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  1. UY BAN NHAN DAN QU4N 5 TRUONGTRUNGCAPNGHEKYTHU4TCONGNGHtHUNGVUONG , ' GIAOTRINH Khi nen - Thu)' l\fC ' , Nghe: Cat gQt kim lo~i TRINH DO• TRUNG CAP TPHCM-2019
  2. 1 LOIMOBAU V&i S\f phat tri~n cong ngh~ hi~n nay, di_ic bi~t la trong linh V\fC t\f dqng boa thi di~n khi nen, khi nen, thiiy l\fc va nhfrng rrng dl}.ng dong m
  3. 2 ' .,. ,. MlJC LlJC LOI MO DAU .......................................................................................................... 1 CHUONG I: KHA1 NIEM VE KHi NEN VA UNG DUNG CUA KHi NEN .. 4 1. sv PHA.T TRI@N CuA Ky THU~T KHi NEN ........ ~ ...................................... 4 IL NHuNG D~C TRUNG CuA KHONG KHi NEN .......................................... 4 111.D!C TiNH CUA KHi NEN ........................................................................... 6 IV. cAc Di;\.1 LUONG V!TLY .................................................................... 6 V. KHA NANG UNG Dl)NG CUA KHi NEN ................................................ 10 1. Trang li'nh vvc di Su khi@n ............................................................................. 10 2. H~ th6ng truySn d(:mg .................................................................................... 10 VI. VU NHUdC DIEM CUA HE THONG TRUYEN DONG BANG KHi NEN .............. :............................. :...................................... :........................... 10 · 1. Vu di@m ................................................................................................ 10 2. Nhuoc di@m .......................................................................................... 11 VIL cAc LON MAY KHi NEN VA THIET BJ XU LY KHi NEN ........... 11 1. May nen khi: ......................................................................................... 11 2. Thi@t bi xu ly khi nen ............................................................................ 12 3. Cac ph~n tu ch§.p hanh (working elements) ........................................... 14 C~UONG II: THIET KE, LAP DJT VA V4N HANH H¥ THONG KHi NEN ....................................•.......................................•....•......................................• 17 1. cAc LON VAN KHi NEN ......................................................................... 11 1. Ky hi~u chung cua van diSu khi@n dao chiSu (Directional control valve) ......................................................................................................... 17 2. Cac van dao chiSu di Su khi@n b&ng khi nen ........................................... 19 11. cAc LON v AN LOGIC ............................................................................. 23 1. Van logic AND ( Dual Pressure Valve - AND Function) ( Hinh 2.29) .. 23 2. Van logic OR (Shuttle Valve - OR function) (Hinh 2.30) ................... 24 3. Van m
