V NGC C

NGHIN CU THIT K V CH TO KHUN P

V THUC BNG CNG NGH CAD/CAM/CNC

Chuyn ngnh : Cng ngh Ch to my

M s : 60.52.04

TM TT LUN VN THC S K THUT

Nng - Nm 2013

Cng trnh c hon thnh ti

I HC NNG

Ngi hng dn khoa hc: PGS.TS TRN XUN TY

Phn bin 1: TS. LU C BNH Phn bin 2: PGS.TS. L VIT NGU

Lun vn c bo v trc Hi ng chm Lun vn tt nghip thc s K thut hp ti i hc Nng vo ngy 18 thng 04 nm 2013.

C th tm hiu lun vn ti:

- Trung tm Thng tin - Hc liu, i Hc Nng - Trung tm Hc liu, i Hc Nng

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M U 1. TNH CP THIT CA TI

Ngy nay, vi s pht trin nhanh chng ca khoa hc v cng ngh trn tt c cc lnh vc th cc sn phm c kh ngy cng phi c yu cu cao hn v cht lng sn phm, mc t ng ho sn xut v c bit l chnh xc hnh dng hnh hc ca sn phm. V vy, cc cng ngh gia cng truyn thng trn cc my vn nng kh p ng tt c nhu cu ny, do s cnh tranh ca sn phm trn th trng b hn ch. Thc t i hi phi pht trin v nghin cu cc cng ngh mi nhm nng cao chnh xc, hnh dng hnh hc ni ring v nng cao cht lng sn phm ch to ni chung.

Vic ch to khun mu ng vai tr rt quan trng trong cng ngh ch to my. Khun mu c hnh dng bt k, nht l cc mu c hnh dng bn trong phc tp i hi rt nhiu thi gian thit k v gia cng. Vi cng ngh CAD/CAM/CNC vic to khun mu v gia cng nhng chi tit c kh c hnh dng hnh hc phc tp v chnh xc cao tr thnh hin thc.

nc ta hin nay nhu cu khun mu cho cc dy chuyn sn

xut thuc vin l rt ln. hn ch nhp ngoi v lm ch trong vic sn xut thuc th vic nghin cu cng ngh ch to khun p v l ht sc cn thit v c ngha thc t cao.

Vi mong mun tm hiu v lnh vc thit k v gia cng khun mu trn my CNC ngi nghin cu chn ti: Nghin cu thit k v ch to khun p v thuc bng cng ngh CAD/CAM/CNC 2. MC CH NGHIN CU

Nghin cu thit k v cng ngh gia cng khun p v thuc trn my CNC, nhm ng dng vo thc t sn xut ti cc cng ty dc phm khu vc min trung.

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3. I TNG V PHM VI NGHIN CU

3.1. i tng nghin cu - My phay CNC Concept Mill 155 - Phn mm CAD/CAM/PROENGINEER. - Chi tit khun p v thuc. 3.2. Phm vi nghin cu - Xy dng bin dng khun p v thuc. - Nghin cu tnh ton thit k bin dng v ch to khun p v

thuc. - Nghin cu cng ngh gia cng bin dng khun p v thuc

trn my phay CNC. V c s l lun, trong lun vn ny ch ch phn tch nhng

phn lin quan n ti, ch yu hng n tnh thc dng thit k v ch to thnh cng bin dng khun p v thuc, do vic kim tra bn, chn vt liu lm khun trong qu trnh lm vic cha c quan tm. 4. PHNG PHP NGHIN CU

ti c nghin cu da trn phng php kho st t thc t cc loi khun trong ngnh dc phm, t tng hp l thuyt thit k v ch to thc nghim mt b khun p v thuc hon chnh. 5. D KIN KT QU T C

- Nghin cu dy sn xut thuc ty trn my Model DDP - 250 v nguyn l lm vic ca khun p v thuc.

- Thit k v ch ch to mt b khun p v thuc hon chnh bng cng ngh CAD/CAM/CNC trn my Concept Mill 155, ti vin cng ngh c kh v t ng ha - Trng i Hc Bch Khoa - i Hc Nng.

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- Nghin cu thit k v ch to cc loi khun c bin dng phc tp ph hp vi nhu cu s dng ca ngnh sn xut dc phm. 6. CU TRC LUN VN

Ngoi phn m u, kt lun, ti liu tham kho v ph lc trong lun vn gm c cc chng nh sau:

Chng 1: TNG QUAN V KHUN P V THUC. Trong , trnh by cu to, nguyn l lm vic ca khun p v

thuc v gii thiu cc kiu khun ph bin, cc phng php lm ngui.

