Viet Chap 11 Doa Tinh Tien Ren Trong

Embed Size (px)

Citation preview

  • 7/23/2019 Viet Chap 11 Doa Tinh Tien Ren Trong

    1/22

    Cutting

    To

    olA

    pplications

    Ti liu ny c dch sang ting vit bi:

    T bn gc:https://docs.google.com/file/d/0B2JJJMzJbJcwYTBBZW9TSjhqVGM/edit

    Lin h:[email protected]@gmail.com

    Dch ti liu ca bn:http://www.mientayvn.com/dich_tieng_anh_chuyen_nghanh.html

    https://docs.google.com/file/d/0B2JJJMzJbJcwYTBBZW9TSjhqVGM/edithttps://docs.google.com/file/d/0B2JJJMzJbJcwYTBBZW9TSjhqVGM/editmailto:[email protected]:[email protected]:[email protected]:[email protected]:[email protected]://www.mientayvn.com/dich_tieng_anh_chuyen_nghanh.htmlhttp://www.mientayvn.com/dich_tieng_anh_chuyen_nghanh.htmlhttp://www.mientayvn.com/dich_tieng_anh_chuyen_nghanh.htmlmailto:[email protected]:[email protected]://docs.google.com/file/d/0B2JJJMzJbJcwYTBBZW9TSjhqVGM/edit
  • 7/23/2019 Viet Chap 11 Doa Tinh Tien Ren Trong

    2/22

    Cc chng sp ti

    Loi b kim loiVt liu lm dao tin

    Phng php loi b kim loiKh nng gia cng ca kim loi

    Gia cng im nDao tinng knh ngoi v hot

    ngPhng php tinng knh

    ngoi v my mcTin rnh v to renngoi

    To hnh v nh bng

    Qu trnh to lMi khoan v thao tc khoan

    Cc phng php khoan v my mcThao tc doa th v my mc

    Doa tinh v to ren trong

    Gia cng nhiu imDao phay v cc my mc

    Phng php phay v my mcChut v hot ng chut

    Ca v hot ng ca

    Qu trnh mi mn

    miv cc thao tcPhng php miv my mc

    Mi th v mi tinh(Mi nghin v mi khn)

    Chng11

    Doa tinh v tinren trong11.1 Gii thiu

    Khoan xon khng to cc l khoan tinh v c kch thtchnh xc, cho nn ngi ta thng s dng mt s loi daodoa tinh gia cng kch tht cui cng v hon thnh quytrnh ct. Dao doatinh khng to ra l, n ch m rng l ckhoan hoc c doa th trc . N s ct n 0.0005 "kchthc daov hon thnh n 32 micro inch.

    Mc d dao doa cacbua rn v mi cacbua c nhiu kch

    tht v kiu khc nhau, nhng thng thng, chng u clm bng thp tc cao (HSS). Dao doa kp mnh thngthng cphn loi theo s v kch tht k t, vi kchtht c mt phn inch hoc milimet. Chng c nhiu kch cng knh khc nhau.

    Ren c s dng cho nhiu mc ch v cc ng dngtrong ngnh gia cng kim loi. Chng c s dng gihoc buc cht cc b phn li vi nhau (c vt, bu lng v ai

    c), v truyn ng (vt dn hng di chuyn hp chy daotrn mt my tin). Cc ren cng c s dng cung cphoc kim sot chuyn ng chnh xc (cc trc chnh trnPanme), v s y c hc (vt p nng vt nng).

  • 7/23/2019 Viet Chap 11 Doa Tinh Tien Ren Trong

    3/22

    Chap. 1: Cutting-Tool Materials

    Khi nh ngha ren, ngi ta phi xt hai nh ngha ring bit l ren ngoi (vt hocbu lng) v ren trong (ai c).

    Ren ngoi l mt mnh vt liu hnh tr c mt rnh xon c u hoc c hnhthnh xung quanh n. Ren trong c nh ngha l mt ming vt liu c mt rnh xon

    c xung quanh phn bn trong ca l hnh tr. Chng ny s tho lun v ren trong vtapping, mt thao tc to ra cc ren trong.

    11.2 Doa tinh

    Doa tinh c nh ngha nh mt qutrnh gia cng c s dng mt dao tin c rnhxon nhiu li ct lm mn, m rng haychnh xc ha kch thc ca l c. Doa tinhc thc hin bng cc loi my ging nhkhoan.

    Dao doa l mt cng c ct quay vi mthoc nhiu yu t ct c s dng m rngkch thc v ng vin l c hnh thnhtrc . Phi s h tr cho n trong qu trnh giacng. Thao tc doa tinh c biu din trong hnh11.1.

    11.2.1 Danh mc dao doa

    Cu toc bn v danh php ca dao doac biu din trong hnh 11.2. Hnh minhha cho thy cc loi dao c s dng nhiu nht cho cc l ln n 1", c gi l daodoa kp mnh.