  4. 3 1. Di@u khiSn tv d9ng theo ap suit ............................................................ 41 2. f)i@u khiSn theo t~ng ............................................................................. 41 CHUONG , , IV: LAP l>~T, V4N HANH VA KIEM TRA Hlj: THONG l>Ilj:N -KHI NEN .............................................................................................................. 55 I. KlIAI NI$M .................................................................................................. 55 II. DlNHLU,ATOIIM ....................................................................................... 55 III.NUT NHAN .................................................................................................. 57 IV. VALVEDISNTV................................................................................... 57 V. RELAY ......................................................................................................... 62 VI. CONG TAC HANH TRINH ................................................................... 65 VII. RELAY THOI GIAN .............................................................................. 69 VIII. CONG TAC AP SUAT ··········································································· 72
  5. 4 . VE KHi NEN VA UNG DUNG CHUONG I: KHAI NIEM . CUA KHiNEN Gi6i thi~u: Trong chuang nay se cho nguai h9c c6 nhung kiSn thuc, khai ni~m vS khi nen va nhfrng ung dvng trong h~ th6ng tv d9ng h6a, CO' di~n tu. Muc tieu: ~ Nim ro cac quy dinh trong h'.ic thvc hanh cung nhu cac n9i quy an toan lao d9ng. - BiSt duqc m9t s6 d~c diSm h~ th6ng truySn d9ng bing khi nen. - Cong thuc tinh toan va CO' so cua h~ th6ng kin nen - Nh~n d~ng duqc cac thiSt bi cong nghi~p. I. S\f PHA.T TRI~N CiiA Ky THUiT KHi NEN Nhu chung ta da bi@t, khong khi nen la m9t d~ng nang luqng cu ma con nguai da SU dvng thay th@ cho cac Ive CO' h9c. Tu hang ngan nam tru6c, khong khi da nen dSn muc c6 th@ chay duqc. N6 con la m9t trong b6n phAn tu CO' ban duqc thua nh~n boi nguai xua. Nguai ta SU dvng chung m9t each c6 y thuc ho~c vo thuc. M9t trong nhfrng bu6c d§.u tien la sv hiSu biSt cua chung ta vs vi~c ung dvng ky thu~t khi nen, c6 nghfa la dung khong khi nen dSn muc c6 th@ chay duqc dS cong tac. M9t nguai Hy l~p ten KTESIBIOS, each day han 2000 nam, da ch@ t~o ra may bin da dAu tien bing khi nen. M9t trong nhung cu6n sach dciu tien da ghi l~i vi~c su dvng khong khi nen nhu m9t ngu6n nang luqng vao ngay dciu tien cua cong nguyen. N6 da mo ta lc;ti cac b9 ph~n diSu khiSn bing khong khi n6ng. Tu "Pneuma" la tu c6 Hy lc;tp c6 nghfa la gi6, la hai tho va trong TriSt h9c n6 c6 nghfa la linh h6n. "Pneumatic" la m9t trong nhung each mieu ta tu "Pneuma". D6 la nganh khoa h9c vS khi d9ng Ive h9c va cac hi~n tuqng lien quan da duqc due kSt. sv hiSu biSt cua nhan loc;ti vs khoa hQC khi nen tu nhung th@ ky d§.u, song phai cha dSn th@ ky nay m6i duqc chung ta nghien cuu c6 h~ th6ng. Tu khi d6 ky thu~t khi nen da thvc sv di vao cac nganh cong nghi~p. DiSu dang quan tam la khong khi nen duqc ap dvng r9ng rai trong cac llnh vvc quan tr9ng, vi dv nhu trong cong nghi~p khai thac qu~ng mo, duong sit, d~t, cong nghi~p thvc phim, ... M~c du ban dciu c6 nhiSu thiSu sot nhung sv b6 sung thuong xuyen nhung tri thuc, kinh nghi~m thvc tS nen sv ap dvng ky thu~t khi nen duqc phat triSn ngay cang mc;tnh han. Ngay nay khong khi nen duqc dung r9ng rai trong cac nha may hi~n dc;ti, duqc b6 tri thanh h~ th6ng ngu6n cung c~p nhu h~ th6ng di~n. II. NHfrNG DaC TRUNG CiiA KHONG KHi NEN C6 thS nguai t~ se ngc;tc nhien vs nhung tiSn b9 vuqt b~c trong li'nh V\fC khi nen v6i m9t thai gian qua ngin.
