Mawu Oyamba
M'mafakitale ambiri, mapampu a centrifugal amagwiritsidwa ntchito kunyamula viscous fluid.Pachifukwa ichi, nthawi zambiri timakumana ndi mavuto otsatirawa: kuchuluka kwa viscosity yomwe pampu ya centrifugal imatha kuthana nayo;Kodi kukhuthala kocheperako ndi kotani komwe kumayenera kukonzedwa kuti pampu ya centrifugal igwire ntchito.Izi zimaphatikizapo kukula kwa mpope (kuthamanga kwa mpweya), kuthamanga kwapadera (kutsika kwa liwiro lapadera, kutayika kwakukulu kwa disk friction), kugwiritsa ntchito (zofunikira za dongosolo la kukakamiza), chuma, kusamalitsa, ndi zina zotero.
Nkhaniyi ifotokoza mwatsatanetsatane mphamvu ya mamasukidwe akayendedwe pa kachitidwe ka pampu ya centrifugal, kutsimikiza kwa kuwongolera makulidwe a viscosity coefficient, ndi nkhani zomwe zikufunika kusamaliridwa pakugwiritsa ntchito uinjiniya wothandizana ndi miyezo yoyenera komanso luso laukadaulo laukadaulo, kuti mungotchula.
1. Kukhuthala kwakukulu komwe pampu ya centrifugal imatha kugwira
M'maumboni ena akunja, malire a viscosity pazipita zomwe pampu yapakati ingagwire imayikidwa ngati 3000 ~ 3300cSt (centisea, yofanana ndi mm²/s).Pankhaniyi, CE Petersen anali ndi pepala loyambirira laukadaulo (losindikizidwa pamsonkhano wa Pacific Energy Association mu Seputembara 1982) ndikuyika mkangano woti kukhuthala kwakukulu komwe pampu ya centrifugal imatha kuwerengedwa ndi kukula kwa potulutsa. mphuno, monga momwe zasonyezedwera mu Fomula (1):
Vmax=300(D-1)
Kumene, Vm ndi malo ovomerezeka ovomerezeka a kinematic viscosity SSU (Saybolt universal viscosity) ya mpope;D ndi m'mimba mwake wa nozzle mpope outlet (inchi).
Muzochita zaumisiri wothandiza, fomula iyi ingagwiritsidwe ntchito ngati lamulo lachiwonetsero.Guan Xingfan's Modern Pump Theory and Design imanena kuti: nthawi zambiri, pampu ya vane ndi yoyenera kunyamula ndi mamasukidwe akayendedwe ochepera 150cSt, koma papampu zapakati zokhala ndi NPSHR zocheperako kuposa NSHA, zitha kugwiritsidwa ntchito kukhuthala kwa 500 ~ 600cSt;Kukhuthala kukakhala kokulirapo kuposa 650cSt, magwiridwe antchito a pampu yapakati amachepa kwambiri ndipo sizoyenera kugwiritsidwa ntchito.Komabe, chifukwa pampu ya centrifugal imakhala yosalekeza komanso yowonongeka poyerekeza ndi pampu ya volumetric, ndipo safuna valavu yotetezera komanso kayendetsedwe ka kayendetsedwe kake kamakhala kosavuta, ndizofalanso kugwiritsa ntchito mapampu a centrifugal popanga mankhwala kumene mamasukidwe amafikira 1000cSt.The economic application viscosity ya centrifugal pump nthawi zambiri imakhala pafupifupi 500ct, zomwe zimatengera kukula ndi kugwiritsa ntchito mpope.