    Dao doa rn hu nh thc hin tt c quy trnh gia cng vi mt trc c vt 45. Cc rnh dn hng cho dao doa v ci thin phn no quytrnh ct tinh. V vy, daodoa khng nn c s dng di chuyn (ly i) nhiuvt liu.

  • 7/23/2019 Viet Chap 11 Doa Tinh Tien Ren Trong

    4/22

    Chap. 1: Cutting-Tool Materials

    4 Tooling & Production/Chapter 1 2001 www.toolingandproduction.com

    Trc(axis): trc l ng thng tng tng m qua dao doa quay gia cc tm.

    cn(back taper): cn l mt s st gim nh ca ng knh, t trc ra sau

    dc theo chiu di rnh ca dao doa.Thn (Body): thn l: 1) phn ng knh y ca dao doa, bao gm cnh vt

    (chamfer), cht khi ng v gc vt (bevel), 2) cc thnh phn ch yu cho mt tphp cc li dao doa, thng bao gm c chui (cn dao, shank).

    Cnh vt(chamfer): Cnh vt l phn ct gc u vo ca dao doa.

    Chiu di cnh vt (chamfer length): chiu di cnh vt l chiu di ca cnh vtc o song song vi trc ti li ct.

    Gc h cnh vt(Chamfer Relief Angle): Gc h cnh vt l gc h ng trc gcngoi ca cnh vt. N c o bng cch chiu vo trong mt phng tip xc vi phnngoi vi gc ngoi ca cnh vt.

    Khong h (Clearance): Khong h l khng gian c to ra bi khe h pha saului ct hoc mp dao doa.

    Hnh 11.2: Cu trcv danh php ca dao doa gia cng kiu rnh thng.

  • 7/23/2019 Viet Chap 11 Doa Tinh Tien Ren Trong

    5/22

    Chap. 1: Cutting-Tool Materials

    Lui ct(cutting edge): Lui ct l cnh pha trc ca khong ct rnhtheo hngquay khi gia cng.

    Cc rnh (Flutes): Cc rnh l cc khe dc c hnh thnh trong thn ca dao doang vai tr l li ct, cho php chip i qua, v cho php cht lng ct n li ct.

    Chiu di rnh xon (Flute length): chiu di rnh xon l chiu di ca cc rnhxonkhng k n phn chui dao (cn dao).

    Khong ct rnh(land): khong ct rnh l phn ca dao doa gia cc rnh lin k.

    Mp (Margin): mp l phn khng h ca phn ngoi vi ca khong ct rnh tipgip vi li ct.

    C(neck): C l phn ng knh gim li ni chui vi thn, hoc kt ni cc phn

    khc nhau ca dao doa.Chiu di ton phn (Overall Length): chiu di ton phn l chiu di cc i ca

    ton b dao doa t u ny n u kia, nhng khng bao gm cc tm bn ngoi hoc cvt ni rng.

    Chui (Shank): chn l mt phn ca dao doa gi v iu khin dao.

    Chui thng(Straight shank): Chui thng l chui hnh tr.

    Chui cn (taper shank): chui cn l mt chui c to ra khp mt ng nicn c bit (hnh nn) .

    11.2.2 Cc loi ca dao doa

    Dao doa c ch to vi ba hnh dng rnh v tt c l tiu chun.

    Cc rnh thng: Cc dao doa rnh thng thch hp cho hu ht cng vic v t tn km nht,nhng khng nn s dng nu c nhng ng ni rnh an xen hoc s gin on khctrong l.

    Xon c tay phi: Dao doa rnh xon c phi to iu kin cho thao tc gia cng t do hnv c xu hng nng chip ra khi l. Khng nn s dng chng gia cng ng hocnhm mm v nhng dao doa ny c xu hng ko vo l.

    Xon c tay tri: Dao doa rnh xon c tri i hi nhiu p lc hn tin, nhng c thct mn v c th c s dng gia cng cc vt liu mm, dnh, bi v chng c khuynhhng y ra t lkhi tin. ng s dng cc dng c ny gia cng cc l cn (khngc li ra) v chng y chip vo l.

  • 7/23/2019 Viet Chap 11 Doa Tinh Tien Ren Trong

    6/22

    Chap. 1: Cutting-Tool Materials

    6 Tooling & Production/Chapter 1 2001 www.toolingandproduction.com

    Tt c cc dao doa c s dng to ra cc l trn tru v chnh xc. Mt s c iukhinbng tay, v mt s khc c iu khinbng my.

    Dao doa my

    Doa my c s dng trn my khoan v

    my tin gia cng th v tinh. Dao doamy c nhiu loi nh chui hnh cn ,hoc thng, v cc rnh thnghay xon c.Dao doa chui hnh cn (hnh 11.4) khptrc tip vo trc chnh, v dao doa chuithng, thng gi l dao doa kp mnh,khp vo trong my khoan.