Chng 2: TNH TON THIT K KHUN. Trong , gii thiu v cng ngh dp v thuc ca my Model

DPP - 250, tm hiu vt liu PVC, b phn gia nhit, tnh ton nhit gia nhit, p sut, xc nh khun nh hnh v thuc.

Chng 3: C S L THUYT GIA CNG TRN MY CNC

Gii thiu tng quan v cng ngh CAD/CAM/CNC, nghin cu phn mm Pro/Engineer Wildfire 4.0

Chng 4: THIT K CH TO KHUN P V THUC

BNG CNG NGH CAD/CAM/CNC ng dng phn mm Pro/Engineer Wildfire 4.0 vo cc cng vic

nh: thit k v dng hnh chnh xc bin dng ca khun; T m hnh ny, ng dng phn mm Pro/Engineer Wildfire 4.0 phn tch v lp trnh m phng qu trnh gia cng v xut chng trnh gia cng di dng tp tin cha m lnh G - Code. T cc chng trnh ta chuyn sang gia cng trn my cng c Concept Mill 155 ti vin c kh v t ng ha, trng i hc Bch khoa Nng.

Tin hnh gia cng cc chi tit khc v lp rp hon thin b khun p v thuc.

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CHNG 1: TNG QUAN V KHUN P V THUC 1.1. CU TO V NGUYN L LM VIC CA KHUN P V THUC

Hnh 1.1. Cu to khun p v thuc

L kh nn vo lm ngui sn phm

L ra ca kh nn

a. khun trn

L thot kh

L thot kh

b. Khun di

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1.2. PHN LOI KHUN 1.2.1. Khun hai tm

Hnh 1.2. Khun hai tm c knh dn ngui

Hnh 1.3. Kt cu khun hai tm

1.2.2. Khun ba tm 1.2.3. Khun p 1.2.4. Khun p nha


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1.3. CC PHNG PHP LM NGUI 1.3.1. Lm ngui bng kh 1.3.2. Lm ngui bng nc hoc hn hp ethylene glycol v

nc 1.3.3. Khun c lm ngui bng kh

1.4. H THNG DN HNG 1.4.1. Cht dn hng 1.4.2. Bc dn hng

1.5. KT LUN Qua chng ny chng ta bit c kh nng ca cng ngh p

v cung cp mt cch tng th kin thc v cc c tnh ca qui trnh p, n gip chng ta hiu c lm th no to ra mt sn phm c cht lng cng nh tng nng sut trong qu trnh sn xut.

Tm hiu c cc loi khun p, bit c cc phng php lm ngui v mt s b phn dn hng ca khun.

CHNG 2: TNH TON THIT K KHUN

2.1. TNG QUAN V MY DP V THUC T NG MODEL DPP -250

2.1.1. Nhim v ca my dp v thuc My dp v thuc s gii quyt cc vn sau: a) Chng trnh khng ch nhit Lp trnh cho b gia nhit khi t nhit yu cu th my mi

bt u hot ng v nhit lun gi mc n nh trong sut qu trnh my lm vic.

b) Chng trnh iu khin ng c in chnh (ko c cu cu lt)

ng c in s cung cp khi nhit b gia nhit t yu cu.

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ng c in chy mang c cu cu - lt i mt chu trnh (mt hnh trnh kp) th dng li 2,5 giy, ch b nh hnh thi gian theo nhp iu khin.

Khi 2 xy- lanh 2.0 v 3.0 ca b nh hnh v li v tr ban u th ng c in c cung cp in li thc hin chu k k tip.

c) Chng trnh iu khin u kp trt PVC Khi xy lanh 1.0 gia nhit i v hoc 2 xy lanh 2.0 v 3.0 ca

b nh hnh lui v v tr ban u, lc ny u kp trt chm cng tc hnh trnh 6LS, u kp kp dy PVC. Khi u kp i ht mt hnh trnh tin s chm vo cng tc hnh trnh 5LS, u kp nh ra v i tip hnh trnh li li.

d) Chng trnh iu khin hai ng c cp phi v cun sn phm

Khi u kp trt ko dy PVC lm cho trc l trng lng ca b cp phi c nng ln, lc ln n im cht trn trc l s chm vo cm bin 2LS, tc ng cho ng c cp phi c cung cp in quay x phi PVC v nh trng lng ca bn thn trc l c xu hng ri xung trong rnh trt, ko dy PVC lun c gi cng. Khi trc l trng lng ri xung n im cht di s chm

vo cm bin 1LS, lc ny ng c cp phi mt in dng quay khng x phi na.

