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Ch H thng qut v Root BlowerDuytNgi vitTrang

Nguyn Quang Ngc12

H thng qut1. Tng quan. Qut c s dng rng ri trong lnh vc cng nghip v thng mi. T thng gi nh xng ti vn chuyn nguyn liu, ng dng ni hiQut rt quan trng tr gip qu trnh v sc khe con ngi. Trong cng nghip, qut chim 15% cng sut tiu th in cho ng c in. Trong sn xut, tin cy ca h thng qut l quan trng ti s hot ng n nh ca nh my. V d, nu qut phc v cho mc ch cp nguyn liu th khi h thng qut gp s c th dy chuyn s ngng hot ng ngay lp tc. Trong thng gi cng nghip, s c qut s thng xuyn bt buc qu trnh phi dng (mc d c thi gian dng ng trnh t ). Ngay c trong cc lnh vc cc lnh vc si m v lm mt, qut hot ng l iu kin cn thit duy tr qu trnh sn xut. S c qut s dn ti nng sut v cht lng sn phm b st gim. iu ny c bit ng i vi mt s ng dng sn xut khi m khng kh sch l yu t quyt nh ti gim thiu ph phm ( v d cng nghip p nha v cc chi tit in t). Trong mi trng hp, s hot ng ca qut c tc ng ng k n hot ng sn xut ca nh my. V s quan trng ca qut nn cc nh thit k thng c xu hng b p cho s khng chc chn bng cch tng thm cng sut cho qut. Nhng vic qut qu cng sut s tng chi ph vn hnh trong khi li lm gim tin cy ca qut. Qut qu d cng sut so vi s yu cu ca thit b s khng hot ng c im ti u. Cng ging nh h thng bm, qut qu cng sut s lm tng dng nng lng trong lu cht dn n dng lu cht gy n o, lm tng ng sut trn cc thit b trong h thng, chi ph u t ban u cng cao hn2. Cc thnh phn ca h thng qut. Mt h thng qut thng thng bao gm mt qut, mt ng c in, h thng iu khin ng c, ng dn kh, thit b kim sot dng kh v thit b iu ha khng kh ( b lc, b lm mt, b trao i nhit). Tuy nhin, ty thuc vo mc ch s dng thc t v yu cu cng ngh m mt vi thit b c th khng c lp t.

Van u voB lcQut ly tmDy aiM tB iu khin ng cMng ngnTrao i nhitng kh ra.2.1 H thng truyn ng: H thng truyn ng cho php tit kim nng lng v gim chi ph ton h thng. C 2 loi truyn ng c bn l trc tip v truyn ng qua dy ai. Hp gim tc cng c s dng nhng t ph bin. Truyn ng trc tip th qut c ni trc tip vi trc ca ng c, kiu ny n gin nhng km linh hot trong vic thay i tc . Tuy nhin, nh s dng bin tn th c th iu khin c tc d dng. Truyn ng qua ai l loi ph bin nht (ai c nhiu loi nh ai hnh thang, ai rng). S dng truyn ng bng ai c th iu chnh c tc qut, chng xc, bo v h thng. nh my xi mng Nghi Sn, tr qut thi Root Blower dng truyn ng bng dy ai, cc qut cn li u s dng khp ni c kh ( truyn ng trc tip).2.2 Mng v ng dn: i vi hu ht h thng qut, khng kh c truyn dn bi mng hoc ng dn. Mng dng ch yu cho h thng qut c p lc nh trong khi ng dng cho qut c p lc ln2.3 Thit b iu khin lung khng kh: Bao gm cc l chn trong hp, van u vo, u raTy thuc loi qut v yu cu s dng, van iu khin lung khng kh c th c lp u vo, u ra hoc c hai u ca qut.2.4 Thit b s dng u cui ( b trao i nhit, iu ha khng kh) Gip cho iu chnh lung kh t c tnh cht nht nh, v d v m ,nhit Tuy nhin Nghi Sn chng ta khng s dng qut c b phn ny.2.5 Qut C 2 loi qut chnh l: Ly tm v hng trc. Cc loi qut ny khc nhau v hng lung kh qua qut. Qut ly tm s dng cc cnh quay tng tc dng kh. Khi kh di chuyn t trc ca cnh qut ra u cnh qut n s tng thm ng lng. ng lng ny s chuyn thnh p sut tnh v s tng ln ngay trc khi i vo ng x. Qut ly tm thng dng trong cc trng hp lin quan n p lc cao. Chng cng thng c s dng trong trng hp dng kh bn ( m cao v bi), vn chuyn nguyn liu v trong h thng nhit cao. Qut hng trc, nh tn ca n, di chuyn dng kh dc theo trc ca qut. Khng kh c tng p lc bng s gia tng kh ng lc t cc cnh qut, ging nh chn vt v cnh qut my bay. Mc d i khi c th s dng thay th qut ly tm, qut hng trc thng c s dng trong cc qu trnh lm sch khng kh, p sut thp, lu lng ln. Qut hng trc c khi lng phn quay nh hn v kch thc gn hn so vi qut ly tm cng cng sut. Ngoi ra, qut hng trc c xu hng tc cao hn v n hn so vi qut ly tm cng cng sut. Tuy nhin ting n ny bi chi phi bi tn s cao nn d x l.2.5.1 Qut ly tm: a. Qut ly tm c cu to cnh cong v pha trc.Loi qut ny cnh cong theo chiu quay ca qut. ng dng vi trng hp lu lng kh thp v trung bnh. Lm vic p sut thp. u im: t n, kch thc nh.