    Dao doacu(Rose Reamers): dao doa cu

    l mt loi dao doa my ch ct cnh vt450(gc vt) c t trn mi.Thn cadao doa cu mng manh (khong 0.01 inchtrn inch chiu di chng dnh trongqu trnh gia cng. Dao doa ny khng ctmt l trn tru v ni chung c s dng

    lm l di c vi phn nghn inch. Bi v dao doa cu gia cng mt l di kch tht

    danh ngha0.001 n 0.005 inch, dao doa tay c s dng ct tinh l n kch thtcn thit. Tt c cc dao doa tay c chui hnh vung v khng c s dng v thao tcvi my.

    Dao doa c rnh: Dao doa c rnh l cc dao doa my c s dng hon thnh lkhoan. Loi dao dao ny loi b kim loi t hn so vi dao doa cu. Dao doa c rnh cnhiu li ct hn dao doa cu v do c th gia cng mt l trn tru hn. Cc dao doa crnh ct trn ct u b vt hoc cc mt bn. Chng cng c sn di dng cacbua rnhoc cc tm lt cacbua cho rng ct.

    Dao doa cn lp(Shell reamer): Dao doa cn lp gm hai phn: u doa v cn lp. Khi sdng, u doa c gn trn cn lp. u doa c th thuc loi hnh cu hoc c rnh. Cn

    Hnh 11.4: Dao doa chuihnh cn rnh thng micacbua. (Vi s gip ca: Cn c ct Morse

    Hnh 11.3: Phng php xc nh daodoatay tri v tay phi.

  • 7/23/2019 Viet Chap 11 Doa Tinh Tien Ren Trong

    7/22

    Chap. 1: Cutting-Tool Materials

    c th thng hoc hnh cn. Dao doa cn lp c quan tm v n c nhiu li ch, bi vch cn thay u doa khi n b mn hoc h hng.

    Dao doa tay

    Dao doa tay l dao doa tinh c nhn bit qua hnh vung trn chui ca chng. Chngc iu khin bng tayvi mt tay quay khp vo hnh vung ny (xem hnh 11.7). Loimi doa ny ch ct bng cc li ct bn ngoi. u ca dao doa tay c vut hi nhn d nh hng trong lkhoan. Chiu di ca cn thng bng ng knh ca dao doa.

    Khng c quay dao doa tay bng in v phi khi ng n ng v chnh xc. Chngkhng nn loi b hn 0,001 "n 0,005" vt liu. Dao doa tay c ng knh t 1/8 "nhn 2 inchv thng c lm bng thp carbon hoc thp tc cao.

    Dao doa tay hnh cn: dao doa tay hnh cn l dao doa tay c ch to doa mi cnkch thttiu chun. Chng c dng gia cng cc l hnh cn th hoc tinh. Cngging nh dao doa tay thng, loi dao doa ny nn c s dng cn thn v khng nniu khin bng my.

    Dao doa iu chnh c(hnh 11.8a): dao doa iu chnh c s dng to ra l btk kch tht no trong phm vi ca dao doa. Hai ai c iu chnh t ti mi u ca li

    Hnh 11.5: Cn lp cng vi hai u doa, mt HSS v mt loi micacbua khc. (Vi s gip ca: Cng c ct Morse)

    Hnh 11.6: Dao doa tay hng tri xon c,dao doa tay chui vung khng th c iukhin in. (Vi s gip ca: ClevelandTwist khoan Greenfield Industries)

  • 7/23/2019 Viet Chap 11 Doa Tinh Tien Ren Trong

    8/22

    Chap. 1: Cutting-Tool Materials

    8 Tooling & Production/Chapter 1 2001 www.toolingandproduction.com

    dao di chuyn li ny. Dao doa tay iu chnh c c ng knh t n 3 inch.Mi dao doa c khong iu chnh c 64 inch trn v di ng knh danh ngha ca n.

    Doa doa tay m rng(hnh 11.8 b): dao doa tay m rng ging nh dao doa tay iu chnhc nhng c khon iu chnh gii hn 0.010 inch. Dao doa tay m rng c c iu

    chnh u ca n. Khi xoay, c iu chnh ny p vo cc nt cn bn trong ca dao doa,m rng ng knh ca n. Dao doa m rng cng c loi dng cho my.

    Mt s ch v dao doa:

    V dao doa l cc cng c ct tinh chnh xc, chng ta nn dng chng cn thn:

    Cc dao doa cn c ct gi trong tng hp ring bit trong hp ng dao trnhnh hng n li ct.

    Trong qu trnh doa tinh lun dng cht lng ct, ngoi tr khi gia cng gan.

    Khng c quay ngc dao doa, nu khng li ct s b cn.

    G hoc kha trn li ct phi c di chuyn i bng mi tidu trnh ctl qu kh.

    11.2.3 iu kin vn hnh

    Trong qu doa tinh, tc v bc tin rt quan trng, vic loi b vt liu v s nhhng phi c xem xt to c cc lkhng vt nt.