  6. 5 DiSu nay c6 thS tv hiSu nhu m9t sv k:i~n ma ta k:hong thS khong nh?n biSt r~ng khong m9t each nao don gian hon va hgp ly hon dS giai quySt nhfmg v§n dS ca khi h6a va tv d9ng h6a. Cac d~c trung ca ban cua khong khi nen la: • v~ s6 hrgng: khong kW c6 sin a khiip nai nen c6 thS nen v6i s6 luqng VO he;1n • v~ vin chuy~n: khong khi nen c6 thS V?n chuySn trong cac duong 6ng, v6i m9t k:hoang each nh~t dinh. Cac duong 6ng dftn vS thi khong dn thiSt vi khi se duqc cho thoat ra ngoai moi truong sau khi da cong tac. • v~ hru trfr: may nen khi khong nh~t thiSt phai hoe;1t d9ng lien t1_lC. Khi nen c6 thS duqc luu trfr trong cac binh chua, duqc liip n6i trong cac h~ th6ng 6ng d~n dS cung cfip cho su d1.1ng khi cAn thiSt. • V~ nhi~t dq: khong khi nen it thay d6i theo nhi~t d9. • V~ ch6ng chay n6: khong m9t nguy ca nao gay chay bai khi nen, nen khong t6n chi phi phong chay. Hoe;1t d9ng v6i ap sufit khoang 6 bar nen phong nb khong qua phuc te;1p. • V~ tinh s~ch se: khi nen thi trong se;1ch, ngay ca trong truong hgp la dong chay trong cac duong 6ng hay la trong cac thiSt bi, khong m9t nguy ca gay bAn nao duqc quan tam dSn. Tinh chfit nay rfit cAn thiSt trong cac nganh cong nghi~p chuyen bi~t nhu cong nghi~p thvc phAm, vai sqi, lam san va thu9c da. • v~ ciu t~o cac trang thi~t bj: don gian nen re tiSn • V~ vin t6c: khong khi nen la m9t dong chay c6 luu t6c 16n, cho phep de;1t duqc t6c d9 cao (v?n t6c lam vi~c cac xy lanh thuong tu 1-2m/s, ca bi?t c6 thS de;1t dSn 5 mis). • v~ tinh di~u chinh: V?n t6c va Ive cua nhfmg thiSt bi cong tac b~ng khi nen duqc diSu chinh m9t each vo cfip. • v~ S\f qua tai: cac cong C\l va cac thiSt bi khi nen dam nh?n tai tr9ng cho dSn khi chung dung hoan toan, cho nen se k:hong xay ra qua tai. I)S phan dinh m9t each c~n ke cac li'nh V\fC ap d1.1ng ky thu?t khi nen, cAn phai biSt dSn cac tinh chfit khong thS khong chu tr9ng dSn nhu: • Cach xii: ly: k:hong khi nen phai duqc chuAn bi sao cho khong chua b1.1i bAn, te;1p ch~t hay nu6c, vi chung se gay mon cho cac phAn tu khi nen. • Tinh
  7. 6 III. oic TiNH CUA KHi NEN Khong khi chung quanh ta c6 ap su:it thay d6i, n6 ph\l thu9c vao: • f>Q cao so v6i ID\fC nu6c biSn • Vi tri dia ly • Khi tuQTig Chung ta c6 thS phan lo~i cac lo~i ap su:it sau: A.p suit khi trCYi: la ap su:lt khong khi chung quanh ta. Ap su:lt nay b~ng 1013mbar 6 m\fc nu6c biSn, o0 va 6 vituySn 45° A.p suit chan khong: NSu khi quySn biSn m:it chung quanh qua d§.t, ap su:it khong con nua, ta c6 chan khong tuy~t d6i. Ap su:it duqc biSu di@n so v6i chan khong tuy~t d6i g9i la Ap su:it tuy~t d6i. A.p suit du: la ap suit d9c duqc so v6i ap suit khi quySn