Tng t nh ng c cp phi, ng c cun sn phm cng

hot ng da theo nguyn tc trng lng (ca trc l), vi 2 cm bin 3LS v 4LS. ng c cun sn phm c chu k hot ng ngc li vi chu k ca ng c cp phi, ngha l khi trc l trng lng i xung n im cht di th ng c cun sn phm c in cung cp quay cun sn phm. Khi trc l trng lng ln

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n im cht trn th ng c cun sn phm b ngt in, dng quay.

e) Cc ch th, ch bo + Hin th nhit gia nhit. + n bo ngun AC v ngun DC. + ng h bo p sut kh nn.

Hnh 2.1. S nguyn l my p v thuc Model DDP - 250 K hiu: 1.0: xy lanh c lp vi b phn gia nhit 2.0 v 3.0: xy lanh c lp vi b khun (khun trn v khun

di) 1LS, 2LS, 3LS, 4LS, 5LS, 6LS: cc cm bin 2.1.2. Gii thiu v cng ngh dp v thuc Thit b dp v thuc c iu khin t ng, phi liu bng vt

liu PVC (Polyvinilclorit). Khi dp v c gia nhit cho phi liu v dng khun thi hi to nh hnh cho v thuc.

sn xut ra thnh phm v thuc, cc thit b sn xut hin i thc hin lin hon v t ng: nn vin thuc - dp v thuc - vo thuc cho v - dn p giy nhm mt trn v - in cc thng tin ln giy nhm - dp ct hnh dng v - m sn lng v mt cch linh hot, chnh xc vi sn lng v kch thc theo yu cu.

L cp phi L cun sn phm

Gia nhit

nh hnh

2LS

1LS 3LS

4LS

1.0 2.0 6LS 5LS

3.0

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2.1.3. Tnh hnh ng dng v pht trin Vit Nam 2.2. GII THIU VT LIU NHA

2.2.1. Khi nim 2.2.2. Phn loi nha 2.2.3. Mt s c tnh ca nha nhit do Vt liu dng sn xut v thuc l loi polymer tng hp PVC

(polyvinilclorit). y l mt hp cht gm cc phn t c hnh thnh do s lp

li nhiu ln ca mt loi, hay nhiu loi nguyn t, hoc mt nhm nguyn t (n v cu to l Monomer).

PVC ny thuc loi Polymer nhit do, di tc dng ca lc mt nhit nht nh, cc phn t trt ln nhau tr thnh do chy (d to hnh) v khi di nhit ny s rn tr li, do cc monomer trng lp l nhng cht n gin, khi lng phn t thp, c cha ni i.

nCH2 = CH -> [ [ - CH2 - CH - ] n | |

Cl Cl Vinylcorit Polyvinylcorit

Polyvinylcorit c tnh cht sau: Bng 2.5. bn ca vt liu Polyvinylcorit

Kh/lng ring (g/cm3 )

M un ko (MPa.102)

Gii hn ko (MPa)

gin khi t (%)

1,3- 1,58 24- 42 41- 52 40 - 80

PVC dng lm v thuc thuc nhm Polymer nhit do, nhm ny b ph hy khi chuyn t do sang gin. Yu t gy nn ph hu l nhit thp m tc bin dng ln, hoc do cc vt nt c sn.

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V tnh cht nhit, h s gin n ph thuc vo loi lin kt gia cc nhm nguyn t hoc phn t, h s cng ln khi cng lin kt cng yu.

PVC c h s gin n: 50 180: 106 C-1

dn nhit thp: 0,12 0,30 W/m.o c Do nhng tnh cht trn, PVC (Polymer nhit do) c gia cng

nhit cao hn nhit thy tinh ho v p lc duy tr, khi lm lnh sn phm vn bo ton hnh dng.