    Tc doa tinh: Tc doa tinh bng my c th thay i ng k ph thuc mt phn vocc vt liu c doa, loi my, chnh xc v s hon thin cn thit. Ni chung hu htdoa tinh bng my c thc hin tc khong 2/3 tc khoan trn cng vt liu.

    Bc tin doa tinh: Bc tin doa tinh thng cao hn nhiu so vi khoan, thng chy t200 n 300% bc tin khoan. Bc tin qu thp c th dn n mi mn dao doa qumc. Lc no bc tin cng phi cao cho php dao doa tinh ct ch khng phi ch

    Hnh 11.8: (a) Dao doatay iu chnh c. (b)Dao doa m rng cchn vung. (Vi sgip ca: Cng cct Morse)

  • 7/23/2019 Viet Chap 11 Doa Tinh Tien Ren Trong

    9/22

    Chap. 1: Cutting-Tool Materials

    xt hoc nh bng. Bc tin qu cao c th lm gim chnh xc ca lv gim chtlng ca quy trnh ct tinh. tng c bn l s dng tc cao n mc c th v vncn to ra c chnh xc v cht lng ct tinh cn thit.

    Vt liu c ly i: Vi cng mt l do, vt liu khng cho doa tinh c th dn n snh bng ch khng phi ct. Tht kh khi qut ha v giai on ny v n c linquan cht ch vi cc loi vt liu, bc tin, mc hon ho c yu cu, su cal v kh nng chip ca dao doa. i vi dao tinh bng my. 0.010 inch trn l inch,0.015 inch trn l inch, ln n 0.25 inch trn l 1 n inch c v l im khi u tt.i vi doa tinh bng tay, phm vi di chuyn vt liu c php nh hn nhiu, mt phnv c kh khn trong vic buc dao doa i qua vt liu. Phm vi cho php thng thng t0.001 inch n 0.003 inch.

    S nh hng: Trong thao tc doa tinh l tng, tt c cc b phn nh trc chnh, daodoa, ng lt, v l c gia cng phi nh hng hon ho. Bt k s thay i no so vixu hng ny cng tng mi mn ca dao doa v lm gim i chnh xc ca l. Lnhn kiu hnh cn, qu kh, hoc hnh chung c th l do nh hng khng tt. i khinhng tc ng xu ca vic nh hng sai lch c th c gim thng qua vic s dngcc holeder t la hoc iu chnh c. i khi nu ngi s dng mi dao doa tinh nc cn nh cng c th gip khc phc nh hng ca s sai lch.

    S rung ng: S rung ng xut hin trong thao tc doa c th nh hng xu n tui th

    dao v s ct tinh l. Rung ng c th l kt qu ca mt s nguyn nhn, chng hn nh:

    * Tc qu ln.

    * Qu nhiu khong h trn dao doa.

    * Thiu vng trong khun hoc my.

    * Khng an ton trong t chc cng vic.

    Hnh 11.7: Tay quay c s dng gi dao doa tay ct tinh l khoan. (Vi s gip ca: Cleveland Twist khoan Greenfield Industries)

  • 7/23/2019 Viet Chap 11 Doa Tinh Tien Ren Trong

    10/22

    Chap. 1: Cutting-Tool Materials

    10 Tooling & Production/Chapter 1 www.toolingandproduction.com

    * S nh ra qu nhiu ca dao doa hoc trc chnh.

    * Phi qu nh.

    11.2.4 Thao tc doa tinh

    Thao tc doa tinh c th c thc hin trn my tin, khoan v cc cm u my.Doa tin: Doa tinh trn mytin ch c th c thc hin bng cch gia dao doa v tr sau hoc trong u khoan i vi dao doa chui thng hoc trc tip trong trc sau ivi dao doa chui hnh cn (xem hnh 11.4). Phi c gia cng c th c gi trongngm hoc dn trn tm phng. Trong trng hp my tin rvonve, dao dao ch c thc dng trong turret lc gic.

    i khi, cc reamer c gi trong cc holder t la trong sau. Nhng holder ny

    cho php dao doa t ng tm trn l c khoan trc . Cc l su (ln hn ba lnng knh khoan) c khuynh hng chy ra ngoi. Dao doa s khng chnh xc trongiu kin ny v l phi c doa nu s nh hng quan trng.

    Doa my khoan: doa trong my khoan cng i hi dao doa c gi ng trc vi mtu khoan (drill chuck) i vi cc dao doa my chui thng, hoc trc tip trnn trc vidao doa chui hnh cn (xem hnh 11.4). Phi c gia cng c gi trong mt bn kp vc chnh tm trn bn khoan.

    Doa tinh trn my tin c thc hin bng cch quay phi v gi dao ng yn,trong khi doa tinh trn my khoan c thc hin bng cch quay dao doa v gi phing yn. Cc u t la c th c dng trn my khoan cng nh my tin.

