I-Cavitation yisimo esiyingozi esivame ukwenzeka kumayunithi okumpompa amaphakathi. I-Cavitation inganciphisa ukusebenza kahle kwepompo, ibangele ukudlidliza nomsindo, futhi iholele ekulimaleni okukhulu kwe-impeller yepompo, izindlu zepompo, i-shaft, nezinye izingxenye zangaphakathi. I-Cavitation yenzeka lapho umfutho we-fluid empompini wehla ngaphansi komfutho we-vaporization, okwenza amabhamuza omhwamu akheke endaweni enomfutho ophansi. Lawa mabhamuza omhwamuko ayagoqa noma "aqhume" ngobudlova lapho engena endaweni enengcindezi ephezulu. Lokhu kungabangela ukulimala komshini ngaphakathi kwephampu, kudale amaphuzu abuthakathaka asengozini yokuguguleka nokugqwala, futhi kuphazamise ukusebenza kwephampu.

Ukuqonda nokusebenzisa amasu okunciphisa i-cavitation kubalulekile ekugcineni ubuqotho bokusebenza kanye nempilo yesevisi ye amaphampu e-casing ehlukanisayo .

Izinhlobo Cavitation in Pumps

Ukunciphisa noma ukuvimbela i-cavitation epompo, kubalulekile ukuqonda izinhlobo ezahlukene ze-cavitation ezingase zenzeke. Lezi zinhlobo zihlanganisa:

1.I-vaporization cavitation. Eyaziwa nangokuthi "i-classic cavitation" noma "i-net positive suction head etholakalayo (NPSHa) cavitation," lolu uhlobo oluvame kakhulu lwe-cavitation. Hlukanisa i-casing amaphampu andisa isivinini soketshezi njengoba ludlula emgodini wokudonsa i-impeller. Ukwenyuka kwesivinini kulingana nokuncipha komfutho wamanzi. Ukwehliswa kwengcindezi kungase kubangele ukuthi olunye uketshezi lubilise (ukuhwamuka) bese kwakheka amabhamuza omhwamuko, azobhidlika ngamandla futhi akhiphe amaza okwethuka amancane lapho efika endaweni enengcindezi ephezulu.

2. I-Trbulent cavitation. Izingxenye ezifana nezindololwane, amavalvu, izihlungi, njll. ohlelweni lwamapayipi kungenzeka zingalifanele inani noma imvelo yoketshezi olumpontshwayo, olungabangela ama-eddies, isiphithiphithi kanye nokwehluka kwengcindezi kulo lonke uketshezi. Uma lezi zenzakalo zenzeka endaweni yokungena yepompo, zingaguguleka ngokuqondile ingaphakathi lepompo noma zenze uketshezi luhwamuke.

3. I-Blade syndrome cavitation. Eyaziwa nangokuthi "i-blade pass syndrome", lolu hlobo lwe-cavitation lwenzeka lapho i-diameter ye-impeller inkulu kakhulu noma i-coating yangaphakathi yendlu yephampu iminyene kakhulu / ububanzi bangaphakathi bepompo buncane kakhulu. Lezi zimo noma zombili lezi zimo zizonciphisa isikhala (ukusula) ngaphakathi kwendlu yephampu sibe ngaphansi kwamazinga amukelekayo. Ukuncipha kokuvunyelwa ngaphakathi kwendlu yepompo kubangela ukuthi izinga lokugeleza kwamanzi likhuphuke, okuholela ekwehleni kokucindezela. Ukunciphisa ingcindezi kungase kubangele uketshezi ukuba luhwamuke, kwakheka amabhamuza e-cavitation.

I-4.Internal recirculation cavitation. Uma iphampu ehlukanisa phakathi nendawo ingakwazi ukukhipha uketshezi ngesilinganiso sokugeleza esidingekayo, ibangela ukuthi olunye noma lonke uketshezi lujikeleze kabusha eduze kwe-impeller. Uketshezi olujikelezayo ludlula ezindaweni ezinomfutho ophansi nophezulu, okukhiqiza ukushisa, isivinini esikhulu, futhi kwakhe amabhamuza okuhwamuka. Isizathu esivamile sokujikeleza kabusha kwangaphakathi ukugijima kwepompo nge-valve yokuphuma kwepompo ivaliwe (noma ngezinga eliphansi lokugeleza).

5. Air entrainment cavitation. Umoya ungadonselwa epompo ngevalvu ehlulekile noma ukufaka okuxekethile. Uma usungaphakathi empompini, umoya uhamba noketshezi. Ukuhamba koketshezi nomoya kungakha amabhamuza "aqhuma" lapho evezwe ekucindezelweni okwandayo kwe-impeller yepompo.

Izinto ezifaka isandla ku-cavitation - NPSH, NPSHa, kanye ne-NPSHr

I-NPSH iyisici esibalulekile ekuvimbeleni i-cavitation kumaphampu we-split casing. I-NPSH umehluko phakathi kwengcindezi yangempela yokumunca kanye nomfutho womhwamuko woketshezi, olinganiswa endaweni yokungena yepompo. Amanani e-NPSH kufanele abe phezulu ukuze kuvinjelwe uketshezi ekuhwameni ngaphakathi kwepompo.

I-NPSha iyi-NPSH yangempela ngaphansi kwezimo zokusebenza zephampu. Kudingeka ikhanda eliphelele lokumunca eliphozithivu (NPSHr) ubuncane be-NPSH obucaciswe umkhiqizi wephampu ukugwema i-cavitation. I-NPSha iwumsebenzi wokudonsa amapayipi, ukufakwa, kanye nemininingwane yokusebenza kwephampu. I-NPSHr iwumsebenzi womklamo wepompo futhi inani layo linqunywa ukuhlolwa kwepompo. I-NPSHr imele ikhanda elitholakalayo ngaphansi kwezimo zokuhlola futhi ngokuvamile ikalwa njengokwehla okungu-3% kwekhanda lepompo (noma isigaba sokuqala se-impeller head for multistage pumps) ukuze kutholwe i-cavitation. I-NPSha kufanele ihlale inkulu kune-NPSHr ukugwema i-cavitation.