Mt khc, PVC sn xut v thuc, cn phi i qua h thng kh mi v v trng nghim ngt. 2.3. TRM GIA NHIT

2.3.1. Cc phng php gia nhit 2.3.2. Gii thiu trm gia nhit B gia nhit dng to nhit ng theo yu cu, nhm cung

cp cho phi liu PVC mm, chy do trc khi a n b p thi nh hnh.

Cun PVC c gia nhit nng ln theo nhit yu cu (khong 1400c 1600c ) nh 2 a tip xc nhit. a tip xc nhit gm 2 m phng mang ngun nhit t b to nhit. Khi gia nhit, 2 m phng ny kp cht vt liu PVC bng hnh trnh i ra ca xy-lanh kh nn 1.0 (khong 5 giy), v nh kp ra theo tng bc iu khin. Khi m hnh khng lm vic, 2 m phng t nh ra. 2.4. TNH TON NHIT GIA NHIT V P SUT

Nh nu trn mc 2.2.3, vt liu PVC c dn nhit thp, v nhit cung cp phi cao hn nhit thu tinh ho (chuyn t trng thi rn sang cu trc ging cao su, mm do).

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Nhit thy tinh ho c xc nh da vo ng bin thin khi lng ring theo nhit . PVC c nhit thy tinh ho 1050c 1100c.

Th - nhit thy tinh ha, Tnc - nhit nng chy A - Polymer nh hnh hon ton, B - Polymer bn tinh th, C -

Polymer tinh th Do tc gia nhit cn ph thuc vo thi gian, vo dy

ca tm PVC. Vi m hnh my dp v thuc ny, dng cun PVC c dy

0,3mm ta chn c nhit gia nhit nh sau: Bng 2.6. Thng s gia nhit v p sut

dy PVC Nhit cung cp p sut Thi gian 0,30mm 1400c 1560c 68 bars 5 7 giy

2.5. TRM NH HNH V THUC 2.5.1. Gii thiu trm nh hnh v thuc M hnh dng xy - lanh kh nn 2.0 mang khun thi kh nn

trn, v xy - lanh kh nn 3.0 mang khun nh hnh di.

Khi Lng ring

Th Tnc t0c

A

B

C

Hnh 2.5 S thay i ca khi lng ring theo nhit

12

Khi dy PVC gia nhit mm, c u kp trt ko vo ng v tr theo bc iu khin (v tr b khun nh hnh), c hai xy lanh 2.0 v 3.0 mang khun thi cng khun nh hnh cho dy PVC l khun pha di, ng thi lm ngui nhanh bo ton hnh dng cho v thuc.

Sau mt khong thi gian iu khin (5 giy), c hai xy lanh 2.0 v 3.0 u i vo, ch thc hin cho chu k k tip.

Khi c hai xy lanh kh nn 2.0 v 3.0 li v v tr ban u, u kp trt s ko dy PVC ra khi v tr nh hnh, tip tc a n ng c cun sn phm pha sau.

2.5.2. Xc nh khun nh v v thuc Phi liu PVC c gia nhit mm do ra, nn khun thi i

xung lm cho phi liu PVC dn ra in y th tch ca khun, ng thi thi kh nn ra lm ngui bo ton hnh dng ca v (thi gian ho rn li khong 3 5 giy).

Lc p nh hnh khng da vo lc c hc, nn b khun nh hnh c chn vt liu bng hp kim nhm:

Khun l nh hnh pha di c thit k rnh thot kh sn phm m bo hnh dng.

Khun p nh hnh pha trn c thit k l thi kh, lm lm ngui sn phm

55

8

8 Rnh lm ngui sn phm Rnh thot hi

Hnh 2.6 Mt ct ngang ca b khun nh hnh

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2.6. KT LUN Trong chng ny chng ta bit c nguyn l hot ng ca

my dp v thuc Model DPP- 250 v cng ngh dp v thuc. Phn loi c cc tnh nng ca cc loi vt liu PVC, nhm ng

dng lm vt liu v thuc. Bit c cc phng php gia nhit trong nhiu kiu khun khc

nhau. CHNG 3: C S L THUYT GIA CNG TRN

MY CNC 3.1. TNG QUAN V CNG NGH CAD/CAM/CNC

3.1.1. Khi qut v iu khin s 3.1.2. Lch s pht trin ca NC

3.2. CC H THNG IU KHIN CHNG TRNH S 3.2.1. H thng iu khin NC (Numerical Control) 3.2.2. H thng iu khin CNC (Commputer Numerical