    Hnh 11.9: Thaotc tin ren trongt ng in hnhvi b t ongc. (Vi sgip ca:Tapmatic Corp)

  • 7/23/2019 Viet Chap 11 Doa Tinh Tien Ren Trong

    11/22

    Chap. 1: Cutting-Tool Materials

    Doa tinh cm u my: Doa tinh trn cm u my kh ph bin. Cc dao doa thng cgi trong turret lc gic hoc trong n cng c t ng. Cc cch b tr thng phc tphn trong khi tc v bc tin c lp trnh trc.

    11.3 To ren trong

    To ren trong c nh ngha l: Mt qu trnh to ra cc ren bn trong bng cch s dngmt cng c (dao tin ren) c rng ngoi vi ca n to ra cc ren bn trong l ckhoan. Chuyn ng quay v dc theo trc kt hp gia dao tin ren v phi hnh thnh nncc ren.

    11.3.1 Danh mc dao to ren

    Cc ren c nhiu kch thc khc nhau.Trong gia cng hin i, chng ta cn phi c kinthc thc t v cc thut ng v ren. Renthun l ren i hi phi quay sang phi hoc

    Hnh 11.10: Danh php dao tin

    ren v ren.

  • 7/23/2019 Viet Chap 11 Doa Tinh Tien Ren Trong

    12/22

    Chap. 1: Cutting-Tool Materials

    12 Tooling & Production/Chapter 1 www.toolingandproduction.com

    theo chiu kim ng h sit cht n. Ren nghch l ren i hi phi quay sang bn trihoc xoay ngc chiu kim ng h sit cht n. "Khp ren" l khon cht hoc lnglo gia cc ren n khp bn ngoi v bn trong. "Chui ren" l mt nhm ng knh v

    bcc phn bit vi nhau qua s ren trn mt inch c p dng cho mt ng knhc th. Hai chui ren c s dng ph bin trong ngnh cng nghip l chui th v tinh,

    c k hiu l UNC v UNF. Danh mc dao to ren c trnh by bn di.

    Cnh vt(Chamfer ): Cnh vt l s thun nhn ca cc ren u trc ca mikhong ct rnh ca dao ct ren tinh, dao ct ren trong, hoc die (mt loi dao tin c nhiul, phi a vocc l s c to ren) qua vicct b v lm gim chp ca vi rngu tin phn phi thao tc ct trn vi rng.

    Chp (Cr est): Chp l b mt ca ren ni sn ren v cch xa nht hnh tr hochnh nn m ren nh ra t n.

    Sn(Flank): Sn l phn ca b mt ren xon c ni chp v chn, v v mt lthuyt n l mt ng thng trong phn mt phng ng trc.

    Rnh(F lute): rnh l cc khe dc c hnh thnh trong dao tin rnh to ra ccli ct trn bin dng ren v cung cp khng gian chip v cho cht lng ct i qua.

    Gc un cong(Hook Angle): gc un cong l gc nghing ca mt mt lm, thngc chia thnh "un cong dy" hoc "un cong tip tuyn."

    Khong ct rnh(land): Khong ct rnh l mt trong cc phnc to ren giacc rnh ca dao tin ren.

    Bc ren(Lead of Thr ead): Bc ren l khang cch m mt ren tin ng trc vtrc trong mtvng hon chnh. Trn dao tin ren mt u mi, bc (lead) v khu (pich) ging nhau. Trn dao tin ren nhiu u mi, bc ren bng nhiu khu .

    ng knh ln(M ajor Diameter ): y l ng knh ca hnh tr hoc hnh nnln, ti mt v tr nht nh trn trc tip gip vi chp ca ren ngoi hoc chn ca ren

    trong.ng knh nh(M inor D iameter): ng knh nh l ng knh ca hnh tr

    hoc hnh nn nh, mt v tr nht nh trn trc tip gip vi chn ca ren ngoi hoc ccchp ca mt ren trong.

    ng knh hiu dng(Pitch diameter ): ng knh hiu dng l ng knh ca mthnh tr hoc hnh nn o, ti mt im nht nh trn trc ng knh nh th v v tr catrc ca n, b mt ca n s i qua ren theo kiu no lm cho sn ren v rnh ren

  • 7/23/2019 Viet Chap 11 Doa Tinh Tien Ren Trong

    13/22

    Chap. 1: Cutting-Tool Materials

    bng nhau, v nh vy, c nm cch u gia cc hnh tr hoc hnh nn ln hoc nh rnt ca mt dng ren nht nh. Trn mt ren hon ho v mt l thuyt, cc rng ny

    bng mt na khu c bn (o song song vi trc).

    im xon c(Spiral Point): im xon c l s xoc gc trong mt ct ca khong

    ct rnhti u vt. N to mt gc vi trc ca dao tin ren i din vi trc quay. Chiudi ca n thng ln hn chiu di cnh vt v gc ca n i vi trc dao tin ren thngc to ln hng chip v trc dao tin ren. Dao tin ren c th c hoc khng ccc rnh dc.

    vung (Square): vung l bn mt phng iu khinsong song vi trc trn chn daoto ren hnh thnh nn vung hoc vung vi gc trn.

