Posankha mapampu amadzi, ngati kusankhako sikuli koyenera, mtengo wake ukhoza kukhala wokwera kapena magwiridwe antchito enieni a pampu sangakwaniritse zosowa za malo ogwirira ntchito. Tsopano perekani chitsanzo kuti muwonetse mfundo zina zomwe pampu yamadzi iyenera kutsatira.
Kusankha pampu yoyamwa kawiri kuyenera kulabadira mfundo zotsatirazi:
1. Liwiro:
Liwiro labwinobwino limatsimikiziridwa malinga ndi zofunikira za kasitomala. Liwiro la pampu yomweyo likachepa, kuchuluka kwa madzi ndi kukweza kwake kudzachepa. Posankha chitsanzo, ndikofunikira kuganizira osati momwe zinthu zilili pazachuma zokha, komanso momwe malo ake alili, monga: kukhuthala kwa sing'anga, kukana kukalamba, mphamvu yodzipangira yokha, zinthu zogwedera, ndi zina zotero.
2. Kutsimikiza kwa NPSH:
NPSH ikhoza kudziwika malinga ndi mtengo womwe waperekedwa ndi kasitomala, kapena malinga ndi momwe pampu imalowera, kutentha kwapakati komanso kuthamanga kwa mpweya pamalopo:
Kuwerengera kutalika kwa pampu yamadzi (njira yosavuta: malinga ndi kuthamanga kwa mpweya ndi kutentha kwabwinobwino kwa madzi) ndi motere:
Pakati pawo: hg—kutalika kwa kukhazikitsa kwa geometric (mtengo wabwino ndi kukwera mmwamba, mtengo woipa ndi kuyenda mobwerera m'mbuyo);
—Mutu wa madzi othamanga mumlengalenga pamalo oyikapo (wowerengedwa ngati 10.33m pansi pa kuthamanga kwa mpweya ndi madzi oyera);
hc—kutayika kwa madzi otulutsa madzi; (ngati payipi yolowera ndi yochepa komanso yosavuta, nthawi zambiri imawerengedwa ngati 0.5m)
—Mutu wa kuthamanga kwa nthunzi; (madzi oyera pa kutentha kwa chipinda amawerengedwa ngati 0.24m)
— NPSH yololedwa; (kuti muwonetsetse kuti ndi yotetezeka, werengerani molingana ndi NPSHr×1.2, NPSHr onani kabukhu)
Mwachitsanzo, NPSH NPSHr=4m: Kenako: hg=10.33-0.5-0.24-(4×1.2)=4.79 m (zotsatira zake ndi zabwino, zikutanthauza kuti zimatha kuyamwa mpaka ≤4.79m, ndiko kuti, mulingo wolowera madzi ukhoza kukhala mu impeller Mkati mwa 4.79m pansi pa mzere wapakati; ngati ili pansi pa kupanikizika koyipa, iyenera kutsanulidwa, ndipo mtengo wothira madzi kumbuyo uyenera kukhala waukulu kuposa mtengo wowerengedwa, ndiko kuti, mulingo wolowera madzi ukhoza kukhala pamwamba pa mtengo wowerengedwa pamwamba pa mzere wapakati wa impeller).
Zomwe zili pamwambapa zimawerengedwa malinga ndi kutentha kwabwinobwino, madzi oyera komanso kutalika kwabwinobwino. Ngati kutentha, kuchulukana ndi kutalika kwa sing'anga sikwabwinobwino, kuti tipewe kutsekeka kwa madzi ndi mavuto ena omwe amakhudza magwiridwe antchito abwinobwino a pampu, mitengo yofanana iyenera kusankhidwa ndikusinthidwa kukhala fomula yowerengera. Pakati pawo, kutentha ndi kuchulukana kwa sing'anga kumawerengedwa malinga ndi mitengo yofanana mu "Kupanikizika ndi Kuchuluka kwa Madzi pa Kutentha Kosiyanasiyana", ndipo kutalika kumawerengedwa malinga ndi mitengo yofanana mu "Kukwera ndi Kupanikizika kwa Mlengalenga kwa Mizinda Ikuluikulu M'dziko". NPSH ina yovomerezeka ndikuwonetsetsa kuti pali chitetezo, malinga ndi NPSHr×1.4 (mtengo uwu ndi osachepera 1.4).
3. Ngati mphamvu yolowera ya pampu yachizolowezi ndi ≤0.2MPa, pamene mphamvu yolowera + mutu × nthawi 1.5 ≤ mphamvu yolowera, sankhani malinga ndi zinthu zachizolowezi;
Kupanikizika kwa malo olowera + mutu × nthawi 1.5 > kupsinjika, zipangizo zomwe zimakwaniritsa zofunikira ziyenera kugwiritsidwa ntchito; ngati kuthamanga kwa malo olowera kuli kokwera kwambiri kapena kuthamanga kwa mayeso kuli kokwera kwambiri, ndi zina zotero zomwe sizikukwaniritsa zofunikira, chonde tsimikizirani ndi ukadaulo wosinthira zinthuzo kapena kukonza nkhungu ndikuwonjezera makulidwe a khoma;
4. Mitundu ya makina osindikizira a pampu wamba ndi awa: M7N, M74 ndi M37G-G92, yomwe mungagwiritse ntchito kutengera kapangidwe ka pampu, zinthu zamakina osindikizira wamba: zolimba/zofewa (tungsten carbide/graphite); pamene mphamvu yolowera ndi ≥0.8MPa, chisindikizo chamakina choyenera chiyenera kusankhidwa;
5. Ndikofunikira kuti kutentha kwapakati kwa pampu yopopera kawiri kusapitirire 120°C. Pamene 100°C ≤ kutentha kwapakati ≤ 120°C, pampu yachizolowezi iyenera kukonzedwa: malo otsekera ndi gawo lonyamulira ziyenera kukhala ndi madzi ozizira kunja kwa malo oziziritsira; mphete zonse za O za pampu zimapangidwa ndi Zonse ziwiri: rabara ya fluorine (kuphatikiza chisindikizo cha makina).
Nthawi yotumizira: Meyi-10-2023