Control) 3.2.3. H thng iu khin DNC (Direct Numerial Control) 3.2.4. H thng sn xut linh hot FMS (ManuJacturing

System) 3.2.5. H thng sn xut tch hp CIM (Computer Intergated

Manufacturing) 3.3. THIT K CHNG TRNH GIA CNG NC

3.3.1. Cu trc chng trnh NC 3.3.2. Cu trc mt cu lnh

3.4. CC CHC NNG CA MY 3.4.1. Chc nng dch chuyn 3.4.2. Chc nng vn hnh my

3.5. CC PHNG PHP LP TRNH


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3.5.1. Lp trnh bng tay 3.5.2. Lp trnh bng my 3.5.3. Phng php chung khi lp trnh gia cng

3.6. CNG NGH CAD/CAM TRONG GIA CNG 3.6.1. Gii thiu v CAD/CAM 3.6.2. Mt s phn mm CAD/CAM s dng trong nghnh c

kh ch to 3.7. GII THIU PHN MM PRO/ENGINEER TRONG THIT K V GIA CNG 3.8. GII THIU MANUFACTURING TRONG PRO/ENGINEER

3.8.1. Cch thit lp c bn trong m un Manufacturing 3.8.2. Mt s chu trnh phay trong m un Manufacturing 3.8.3. Cc thng s c bn khai bo trong qu trnh gia cng 3.8.4. Chn phi v phng php ch to phi 3.8.5. Lu qu trnh thit lp quy trnh cng ngh gia cng

chi tit trn PRO/ENGIENEER 3.9. KT LUN

Ngy nay, cng vi s pht trin ca Khoa hc - Cng ngh, vic ng dng tin hc v iu khin s cho php cc nh ch to my nghin cu a vo my cng c cc h thng iu khin cho php thc hin cc qu trnh gia cng mt cch linh hot hn, thch ng vi nn sn xut hin i v mang li hiu qu kinh t cao v mt khoa hc.

CAD/CAM l lnh vc nghin cu nhm to ra cc h thng t ng thit k v ch to sn phm trong :

CAD - thit k sn phm c s tr gip ca my tnh

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CAM - ch to sn xut c s tr gip ca my tnh, m phng qu trnh ch to, lp trnh ch to sn phm trn cc my cng c t ng CNC.

ng dng phn mm Pro/engineer Wilrfire 4.0 thit k mu v t ng thit k khun l iu cn thit khi ch to khun mu, c bit khi p dng cho cc my cng c CNC

Trong chng ny phm vi nghin cu cng ngh CAD/CAM/CNC ti vin C kh v T ng ha trng i hc bch khoa Nng ng dng trong vic gia cng sn phm.

CHNG 4: THIT K V CH TO KHUN P V THUC BNG CNG NGH CAD/CAM/CNC

4.1. LP TRNH GIA CNG 4.1.1 Gii thiu my phay Concept Mill 155

Hnh 4.1. Kt cu chung ca my

1. Sng trt bn my theo X/Z 2. Vng lm vic 3. n lm vic 4. H thng ca bo v 5. tch dao 6. Nt tt khn cp 7. Khay h thng 8. H thng lp 9. B cha cht lm mt 10. Bm cht lm mt 11. Cng tc ngun 12. T in 13. Phm iu khn 14. Ngn ko bn phm my tnh 15. B my

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4.1.2. Gii thiu my tin Concept Turn 250

4.2. CHN CH CT KHI GIA CNG Chn ch ct hp l m bo nng sut cao v gi thnh gia

cng h thp khi t c nhng iu kin gia cng gia cng nh trc. Ngoi ra cn phi tn dng c tnh nng ca vt liu lm dao.

Xc nh ct bao gm: - Chn cc thng s kt cu ca dao ph hp vi iu kin gia

cng. - Xc nh cc yu t ct: chiu su ct, lng chy dao v tc

ct. - Tnh cng sut my, khi cn thit phi kim nghim li mt s

c cu v bn, cng vng v.v... Trong ngnh ch to my c rt nhiu loi vt liu khc nhau

c s dng, trong cng mt loi vt liu c thnh phn, cu trc, cng... khng ging nhau. V vy, ch ct c tnh cho mt s vt liu chun ng vi mt iu kin nht nh, cn cc vt liu khc c tnh nh cc h s gia cng thc nghim.