    11.3.2 Cc loi dao tin ren

    Hnh 11.11: Mt s kiu v hnh dng dao tin ren trong. (Vi s gip ca: Greenfield Industries)

  • 7/23/2019 Viet Chap 11 Doa Tinh Tien Ren Trong

    14/22

    Chap. 1: Cutting-Tool Materials

    14 Tooling & Production/Chapter 1 www.toolingandproduction.com

    Cc dao tin ren tay: Ngy nay dao tin ren tay c s dng c bng tay v trong tt ccc loi my. y l thit k dao tin ren c bn: bn rnh thng, dng u vi hoc y.Kch thc inh vt nh c nh sl tiu chun trong hai v ba rnh, ty thuc vo kchthc.

    Nu cn gia cng kim loi mm v dai, hoc gia cng cc l ngang, cn phi s dnghai hoc ba dao tin ren trong rnh xon kch thc ln hn. Cc khng gian rnh ln hn,nhng dao tin ren trong yu hn. c bit loi hai rnh c tit din rt nh.

    Chip c hnh thnh bi nhng dao tin ren ny khng th ra ngoi, do , chngtch ly trong cc khng gian rnh xon. iu ny gy ra thm ma st v l nguyn nhnchnh lm dao tin b hng.

    Dao tin ren trong mi xon c: dao tin ren trong mi xon c hoc "sng" cch to ging nh dao tin ren tay chun ngoi tr mi ca n. Mt du gch cho l nntrong mi rnh xon c ti mica dao tin ren trong. iu ny km theo mt vi iu:

    * Dao tin ren trong kiu sng c t rnh xon (thng l ba), v chng thng nng hn.iu c ngha l dao tin ren trong mnh hn.

    * Cc chip b p i v trc dao tin ren thay v tch ly trong cc rnh xon, nh dao tinren plug.

    * Do hai yut ny, dao tin ren trong mixon c thng c th chy nhanh hn dao tin

    ren tay, v gim gy dao ng k.

    Trong nhiu trng hp, dao tin ren sng c thay th bng dng tiu chun trongcng nghip, c bit l cho cc l trng u h trong thp v nhm nh. C hai loi d aotin ren thng thng v mixon c c ch to mi kch tht, c c theo n v mt.

    Dao tin ren trong rnh xon c: dao tin ren y rnh xon c c ch to theokiu thng thng v xon c nhanh, tc l, vi gc xon ln hay nh. i khi chng cgi l dao tin ren trong "rnh xon c". Nhu cu s dng cc loi dao tin ren trong ny

    tng ln ng k v chng y chip ra khi lv to ra cc ren tt khi gia cng kim loimm (v d nh nhm, km, v ng),nhng cng lm vic tt trong kim loi Monel, thpkhng g v thp c. Chng c ch to mi kch tht ln n 1 1/2 "v theo n vmt ln n 12 mm.

  • 7/23/2019 Viet Chap 11 Doa Tinh Tien Ren Trong

    15/22

    Chap. 1: Cutting-Tool Materials

    Khi cc dao tin ren tiu chun khng gia cng hiu qu, nu c nhiu nhm, ng, ganghoc thp khng g cn to ren trong, cc nh sn xut c th cung cp cc loi dao chuyndng "tiu chun" s lm vic tt hn.

    Dao tin ren ng: Dao tin ren ng a nng c s dng to ren cho nhiu loi kim loic cha st v khng cha st. Tt c dao tin ren ng c cung cp vi cnh vt ren 2 1/23 1/2. Kch thc danh ngha ca dao tin ren ng l kch tht ca ng khp c to rentrong, ch khng phi kch thc thc ca dao.

    Hnh 11.12: (a) Dao tin ren trong mixon c c thay thbng dao tin ren trong 'tiu chun' trong nhiu trng hp. (b)Dao tin ren trong y rnh xon c (Vi s gip ca: Cngc ct Morse).

  • 7/23/2019 Viet Chap 11 Doa Tinh Tien Ren Trong

    16/22

    Chap. 1: Cutting-Tool Materials

    16 Tooling & Production/Chapter 1 www.toolingandproduction.com

    Dao tin ren ng ren mi l tiu chun theo American Standard Pipe Form (NPT) vAmerican Standard Dryseal Pipe Form (NPTF). Cc ren NPT cn dng mt cht hn nh

    bng Teflon, hoc hp cht ng. Dao tin ren ai c c s dng to ren cc ch khpto ra ch ni cht m khng dng cht hn.