Amasu Okunciphisa I-Cavitation - Ukwandisa i-NPSHa Ukuvimbela I-Cavitation

Ukuqinisekisa ukuthi i-NPSHa inkulu kune-NPSHr kubalulekile ekugwemeni i-cavitation. Lokhu kungazuzwa ngokuthi:

1. Ukwehlisa ukuphakama kwephampu ye-casing casing ngokuhlobene ne-suction reservoir/sump. Izinga loketshezi ku-reservoir suction/sump linganyuswa noma iphampu ingafakwa ngaphansi. Lokhu kuzonyusa i-NPSHa endaweni yokungena yepompo.

2. Khulisa ububanzi bepayipi lokudonsa. Lokhu kuzonciphisa isivinini soketshezi ngezinga lokugeleza okungaguquki, ngaleyo ndlela kunciphise ukulahlekelwa kwekhanda lokumunca ekufakweni kwamapayipi nokufakwa.

2.Yehlisa ukulahlekelwa kwekhanda ekufakweni. Yehlisa inani lamalunga emgqeni wokudonsa wepompo. Sebenzisa okokufaka okufana namandololwane erediyasi ende, amavalvu abhorekile agcwele, nezinciphisi ezicijile ukusiza ukwehlisa ukulahleka kwekhanda lokumunca ngenxa yezixhumi.

3.Gwema ukufaka izikrini nezihlungi emugqeni wokudonsa wepompo noma nini lapho kunokwenzeka, njengoba kuvame ukubangela i-cavitation kumaphampu we-centrifugal. Uma lokhu kungenakugwema, qiniseka ukuthi izikrini nezihlungi emugqeni wokudonsa wepompo zihlolwa njalo futhi ziyahlanzwa.

5. Pholisa uketshezi olupompowe ukuze unciphise umfutho wawo womhwamuko.

Qonda i-NPSH Margin ukuze uvimbele i-Cavitation

Imajini ye-NPSH ingumehluko phakathi kwe-NPSHa ne-NPSHr. Umkhawulo omkhulu we-NPSH unciphisa ingozi ye-cavitation ngoba inikeza isici sokuphepha ukuvimbela i-NPSHa ekuweleni ngaphansi kwamazinga okusebenza avamile ngenxa yezimo zokusebenza ezishintshayo. Izinto ezithinta imajini ye-NPSH zihlanganisa izici zoketshezi, isivinini sepompo, nezimo zokumunca.

Ukugcina Ukugeleza Kwephampu Okuncane

Ukuqinisekisa ukuthi iphampu ye-centrifugal isebenza ngaphezu kokugeleza okuncane okucacisiwe kubalulekile ekwehliseni i-cavitation. Ukusebenzisa iphampu yecala elihlukanisiwe ngaphansi kobubanzi bayo bokugeleza obulungile (indawo yokusebenza evumelekile) kwandisa amathuba okudala indawo yokucindezela ephansi engabangela i-cavitation.

Ukucatshangelwa kwe-Impeller Design ukunciphisa i-Cavitation

Ukuklanywa kwe-impeller kudlala indima ebalulekile ekutheni ipompo ye-centrifugal ijwayele yini i-cavitation. Ama-impeller amakhulu anama-blades ambalwa athambekele ekunikezeni ukusheshisa okuncane koketshezi, okunciphisa ingozi ye-cavitation. Ukwengeza, ama-impeller anama-diameter ama-inlet amakhudlwana noma ama-tapered blades asiza ukuphatha ukugeleza koketshezi kahle kakhudlwana, anciphise ukuxokozela nokwakheka kwamabhamuza. Ukusebenzisa izinto ezimelana nokulimala kwe-cavitation kungandisa impilo ye-impeller nepompo.

Ukusebenzisa Amadivayisi e-Anti-Cavitation

Amadivayisi we-Anti-cavitation, njengezesekeli ze-flow conditioning noma ama-cavitation suppression liners, ayasebenza ekunciphiseni i-cavitation. Lawa madivayisi asebenza ngokulawula amandla e-fluid azungeze i-impeller, anikeze ukugeleza okuqinile futhi anciphise i-turbulence nezindawo eziphansi zokucindezela ezibangela i-cavitation.

Ukubaluleka Kokulinganisa Kwephampu Okufanelekile Ekuvimbeleni I-Cavitation

Ukukhetha uhlobo lwepompo olulungile nokucacisa usayizi olungile wohlelo oluthile kubalulekile ekuvimbeleni i-cavitation. Ipompo enkulu ingase ingasebenzi ngokuphumelelayo ekugelezeni okuphansi, okuholela engozini eyengeziwe ye-cavitation, kuyilapho ipompo encane ingase isebenze kanzima ukuze ihlangabezane nezidingo zokugeleza, okwandisa amathuba okuba ne-cavitation. Ukukhetha iphampu ngendlela efanele kuhilela ukuhlaziya okuningiliziwe kwezidingo eziphezulu, ezijwayelekile nezincane zokugeleza, izici zoketshezi kanye nesakhiwo sohlelo ukuze kuqinisekiswe ukuthi iphampu isebenza ngaphakathi kwebanga elishiwo lokusebenza. Ukulinganisa okunembile kuvimbela i-cavitation futhi kwandisa ukusebenza kahle nokuthembeka kwepompo phakathi nomjikelezo wayo wokuphila.