Chn ch ct khi phay trn my CNC cng c tin hnh theo cc bc nh chn ch ct khi phay trn cc my vn nng nh chiu su ct t, lng chy dao Sz, Spht v vn tc ct v. Tuy nhin, i vi my phay CNC cn ch khi chn lng chy dao

rng (Sz). Lng chy dao Sz c chn vi gi tr Szmin t bn gi tr Sz:

Sz=min(Sz1,Sz2,Sz3,Sz4) (4.1) Trong :

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Sz1- l lng chy dao c xc nh theo nhm b mt, ph thuc vo lng d vi chiu su ct t v b rng phay B.

Sz2- l lng chy dao ph thuc vo bin dng cho php ca dao [?] (ng knh dao D v chiu di phn ct l).

Sz3- lng chy dao ph thuc vo bn ca dao. Sz4- lng chy dao cho php ca cng sut ng c my. Cc lng chy dao ni trn c xc nh theo cng thc sau

y: Sz1=C1Dt-0.5B-0.2 (4.2)

? ?? ?? ?

1.354 1.161

2 2 24 2

D DS Cz tBZ l B l B

? ?? ? ?? ?? ? ?? ? ? ?? ?? ?? ?

(4.3)

? ?1.353 1.16

13 2 2 2 24

D DS Cz tBZ K l D

? ? ? ?? ?? ? ?? ? ? ?? ??? ? (4.4)

1.350.19 1.16

4 4 . . 0

NS C D tz B Z n

?? ? ? ?? ?? ? ?? ? (4.5)

Trong : C1,C2,C3,C4 - h s ph thuc vo vt liu gia cng v c xc

nh theo bng 3.1. D1- ng knh quy i ca tit din dao phay (mm) (D1?1.2D) [?]- ng sut cho php ti im nguy him ca li dao phay do

bin dng un v xon gy ra (Pa - pascal) K- h s bng 0,6 khi gia cng hp kim mu v bng 0,8 khi gia

cng thp ?- cng sut ca my (%)


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Z- s rng dao tip xc vi b mt gia cng n0- s vng quay ca dao (vg/pht)

Bng 4.3. H s C1, C2, C3, C4

Vt liu gia

cng C1 C2 C3 C4

Kim loi mu 0,024 4,65.104 0,90.10-12 1,2.106

Thp 0,008 0,70.104 0,14.10-12 0,2.106

S lng chy dao vng : S = Sz.Z (mm/vg) (4.6)

n- s vng quay dao phay : 1000.Vn

D? (v/ph) (4.7)

Vn tc ct :. . . .. . . .

qvV um vx yv vn z

z

C D K K kV

T t S Z B? (m/ph) (4.8)

Trong : Cv l hng s, D l ng knh dao phay(mm), Ku l h s k n nh hng ca vt liu dao, K l h s tnh cht vt liu gia cng, k? l h s k n nh hng ca gc nghing chnh, T l tui bn ca dao, t chiu su ct, Sz lng chy dao rng, Z s rng dao phay, B chiu rng phay.

Cc thng s , h s ch s m xt n iu kin ct, vt liu gia cng, mc nh hng ca thng s n vn tc ct, lc ct, m mem xon v cng sut c xc nh theo mi phng phay.

Xc nh ch ct khi gia cng phay c xc nh theo bng

4.4 n bng 4.8 phn ph lc.

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4.3. QUI TRNH GIA CNG KHUN P V THUC Bn v chi tit khun trn

Bn v chi tit khun di

Hnh 4.7. Bn v chi tit khun trn

Hnh 4.8. Bn v chi tit khun di

Yu cu k thut:

- Gia cng khun di ng kch thc.

- Gia cng bin dng khun di t bng

Ra=1,6m

Yu cu k thut:

- Gia cng khun di ng kch thc.

- Gia cng bin dng khun di t bng

Ra=1,6m

550.05120

.05

520.05

170

0.05

R2,5

19,2

50.

0117

,50

.01

R0,5

40.

01

R3,5

2,05

0.0

3

80.01 130.01 60.01

7,5

0.01

10,5

0.0

5

100

.05

30.01

100

.05

19,8

0.0

116

,40

.01

12,1

0.0

1

80.01 130.01 30.01

2,1

0.01

R3

R4

R0,5

200

.05

10,1

50.