Khong khi dung trong cong nghi~p luc d~u la khong khi 6 ap suit khi trai, duqc tang len m9t ap suit cao g9i la Ap su:11 tuang d6i hay con g9i la Ap su:it du (ap suit do) Ansudt An sudt khi An sudtchan A.p sudt chan kh6ng l . IV. CA.CDAILUONG . VAT . LY BS m~t dia c~u duqc bao quanh b6i m9t 16p khong khi. Day la m9t h6n hqp cac khi ck thiSt cho S\f s6ng, c6 ty 1~ tuang ung nhu sau: • Nita chi@m 78% thS tich • Oxy chSm 21 % thS tich • Con l~i la m9t s6 khi khac nhu: carbonic, argon, hydro, neon, heli, cryton, vaxenon f)S hiSu ro them cac dinh lu~t vs d9ng l\fC h9c va tr~ng thai cua khong khi, nguai ta da li?t ke ra sau day cac thong s6 v@ v~t ly va cung v6i cac h~ th6ng do luang. f)S thu~n lqi trong vi~c nghien Clfll va ung d\lllg, nguai ta thuang dung hai h~ th6ng do: h~ th6ng do "Ky thu~t" va h~ th6ng do "SI". Cac thong sB CO' ban
  8. 7 Thong s8 Ky hi~u H~ ky thu~t H~SI Chieu dai 1 Met (m) Met (m) Kh6i luqng m Kp.s 2/m Kg Thai gian t Giay (s) Giay (s) Nhi~t d() T uc UK Cuang d() dong I Ampere (A) A di~n Cuang d() anh Cd Cadela sang , - xuat Cac thong so dan Thong s8 Ky hi~u H~ kv thu~t He SI Lvc F Kp=kg.f= IN= 1 9,8N kg.m/s2 Di~n tfch A m2 m2 ThS tfch V m3 m3 Luuluqng Q m 3/s m3/s Ap suit p at Pa ( ky thu~t) 1 Pa= 1 N/m2 kp/cm2 Bar , 1 Bar= 105 Pa ' Kit h(JJJ giua hf thong tlo lucmg ky thuq,t va quoc te ta c6 cong thuc Newton F=m.a trong d6: m - khf>t luqng a - gia toe g- gia t6c tn,mg truang ( g = 9,81 m/s2) Giua cac cong thuc tren t6n tc;d m6i quan hf sau: Kh8i lu(fng 1 (kg)= 1 kp.s 2/ 9,81.m L{l'c l (kp) = 9,81 (N) DS don gian cho tinh toan ta liy 1 (kp) = 10 (N) Nhift iii) 0 diSm 0: o0c = 273 K (Kelvin) d nhi~t d9 khac: 1°c = 1 K (Kelvin) Ap suat * Atmosphere, [at]: 1 at= 1 kp/cm2 = 0,981 bar * Pascal, Pa ; bar: 1 Pa= 1N/m2 = 10-5 bar va 1 bar= 10-5 N/m2 = 105 Pa= 1 02 at * Atmosphere v~t ly, atm: 1 atm = 1,033 at= 1,013 bar * Milimet c9t nu6c, mm c()t nu6c: 1000 mm c9t nu6c =lat= 0,981 bar *Milimet thuy ngan, mmHg: 1 mmHg = 1 Torr, lat = 736 Torr, 1 bar = 750 Torr JJjnh lu{l,t Boyle - Mariotte
  9. 8 d nhi~t d9 c6 dµih, tich s6 thS tich va ap su&t tuy~t d6i cua m9t khi ly tuong la h~ng s6. Ptuy~t ctbi x V = constant 8bar 4bar 2bar lbar ~H---11- - - ~ Bjnh lu~t Gay-Lussac 6 m
  10. 9 V [cm3] : thS tich khi nen m [kg] = V . r : kh6i luQTig, r la kh6i luQTig rieng cu.a khong khi tinh bkg kg/m3 R [J/kg.K] : h~ng s6 khi . nh""t 1~ d" T [K] 9 tinh b~ang K evm 1. Ap su~t Pa bar mbar at mmWs Torr psi atm Kp/cm2 Kp/cm2 MmH 1 Pa 1 1,000.1 1,000.U 1,02.10- 0,102 7,50.1( 1,45.10- 0,987.1 1 N/m2 o-s 2 5 3 4 o-s 1 bar 1,000.1( 1 1,000.U 1,02 1,02.10~ 0,75.1( 1,45.10 0,987 5 3 3 1 mbar 1,000.1( 1,000.1 1 1,02.10- 1,02.10 0,75 1,45.10- 0,987.1 2 o-3 . 