Nhc im: i hi khng kh sch, kh iu khin chnh xc lng kh u ra. b. Qut ly tm cnh hng tm. Qut ny thng dng i hi lu lng kh thp hoc trung bnh. p sut kh lnu im: Gim bt liu bm dinh vo cnh. V vy cho php vn chuyn dng kh nhiu ht, biQut khe, d thit k.Nhc im: n cao, yu cu chnh xc cao trong thit k v ch to.c. Qut ly tm u cnh hng tm. d. Qut ly tm cnh nghing pha sau. 2.5.2 Qut hng trca. Cnh chn vt b. ng dc trc c. Cnh chong chng. 3. Mi quan h c bn ca qut - nh lut v qut.V2 = V1 () P2 = P1 ()Power2 =Power1 ()Trong : S2, S1 l tc qut.V2, V1 l lu lng kh qua qut ng vi tc S2, S1 tng ng.P2, P1 l p sut kh do qut to ra tc S2, S1 tng ng.Power2, Power1 l cng sut tiu th in ca qut tc S2, S1 tng ng.4. iu khin qut trong trng hp ti thay i thng xuyn.Qut thng xuyn hot ng trong tnh trng ti phm vi rng, lm c iu ny c th iu chnh van u vo, ra ca qut, thay i tc qutGin di y m t mi quan h gia tiu tn in nng v cc phng php c la chn. 5. Nhng nhc im ca h thng qut qu cng sut. Qut qu cng sut gy ra nhiu vn v vn hnh v chi ph hot ng, bao gm: Chi ph u t ln: Qut cng sut ln hn s t tin hn, i hi s dng m t cng ln hn, h qu l h thng qut qu cng sut tng chi ph u t ban u hn. Chi ph nng lng cao: Qut qu cng sut tng chi ph c hai vn chnh l nng lng v sa cha. Chi ph nng lng cao l nguyn nhn ca hai vn c bn: Qut hot ng km hiu qu bi v hiu sut thp, hoc nu qut hot ng vi hiu sut gn ti u th qut qu cng sut s cung cp lung kh nhiu nng lng hn so vi nhu cu, lm tng p lc ln h thng, dn n h thng nhanh b mn v h hi. Hiu qu thp: Qut hot ng qu cng sut thng bu hin cc triu chng nh n, khng hiu qu, khng n nh. Dng kh gy n l kt qu ca dng kh nhiu nng lng hn nhu cu,dn n hng cc kt cu ng v h thng ng dnThng xuyn phi bo tr: Khi h thng qut b qu cng sut th lc tc ng ln bi, h thng truyn ng nhiu hn. Kt qu l phi bo tr nhiu hn. n v rung cao: Qut hot ng km hiu qu lm cho n v rung cao hn. Khi kt cu b rung s lm tng xu hng tch cc phn ca thit b ra. Mt khc n cao cng nh hng xu ti sc khe v nng sut ngi lao ng.

Root Blower.1. Cu to Root blower. Da trn iu kin lm vic c th c cc dng Root blower khc nhau. V c bn Root blower gm c: B phn to chuyn ng: C th l m t in, ng c t trong hoc m t thy lc. B phn dn ng: C th dng khp ni mm, dy ai hoc b gim tc ni trc tip gia lc nn v ng c. B phn thi kh- Blower: Bn trong c nhiu dng cu to khc nhau. B phn chng n: Thng gn lin c b lc kh, gip gim n khi thit b hot ng. Cc thit b ph tr : Bao gm van an ton, cc ng h p sut

6432521 1- Lc nn; 2- M t in; 3- Dy ai v bao che ; 4 B lc kim gim n; 5- Van an ton ; 6- ng h p lc kh u ra.