2. Chikoka cha mamasukidwe akayendedwe pa ntchito centrifugal mpope
Kutaya kwamphamvu, kukangana kwa pompopompo komanso kutayikira kwamkati mkati mwa chopondera ndi kalozera vane/volute yoyenda ndime ya pampu ya centrifugal zimatengera kukhuthala kwamadzi opopa.Choncho, popopera madzi okhala ndi kukhuthala kwakukulu, ntchito yomwe imatsimikiziridwa ndi madzi idzataya mphamvu.Poyerekeza ndi madzi, ndipamwamba kukhuthala kwamadzimadzi, kumayenda kwakukulu ndi kutaya mutu kwa mpope wopatsidwa pa liwiro lopatsidwa.Choncho, malo abwino kwambiri a pompu amapita kumalo otsika, kutuluka ndi mutu zidzachepa, mphamvu yogwiritsira ntchito mphamvu idzawonjezeka, ndipo mphamvuyo idzachepa.Zolemba zambiri zapakhomo ndi zakunja komanso zoyeserera zamaukadaulo zikuwonetsa kuti mamasukidwe akayendedwe amakhala ndi zotsatira zochepa pamutu pamalo otsekera mpope.
3. Kutsimikiza kwa coefficient yokonza viscosity
Pamene mamasukidwe akayendedwe kuposa 20cSt, zotsatira za mamasukidwe akayendedwe pa ntchito mpope ndi zoonekeratu.Chifukwa chake, muzochita zaukadaulo, kukhuthala kukafika ku 20cSt, magwiridwe antchito a pampu ya centrifugal ayenera kukonzedwa.Komabe, kukhuthala kukakhala pamlingo wa 5 ~ 20 cSt, magwiridwe ake ndi mphamvu zofananira zamagalimoto ziyenera kuyang'aniridwa.
Mukapopera viscous sing'anga, ndikofunikira kusintha mawonekedwe ake pakupopa madzi.
Pakali pano, mafomu, ma chart ndi masitepe owongolera omwe amatengera miyezo yapakhomo ndi yakunja (monga GB/Z 32458 [2], ISO/TR 17766 [3], ndi zina zotero) zamadzimadzi a viscous kwenikweni amachokera ku miyezo ya American Hydraulic. Institute.Pamene ntchito ya pampu yotumizira sing'anga imadziwika kuti ndi madzi, American Hydraulic Institute standard ANSI/HI9.6.7-2015 [4] imapereka njira zowongolera mwatsatanetsatane ndi mawerengedwe oyenera.
4. Zochitika pa ntchito yaumisiri
Kuyambira pakukula kwa mapampu a centrifugal, omwe adatsogolera ntchito yopopa apereka mwachidule njira zingapo zosinthira magwiridwe antchito a mapampu a centrifugal kuchokera kumadzi kupita ku viscous media, iliyonse ili ndi zabwino ndi zoyipa:
4.1 AJStepanoff Model
4.2 Njira ya Paciga
4.3 American Hydraulic Institute
4.4 Germany KSB njira
5.Kusamala
5.1 Media yogwiritsidwa ntchito
The kutembenuka tchati ndi chilinganizo mawerengeredwe ntchito kokha homogeneous viscous madzi, amene nthawi zambiri amatchedwa Newtonian madzi (monga mafuta mafuta), koma sanali Newtonian madzi (monga madzi ndi CHIKWANGWANI, kirimu, zamkati, malasha madzi osakaniza madzi, etc. .)
5.2 Kugwiritsa ntchito kuyenda
Kuwerenga sikothandiza.
Pakadali pano, mafomu owongolera ndi ma chart kunyumba ndi kunja ndi chidule cha data ya epirical, yomwe idzakhala yoletsedwa ndi mayeso.Chifukwa chake, muzochita zauinjiniya, chidwi chapadera chiyenera kuperekedwa ku: mitundu yosiyanasiyana yowongolera kapena ma chart akuyenera kugwiritsidwa ntchito pamayendedwe osiyanasiyana.
5.3 Mtundu wa pampu yogwira ntchito
Mafomu osinthidwa ndi ma chart amangogwira ntchito pamapampu a centrifugal okhala ndi mapangidwe amtundu wa hydraulic, otsegula kapena otsekeka, komanso akugwira ntchito pafupi ndi malo abwino kwambiri (osati kumapeto kwenikweni kwa pompopompo).Mapampu opangira zakumwa za viscous kapena heterogeneous sangathe kugwiritsa ntchito ma fomu ndi ma chart awa.