3 2 o-3 2 1 at 0,981.1( 0,981 9,81.10 1 1,000.U 7,36.lC 1,42.10- 0,987 5 4 2 2 1 kp/cm2 lmmW 9,81 0,981.1 9,81.10- 1,000.1 1 7,36.lC 1,42.10- 9,68.10- s o-4 2 o-4 2 3 5 1 kp/m2 lmmH 1,33.102 1,33.10 1 33 1,36.10- 1,36.10 1 1,934.1 1,32.10- g 3 ' 3 o-2 3 1 Torr 1 psi 6,895.1( 6,895.1 6,895.1 7,033.1 7,033.11 5,171.] 1 6,805.1 3 o-2 o-2 2 o-2 0 0 2 1 atm 1,013.1( 1,013 1,013.U 1,033 1,033.11 7,6.10 1,469.1 1 5 3 4 o-2 N dyn kp Mp p 5 4 1 10 0,102 1,02.10- 102 10-5 1 1,02.10- 6 1,02.10- 9 1,02.10-3 9,81 9,81.10 5 1 10-3 103 9,81.10 3 9,81.10 8 103 1 106 9,81.10-3 981 10-3 10-6 1 Dan vi cu.a cong la Joule (J). 1 Joule (J) la cong sinh ra du&i tac d(mg cu.a lvc 1 N dS v~tdich chuySn quangrciuimg lm. ~ .m 2k:~ j erg kpm l
  11. 10 I 1,6.10-19 I l,6.10- 12 \ 1,63.10-20 \ 4,45.10-26 \ 3,83.10-23 \ 1 I Don vi cua cong suit la Watt (W). 1 Watt (W) la cong suit trong thai gian 1 s, sinh ranang Iugng 1 J 1 W - 1 Nm/s w kw Kpm/s PS Kcal/s Kcal/h 3 3 4 1 10- 0,102 1,36.10- 2,39.10- 0,86 3 10 1 102 1,36 0,239 860 3 2 4 9,81 9,81.10- 1 1,33.10- 23,45.10- 8,43 735,5 0,7355 75 1 0,1757 622 4187 4,19 427 5,69 1 3600 3 3 4 1,16 ., 1,16.10- 0,119 1,58.10- , , 2,78.10- 1 ¥ ? V. KHA NANG UNG DVNG CUA KIii NEN 1. Trong Iinh V\fC di~u khi~n H~·th6ng diSu khiSn bfulg khi nen duqc SU d1=1ng (J nhfrng IInh vvc c6 kha nang nguy hiSm nhiSu nhit nhu: chay, n6 ... , vi dv nhu cac thiSt bi phun son, cac 10
  12. 11 2. Nhrrqc di~m • Lvc truySn tai tr9ng nho • Khi tai tr9ng trong h~ th6ng thay d6i, thi v~n t6c truySn cfing thay d6i, vi kha nang dan hf>i cua khi nen 16n, do d6 khong th@ thvc hi~n duqc nhung chuy@n d(mg thilng ho~c quay dSu. • Khi thoat ra gay ra tiSng f>n Do d6 hi~n nay, trong li'nh vvc diSu khi@n nguai ta thuang kSt hqp h~ th6ng diSu khi@n bfulg khi nen v6i CO' khi, ho~c khi nen v6i di~n, di~n tu. Do v~y dt kh6 xac dpih m9t each chinh xac uu khuySt di@m cua tung h~ th6ng diSu khi@n. vn. cAc Lo4-1 MAY KHi NEN vA THIET BJ xuLv KHi NEN 1. May nen khi: a. May nen ki@u Piston (Hinh 2.2): - M()t cfip: ap su§.t xfip xi 600kPa= 6 bar - Hai d.p: ap su§.t x§.p xi 1500kPa- 15bar. C6 thS thiSt kS dSn 4 cfip, P 250bar Luu luqng xfip xi 1Om3/min. Lam vi~c theo nguyen ly thay a6i thi tich piston compressor Refrigeration H1nh 2.2 b. May nen kiSu canh g~t (Hinh 2.3): - M(>t cfip: ap sufit xip xi 400kPa 4bar - Hai cfip: ap su§.t x§.p xi 800kPa = 8bar Lam vi~c theo nguyen ly thay a6i thi tich Luu luqng thS tich Qv ty 1~ thu~n v6i: ·Buang kinh stator, s6 canh va d9 r()ng canh g~t, Sliding vane compressor d9 l~ch tam va t6c d9 quay rotor. c. May nen khi ki@u trvc vit (Hinh 2.4): Lam vi~c theo nguyen ly thay a6i thi tich Ap sufit 16n, xfip xi 1Obar Luu luqng ty 1~ thu~n v6i t6c d9 quay, chiSu dai tfl_lC vit. :~ ' d. May nen khi ki@u ly tam (Hinh 2.5): Lam vi~c theo nguyen ly a