    Dao tin renkhng xon c: Dao tin ren khng xon c (Hnh 11.14) khng ging cc daotin ren, ngoi tr cc ren xon c. Cc dao tin ren ny khng trn. Chng c to hnh gia cng ngi kim loi t vch lthnh dng ren khng c chip. Dao tin ren khngxon c ban u c thit k s dng trong cc hp kim nhm, ng v km. Tuynhin, n ang c s dng thnh cng trong thp nh v mt s loi thp khng g. Vvy, rt cn kim tra s dng ni BHN di 180. Chng c sn nhiu kch c, baogm c cc ren theo n v mt.

    Loi dao tin ren trong ny rt mnh v c th gia cng nhanh gp hai ln cc loi khc, tuynhin, kch tht ca l trc khi c to ren phi khng ln hn ng knh khu (pitch diameter) ca ren.To ren lnh thngc ct tinh tt hn v ct ren mnh hn. Cn

    phi s dng du ct, v hai ul cn c khot bi v dao to ren lm tung kim loi ln c hai u.

    Cc dao tin ren ng knh thay i c: Cc dao tin ren ny co nh ng knh li khin cui qu trnh ct. V vy, khi c s dng trn b t k my tin no, chng c th

    Hnh 11.13: Dao tin ren trongng rnh xon c v tay quaykiu T. (Vi s gip ca:Cng c ctMorse)

  • 7/23/2019 Viet Chap 11 Doa Tinh Tien Ren Trong

    17/22

    Chap. 1: Cutting-Tool Materials

    c ko tr li nhanh chng. Chng c ch to vi kch tht ln n 1 inch, trong ccc ren my v ng. Chng s dng 3-6 "dao tin ren" ring bit phi c mi nh mt tphp. Holder dao tin ren v cc die c bit lm cho t hp ny tng i t tin, nhngn l kinh t cho cng vic sn xut trung bnh v cao.

    11.3.3 Cc ty chn hot ng

    Mt s ren, c ngoi v trong, c th c ct vi mt cng c im n nh c chngminh trc y. Tuy nhin, ngi ta thng s dng die hoc dao tin ren trong v nnhanh hn v chnh xc hn.

    Dao tin ren trong c ch to vi nhiu kiu, nhng mt vi kiu thc hin 90% cngvic. u ct ca dao tin ren trong c thchin trong ba cn khc nhau.

    "Dao tin ren dng cn" khng thng xuyn c s dng ngy nay. Thnh thong, nc s dng ct th nu kim loi kh tin ren trong. u c vt nhn khong 5 cho mi cnh, to ra tm ren tng phn.

    Hnh 11.14: Daotin ren trong khngxon c gia cnglnh cc ren. (Vi

    s gip ca:Cng ty cng cWeldon)

  • 7/23/2019 Viet Chap 11 Doa Tinh Tien Ren Trong

    18/22

    Chap. 1: Cutting-Tool Materials

    18 Tooling & Production/Chapter 1 www.toolingandproduction.com

    "Dao tin ren u" l kiu dao c dng c l khong 90% thi gian. Vi dng hnh hcthch hp ca li ct v cht bi trn tt, dao tin ren u thc hin hu ht cc cng viccn thit. u c vt nhn 8 trn mt cnh, to ra bn hoc nm ren khng honchnh.

    "Dao tin ren y" ch c s dng cho cc l cn trong ren phi chy xung ti gny l. N ch c 1 1/2 n 3 lkhng hon chnh. Nu l c th c khoan su hn,khng cn dng dao tin ren y. Dao tin ren u phi c s dng u tin, tip theo l

    dao tin ren y.

    Tt c ba loi dao tin ren cui c to t cc cn ging nhau. Kch thc, chiu di, vtt c cc php o tr cn u ging nhau.

    Vt liu dng cho dao tin ren trong thng l thp tc cao trong M1, M2, M7 v ikhi thp tc cao coban seri M40. Mt vi dao tin ren trong c lm t cacbua vonframrn.

    Hu ht dao tin ren ngy nay c ren mi. Vic mi c thc hin sau khi lm cng vlm cho cng c ct chnh xc hn nhiu. Dao tin ren trong "Ct ren" c sn trn thtrng vi gi thnh thp vi mt s kiu mu v kch tht.

    11.3.4 Cc thao tc tin ren trong

    Cng ging nh thao tc doa tinh, tin ren trong c thc hin trn my tin, khoan v cccm u my.Mt thao tc tin ren trong nhiu ltrn mt chi tit c biu din tronghnh 11.16.

    Hnh 11.15: Cm dao tin ren thu

    nh t tin hn nhng kinh thn cho cc hot ng sn xuttc cao v trung bnh. (Vi sgip ca: GreenfieldIndustries)

  • 7/23/2019 Viet Chap 11 Doa Tinh Tien Ren Trong

    19/22

    Chap. 1: Cutting-Tool Materials

    Mi khoan lren: R rng, cc dao tin ren y khng th ct lring ca chng.Do , mt l kch thc thch hp phi c to ra trc khi dao tin ren trong c sdng. Thng thng, l ny c khoan.Mi khoan l ren khng phi l mt loi mikhoan c bit. Mi khoan lren ch l mt cch thun tin cp n vic khoan kchtht thch hp trc khi dng dao tin ren trong. Kch tht mi khoan l ren da trn75% ren c cho trongcc bng tham kho. Hin nay trong nhiu cng ty, tit kimdao tin ren trong, thi gian v ph phm, ngi ta s dng 60 n 65% ren xc nh

    kch thc mi khoan l ren. Cc mi khoan v thao tc khoan c tho lun trongchng 9. S kt hp gia mi khoan v dao tin ren trong c biu din trong hnh 11.17v c s dng thc hin ng thi c hai thao tc v tin ren trong.