03

490.05

550.05

170

0.05

20

4.3.1. Gia cng khun trn a) Chng trnh gia cng bin dng v khoan l lm ngui

Hnh 4.9. Bin dng l khun trn b) Chng trnh khoan l lm ngui mt bn

Hnh 4.10. Khoan l lm ngui mt bn khun trn

L lm ngui

L lm ngui mt bn

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4.3.2. Gia cng khun di a) Chng trnh gia cng bin dng v khoan l thot kh

Hnh 4.11. Bin dng l khun di b) Chng trnh khoan l thot kh khun di

Hnh 4.12. Khoan l thot kh khun di 4.4. GIA CNG BIN DNG KHUN P V THUC 4.5. KT LUN

Phn mm Pro/engineer cho php thit k, xy dng bin dng khun p v thuc mt cch nhanh chng v c chnh xc cao,

L thot kh

L thot kh

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ng thi cho php nhp kch thc theo mi quan h tham s nn vic hiu chnh kch thc trong khi thit k d dng.

Trong mi nguyn cng cn thit cho php chn la my CNC v cc tham s ph hp vi tng b mt gia cng nh: gc ta , mt phng li dao, tc quay trc chnh, tc chy dao. gia cng khun p v thuc vi hiu qu kinh t cao cho php thit lp cc ng chy dao, hiu chnh ng chy dao v xut chng trnh sang m s G - Code iu khin my CNC.

Sn phm sau khi gia cng hon chnh cht lng n nh v t c chnh xc cao, m bo bng.

Trong qu trnh gia cng ti c mt s nhn xt nhm m bo chnh xc v bng theo yu cu ca sn phm:

- Chun b phi trc khi gia cng: phi c chun b trc bng nguyn cng phay th. B mt nh v v kp cht phi m bo cng vng trong sut qu trnh gia cng phay.

- Chun b dng c ct: kch thc dao phi ph hp vi b mt gia cng. Dao c lp vo ng v tr nh trong chng trnh. Khi so dao m bo chnh xc bng cch ct th, cho dao tip xc vi b mt chi tit sau nhp gi tr b dao vo bng Tool offset .

- Chn ng chy dao khi gia cng: vic chn ng chy dao khi gia cng th, tinh phi hn ch ti a s ln chy dao khng ti, v gim c thi gian gia cng.

- Chn dng c ct khi gia cng: vic chn dng c ct c ngha v cng quan trng, iu ny c nh hng rt ln ti nng sut, cht lng v gi thnh sn phm. Vic chn dao phi m bo pht huy ti a cng sut ct ca my, ng thi phi m bo cc yu cu k thut ca chi tit.

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- Chn ch ct: khi gia cng th chn ch ct ln (nhm tng nng sut gia cng), khi gia cng tinh chn ch ct nh

(nhm m bo bng v chnh xc gia cng). - Chn ch ti dung dch trn ngui: khi gia cng vt liu

thng xy ra hin tng lo dao nn cn phi ti dung dch lm ngui vo vng gia cng.

- thit k v ch to hon thnh mt b khun p v thuc

Hnh 4.19. B khun p v thuc

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KT LUN V HNG NGHIN CU TIP THEO

1. KT LUN 1) Trn c s nghin cu cng ngh p v thuc t ng trong cc

dy chuyn sn xut thuc ty hin nay, tc gi nghin cu thit k bin dng ca khun p v thuc v m phng qu trnh gia cng bng phn mm Pro/Engineer.

2) Nghin cu cng ngh, ch to mt b khun p v thuc hon chnh trn my phay CNC Concept Mill 155 v my tin CNC Concept Turn 250, ti vin cng ngh c kh v t ng ha - Trng i Hc Bch Khoa - i Hc Nng.

3) Trn c s kt qu trn c th pht trin thit k, ch to hu ht cc loi khun p v thuc c s dng trong cc c s sn xut dc phm hin nay khu vc min trung. 2. HNG NGHIN CU TIP THEO CA TI

Xy dng phng php, trnh t tnh ton thit k v cng ngh gia cng mt khun mu, da trn c s ta c th gia cng cc khun khc theo yu cu ca ngnh sn xut dc phm.

Nghin cu bn, vt liu lm khun mu ph hp vi yu cu ca ngnh sn xut dc phm.

Tuy nhin, nu c iu kin o bin dng, kch thc ca khun c gia cng so snh v chnh xc theo yu cu ca khun thit k cng nh p th c trn thc t th ti c ngha thc t hn.

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