5.4 Kugwiritsa ntchito cavitation chitetezo malire
Pamene kupopera madzi ndi mkulu mamasukidwe akayendedwe, NPSHA ndi NPSH3 amayenera kukhala okwanira cavitation chitetezo malire, amene ali apamwamba kuposa amene anatchula ena mfundo ndi specifications (monga ANSI/HI 9.6.1-2012 [7]).
5.5 Ena
1) Chikoka cha viscosity pakugwira ntchito kwa pampu ya centrifugal ndizovuta kuwerengedwera ndi chilinganizo cholondola kapena kufufuzidwa ndi tchati, ndipo zitha kusinthidwa ndi mapindikidwe omwe amapezeka kuchokera ku mayeso.Chifukwa chake, pakugwiritsa ntchito uinjiniya, posankha zida zoyendetsera (ndi mphamvu), ziyenera kuganizira kusungitsa malire otetezeka.
2) zakumwa ndi mamasukidwe akayendedwe mkulu kutentha firiji, ngati mpope (monga mkulu-kutentha slurry mpope wa chothandizira akulimbana wagawo mu kuyenga) imayamba pa kutentha m'munsi kuposa yachibadwa ntchito kutentha, makina kapangidwe mpope (monga mphamvu ya shaft ya pampu) ndi kusankha kwa galimoto ndi kugwirizana ziyenera kuganizira mphamvu ya torque yomwe imapangidwa ndi kuwonjezeka kwa viscosity.Pa nthawi yomweyo, ziyenera kukumbukiridwa kuti:
① Pofuna kuchepetsa kutayikira (ngozi zomwe zingatheke), pampu ya cantilever yokhala ndi gawo limodzi iyenera kugwiritsidwa ntchito momwe zingathere;
② Chipolopolo cha mpope chizikhala ndi jekete yotsekera kapena chida chowunikira kutentha kuti chiteteze kulimba kwapakatikati pakutseka kwakanthawi kochepa;
③ Ngati nthawi yotseka ndi yayitali, sing'anga mu chipolopolocho imachotsedwa ndikutsukidwa;
④ Pofuna kupewa mpope kukhala wovuta kusokoneza chifukwa cha kulimba kwa viscous sing'anga pa kutentha kwabwinobwino, zomangira pa mpope zimayenera kumasulidwa pang'onopang'ono kutentha kwapakati kusanatsike kutentha kwanthawi zonse (samalani chitetezo cha ogwira ntchito kuti musawotche. ), kotero kuti thupi la mpope ndi chivundikiro cha mpope zitha kupatulidwa pang'onopang'ono.
3) Pampu yokhala ndi liwiro lapamwamba kwambiri idzasankhidwa momwe ingathere kunyamula madzi a viscous, kuti muchepetse mphamvu yamadzi a viscous pakuchita kwake ndikuwongolera magwiridwe antchito a mpope wa viscous.
6. Mapeto
Kukhuthala kwa sing'anga kumakhudza kwambiri magwiridwe antchito a pampu ya centrifugal.Chikoka cha mamasukidwe akayendedwe pa ntchito ya pampu ya centrifugal ndizovuta kuwerengedwa ndi chilinganizo cholondola kapena kufufuzidwa ndi tchati, kotero njira zoyenera ziyenera kusankhidwa kuti ziwongolere ntchito ya mpope.
Pokhapokha pamene mamasukidwe enieni a sing'anga yopopera amadziwika, angasankhidwe molondola kuti apewe mavuto ambiri omwe amapezeka pamalo omwe amayamba chifukwa cha kusiyana kwakukulu pakati pa kukhuthala koperekedwa ndi kukhuthala kwenikweni.
Nthawi yotumiza: Dec-27-2022