  13. 12 Ap su§.t kha 16n, x§.p xi 1OOOkPa 1Obar Luu lugng ty l? v6i t6c d9 quay, s6 canh va di?n tichcanh. e. May nen khi kiSu hu6ng tf\lC (Hinh 2.6): Lam vi?c theo nguyen ly dong nang Ap su§.t x§.p xi 600kPa~6bar Luu lm;rpg cfing tf l? v6i t6c d9 quay, du~h 2.6 kinh buong hut, so canh va di?n tich canh t 2. ThiJt bj xii' ly khi nen Cac giai do~n XU ly khi nen: - LQC tho: lam mat SO' b9 dS tach ch§.t bfui, bµi; tiSp 11:-- . -- ---~- --c,---o - .... dS tach hoi nu6c. Axial compressor - S§.y kho: Qua trinh v~t ly hay qua trinh hoa h9c. - LQC tinh: Dung b9 l9c va C\}m bao duong (DiSu hoa, ph\lC V\l ) 1. B9 l9c va s§.y kho khi nen (Hinh 2.7) 1111 Khf nen ter may nen khf t -I c=l Khf nen n6ng S.;lCh s~ kh6 c::J Chat lam l,;lnh long ~ Chat lam l.;lnh d.;lng khf 0() ~m. d~u l§n, b1,,1i 1-Hnh ? 7 Nguyen ly ho~t d9ng cua phuang phap s§.y kho bfug ch§.t lam l~nh: khi nen tu may nen khi se qua b9 ph~n trao d6i nhi?t khi-khi (1 ). T~i day dong khi nen vao dang n6ng se dugc lam l~nh nha trao d6i nhi?t v6i dong khi di ra da dugc s§.y kho va lam l~nh. Nhu v~y, t~i khau nay : khi nen vao dugc lam mat, khi nen di ra dugc suoi §.m. Sau khi dugc lam l~nh SO' b9, dong khi nen tiSp t\}C di vao b9 trao d6i nhi~t khi-ch§.t lam l~nh(2). T~i day, dong khi nen dugc lam l~nh dSn nhi?t d9 h6a suang ( khoang +2°C), cac gi9t suang ( mang theo dftu l~n va b\li) se ngung l~i trong thiSt bi (3). Van xa (4) dung dS xa nu6c, dftu l~n va b\li. Cac thiSt bi: (5, 6, 7, 8) dung dS t~o ch§.t lam l~nh v6i kha nang tv d9ng diSu chinh luu lugng, nhi~t d9 cua ch§.t lam l~nh. (1) B9 trao d6i nhi~t Khi-Khi (2) B9 trao d6i nhi?t Khi-Ch§.t lam l~nh (3) B9 ngung t\}, kSt tua (4) Van xa (5) May nen diSu ch@ ch§.t lam l~nh (6) Binh ngung t\l (7) B9 diSu chinh luu lugng ch§.t lam l~nh
  14. 13 (8) B9 diSu chinh nhi~t d9 ch~t lam l
  15. 14 DiSu ki~n cfin la ap su~t 16i vao luon phai cao hon ap su~t lam vi~c cfin cho CO' ciu chip hanh. Nguyen ly lam vi~c: Khi ap suit P 2 , vi d\l tang len do tai tr9ng cua xilanh, khi nen a day c6 thS ti;r thoat ra ngoai qua m
  16. 15 * Do di~n tich cua hai m~t Piston khac nhau nen Ive tac d9ng tren cftn Piston cung khac nhau. * DiSu khiSn bing van 4/2; 5/2 ho~c 5/3 Hinh 2.12 Kv hieu c. Xilanh tac dgng kep c6 d~m giam ch&n (Hinh Dou ble-atting .:yHnde r 2.13) Advance J I+ ... + 0ieu khien tn,1c tiep xilanh Hinh 2.13 tac dung kep b~ng nut an 5/2 d. Xilanh quay DiSu khiSn bing van 4/2; 5/2 hay 5/3 Ky hi~u Xi lanh quay Hinh 2.16 Cftn Piston c6 thanh rang truySn d9ng toi banh rang quay, g6c quay