    Hnh 11.16: Thao tc tin ren trong t ng trn mt chi tit. (Vi s gip ca: Tapmatic Corp)

  • 7/23/2019 Viet Chap 11 Doa Tinh Tien Ren Trong

    20/22

    Chap. 1: Cutting-Tool Materials

    20 Tooling & Production/Chapter 1 www.toolingandproduction.com

    Lc to ren cng su hn, thi gian khoan v to ren trong cng di v daotin ren trong cng ckh nng b gy.Nu c qu t ren gi bu lng, cc ren s ln. Mt sni no gia c chiu su bt khp ren cc tiu gi cho bu lng gy trc khi renh. y c gi l chiu su ti u. Khoan to ren trong phi su trong cc lcn cho php t hai n nm ren vt nhn trn dao tin ren trong cng vi khong trng chip,

    cng vi im khoan.Holder cng c: Holder cng c tin ren trong bng tay c gi l 'tay quay'Chng ging nhau i vi c dao tin ren trong v dao doa (xem hnh 11.7 v hnh 11.13.),

    bi v hu ht cc dao tin ren trong c chui vung. Tay quay c th iu chnh c v cth c s dng cho mt s kch tht khc nhau ca dao tin ren trong. Khi cc dao tinren trong c s dng trong my khoan hoc cc cm u my, mt b ly hp loi trt,c mt u o ngc c s dng. Nhng u tin ren trong ny(Hnh 11.18) c thc thit lp nu gp phi mt vt knh trong kim loi, b li hp trt v dao tin rentrong s khng gy. Chng c thit k sao cho khi tay vn hoc chu trnh my iukhin s bt u hung ln, s quay s o ngc (v thng nhanh hn) a dao tin

    ren an ton ra khi l.

    Hnh 11.17: Dao tin kt hp khoan v tin ren trong c sdng cho khoan v tin ren trong mt ln i qua (Vi s gip ca: Cng c ct Morse)

    Hnh 11.8: Ccu dao tinren trong c

    bit vi loio ngc,trt c sdng trongmy khoan v

    cc cm umy. (Vi sgip caTapmaticCorp)

  • 7/23/2019 Viet Chap 11 Doa Tinh Tien Ren Trong

    21/22

    Chap. 1: Cutting-Tool Materials

    S kp cht: S kp cht cho tin ren trong ging nhau i vi mi my khoan hocmy tin: kp, m kp, v.vl cn thit. cn phi nh v dao tin ren trong ng tm vhng thng vo l. iu ny kh khn trong tin ren tay nhng tng i d trong tin ren

    bng my. iu khin s c bit c hiu qu, v n s nh v trn mt l, bt k khi nc khoan, nu n c khoan t cng mt loi dao tin ren trong v cng mt cch b

    tr. Tin ren im n c tho lun trong chng 6. S ct ren hoc to ra ren ngoi cngc thc hin vi cc die v cc u ct ren t m . Hnh 11.19 cho thy mt s u diev dao ren khun c s dng to ren ngoi.

    Bi trn: Cc li ct c dao tin ren trong v die c chn vi trong vt liu, dubi trn kh cn thit. i vi nhm, du m c s dng, cc kim loi khc cn nhngloi du bng luhunh, i khi c th l cc loi du clo ha. Hnh 11.20 biu din thaotc tin ren trong vi mt h thng nh lng cht lng t ng cho cc cm u my.n v Automiser c biu din y nh lng cht bi trn / lm mt qua u tin rentrong mt cch t ng, trong khi u trong trc quay ca my. Cc hp kim ng c

    nhum mu bng lu hunh, v vy cn phi s dng du khong hoc du ha tan. Gangthng tin ren m khng cn cht bi trn. C mt s cht lng tng hp dng cho tinren trong trn th trng ngy nay. Chng hi t hn nhng chng c th to ra cc ren tthn v dao t gy hn.

    Hnh 11.19:Ct ren ngoi

    c thc hin vi ccdie v u ct ren t m .(Vi s gip ca:Greenfield Industries)

  • 7/23/2019 Viet Chap 11 Doa Tinh Tien Ren Trong

    22/22

    Chap. 1: Cutting-Tool Materials

    Hnh 11.20: Thao tc tin ren trong Multihold vi h thnglm mt / bi trn t ng. (Vi s gip ca: TapmaticCorp)