2. Nguyn tc hot ng Phm vi ng dng.2.1. Nguyn tc hot ng.

Thnh phn chnh ca Root blower l 2 bnh cng tc hnh s tm ( cng c th tham kho dng r to hoc dng cam, vu ). Nhng bnh cng tc ny quay ngc chiu nhau, cng tc , 2 bnh cng tc ny c ni vi mt b bnh rng ng b . Khi chng quay, mt lng kh c nh pha u vo b mc kt gia cc cnh qut v v . Cc bnh cng tc s y lng kh b gi pha x cho d di bt k p sut no trong h thng. Chu k c lp li 4 ln vi mi vng quay. i vi Root blower c 3 vu th nguyn tc hot ng cng tng t. 2.2. Phm vi ng dng.Root blower c ng dng nhiu trong cng nghip nh vn chuyn kh ng hc cc ht liu rn mn ( thc phm, xi mng, ha cht), x l nc thi, ng dng chn khng, qu trnh to sng, nui c, sy kh bng tiRoot blower c th to ra p sut -500 mBar ti 1000 mBar ( -0.5 kgf/cm2 1 kgf/cm2) ty thuc iu kin hot ng.Trong nh my xi mng, c th l nh my xi mng Nghi Sn, cc qut thi Root Blower c dng cho cc h thng rt bt mn t y xi l, kt liu mn hoc vn chuyn than mn.63. Vn hnh Root Blower.3.1 Chun b trc khi chy th.(1).Quay blower bng tay kim tra s chuyn ng t do. Trong trng hp kh quay cn kim tra blower b bin dng do ngoi lctho thit b kim tra bn trong xem c d vt trong bung kh.(2). Kim tra mc du bi trn theo s tay ch dn.(3). Kim tra chnh xc chiu v v tr lp t ca cc thit b ph tr.(4). M van u vo v u ra ca blower. Khng c chy blower khi van ng. c bit ch kim tra bch m ca u vo/ ra c loi b cha?3.2 Chy th Root blower. Khi chy th, m bo rng p sut u vo / ra phi tng thch vi p sut ghi ch trn v thit b.. Nu p sut lm vic thay i, cn phi iu chnh ti van an ton v kim tra ti ca m t. Gi nhit u vo trong gii hn an ton, thng thng phi nh hn 50C. Khi chy th cn kim tra cc hng mc sau:(1).Kim tra chiu quay ca Root blower.(2).Kim tra ting ku l t Root blower.(3). rung ca Root blower.(4).Nhit bun v bung nn ( v blower).(5).Hon thnh chy th, ct ngun in v theo di blower quay t do cho n khi dng hn. Sau khi dng, dng tay quay trc blower kim tra xem c quay m i khng. Nu tt c cc im kim tra trn cho kt qu bnh thng th c th chuyn blower sang ch vn hnh bnh thng.3.3 iu chnh lu lng kh. i vi Root blower, vic iu chnh lu kh bng cch iu chnh van u vao hoc ra l khng em li hiu qu nhiu. iu chnh lu lng kh trong phm vi ln th thay i tc quay ca r to l hiu qu v kinh t nht. Mt khc, lng kh d c th c gii phng qua van an ton nu tc quay ca ng c duy tr khng i. Lp t ng ng bypass gia u vo v u ra cng l mt gi php, nhng cn lu rng nhit c th tng bi dng kh tun hon, n c th gy ha cho qu trnh vn hnh bnh thng.3.4 iu chnh van an ton. Root blower c trang b van an ton v c ci t trc cho mt p sut nht nh. Trc khi chy thc s, xc nh li van an ton c chnh tng thch cha m bo m t v blower hot ng an ton. Nu blower lm vic p sut khc vi p sut t trc hoc nu p sut lm vic yu cu thay i th s gii phng p sut cn c iu chnh qua van an ton.Trnh t iu chnh. (1). Tho lp van.(2). Tho ai c nh v.(3). iu chnh theo p sut yu cu. - h p sut, xoay bu lng iu chnh i ln. - tng p sut, xoay bu lng iu chnh i xung.(4). Th nu nh van an ton x gi tr p sut t trc.(5). Xit cht c nh v.(6). Xit cht np van.(7). Th li xc nh van x p sut ci t.

1- V bc van; 2- Mt ta van; 3- Thn van; 4- Mt ta l xo; 5- L xo; 6- Bu lng iu chnh; 7- c nh v.

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