  17. 16 0- 360°, momen khoang 0,5Nm dSn 20Nm a ap su§.t vc%n hanh 6bar, tuy thu9c duong kinh cua Piston. ~ fr e. D(mg CO' khi nen: y- * KiSu canh g?t (Hinh 2.14) Ky hi~u Dong CO' c6 thS quay tron lien u.ic Hinh 2.14 C6 thS dao chi@u quay, 09ng cd khf nen kieu canh gr,1t diSu khiSn bing van 4/2; 5/2 hay 5/3 * KiSu truySn d9ng xoay (Hinh 2.16): ff Ky hi~u DiSu khiSn bing van 4/2; 5/2 hay 5/3. Hinh 2.15 Goe xoay 0-2 7 0° • I I I T I .N Momen: khoang 0,5Nm dSn 20Nm a ap su§.t vc%n hanh 6bar va ph\l thu9c vao kich 2 thu6c cua canh g?t. f. Giac hut: (Hinh 2.17) Mr,1ch khf nen dung giac hut M9t vong lorn bing cao su co thS treo m9t v~t bing sue hut khi nen. Khi co khi nen th6i tu 2 sang 3, mi~ng hut 1 se t?0 chan khong cho giac hut. Hinh 2.17 '·' ', Giac hilt (Sucker) Van hilt chan khong (Vacuum suction nozzle)
  18. 17 CHUONG II: THIET KE, LAP D~T VA V4N HANH H$ THONG KHi NEN Gioi thi~u: Trong chuong nay se cho nguai h9c c6 nhfmg kiSn thuc, ky nang thiSt kS, Hlp d~t va v~n hanh voi khf nen va nhung ung d\lllg trong h~ th6ng tv d9ng h6a, CO' di~n tu t~i nhung nha may khac nhau. Ml}C tieu: Trang bi cho h9c vien nhfmg kiSn thuc chuyen mon va ky nang nghS nhu sau: Ki~n thfrc chuyen mon: thiSt kS, lip d~t, v~n hanh h~ th6ng khf nen theo yeu c~u, nh~n biSt nhfmg lo~i van, co c§u khf nen .... Ky nang ngh~: KiSm tra, thay th@, sua chfra, Nang c§,p - cai tiSn. Phan tfch h~ th6ng di~n va thiSt bi trong tu di~n diSu khiSn. Thai dq lao dqng: T~p trung, cham chi. Cac ky nang cfin thi~t khac: Nh~y ben, sang t~o, nang d()ng. I. cAc LO~I VAN KHi NEN 1. Ky hi~u chung ciia van di~u khi~n dao chi~u (Directional control valve) Quy uoc biSu diSn cac c6ng vao/ra, cac vi trf chuySn tr~ng thai: I Number of ports II Numberofswitchingpositions 2/2-way valve, normally open position 3/2-way valve, normally closed position 3/2-way valve, normally open position 4/2-way valve flow from 1 ➔ 2 and from 4 ➔ 3 5/2-way valve flow from 1 ➔ 2 and from 4 ➔ 5 5/3-way valve, mid-position closed Trong d6, ky hi~u cac c6ng lam vi~c: Part designations Port deslrrnation in accordance with DIN ISO 5599·3 "Fluld Technology- Pneumattts, 5-Way Valves•i Whrking ports • 1 Supptyport •· 2,4 Working ports. • 3,5 Exhaust ports - Quy uoc biSu diSn cac d~ng tfn hi~u diSu khiSn van (Hinh 2.18):
  19. 18 Types of Actuation Manual actuati,o n Mec::hanl:cal ac.tuatlon Rolliu attual£>d "' Ro lier .tt luaf.i:d only in o ne ,d Ir•ettio n -Spring center£
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