Antifreeze cov nyiaj pab
Antifreeze kuj muaj qhov zoo li hauv qab no:
Thawj yog anti-corrosion. Lub cav thiab nws cov cua txias system yog ua los ntawm cov hlau, tooj liab, hlau, txhuas, hlau thiab cov laug. Cov hlau no tuaj rau hauv cov dej hauv qhov kub thiab muaj peev xwm tuaj yeem corrode thiab xeb dhau sijhawm. Antifreeze tsis tsuas yog tsis ua kom tawg mus rau lub cav txias txias, tab sis kuj tau tiv thaiv corrosion thiab xyaw ua haujlwm.
Qhov thib ob yog high boiling point ntawm lub antifreeze. Lub khob kub npau npau yog 100 ° C, thiab lub npau npau npau npau yog qhov siab tshaj 110 ° C saum toj noj yog tias lub caij ntuj sov, antifreeze coolant yog qhov yooj yim dua qhib dej.
Qhov thib peb yog qhov antifreeze tuaj yeem tiv thaiv kom tsis txhob muaj qhov ntsuas. Dej yog qhov dej txias. Feem ntau tus mob taub hau rau tus tsav tsheb yog qhov teeb meem teev. Cov nplaum adheres mus rau qhov chaw hlau ntawm lub tank dej thiab lub tsho dej, uas ua rau lub cua sov dissipation nyhav zuj zus thiab zuj zus, thiab nws yog qhov nyuaj tshem tawm. Qhov zoo tshaj plaws antifreeze yog ua los ntawm cov dej uas tau muab pov tseg thiab ntxiv nrog cov tshuaj tiv thaiv kev tiv thaiv. Nws tsis tsuas yog tsis muaj nplua, tiam sis tseem muaj nuj nqi. Qhov tseeb, yog tias koj lub tank yog tuab heev, nws yog qhov zoo tshaj plaws los ntxuav nws kom huv nrog lub khob haus tshuaj ua ntej yuav ntxiv tshuaj tiv thaiv.
Ib qho uas tsis tshua khov rau qhov txias txias formulated nrog ib qho tshuaj ntsuab ntxiv rau cov dej txias ntawm lub cav dej txias. Thaum lub ntsuas kub qis tshaj 0 ° C, kev siv cov tshuaj tiv thaiv antifreeze tuaj yeem tiv thaiv kom tsis muaj dej txias tsis zoo thiab cov khoom ntim ntawm cov dej txias, thiab nws tseem txuag tau dej tom qab lub tsheb tawm thiab dej yog ntxiv ua ntej lub tsheb raug rho tawm.
Cov ntawv yuav tsum ua kom muaj kev tiv thaiv kev ua paug yog: kub taw tes thiab flash point; kev kub loj thiab kev sib txuas; tsawg viscosity ntawm tsawg kub, tsis tshua muaj siab vapor, tsis yooj yim rau ua npuas ncauj; tsis muaj corrosion ntawm hlau qhov chaw nyob rau hauv txias system thiab rubber hoses thiab gaskets Deterioration.
Antifreeze feem ntau muab faib ua peb hom: ethanol-dej hom, glycerin-dej hom thiab ethylene glycol-dej hom. Ethanol muaj ib qhov chaw khov ntawm -114 ° C thiab ib qho cheej ntawm 78.3 ° C. Ethanol yog yooj yim ntes hluav taws thiab yooj yim evaporate. Nws cov ntsiab lus yuav tsum tsis pub tshaj 40% thaum nws tau tsim. Nws yuav tsum tsis txhob siv rau hauv lub cav hluav taws xob cua txias nrog kev ua haujlwm siab. Glycerol (glycerol) muaj ib qhov chaw khov ntawm -17 ° C, lub hau chiv ntawm 290 ° C, thiab ib qho chaw khov ntawm -46.5 ° C tom qab sib tov nrog dej. Thaum cov ntsiab lus ntawm glycerin nyob rau hauv cov dej yog tus loj, lub qis free pointing antifreeze tuaj yeem tau, uas yog uneconomical siv. Cov ntsiab lus khov ntawm ethylene glycol yog -11.5 ° C, lub npau npau yog 197.4 ° C, thiab cov ntsiab lus khov dej tom qab nws cov dej tau qis dua li -68 ° C. Ethylene glycol yog yooj yim corrode hlau. Thaum antifreeze yog formulated, anti-corrosion tus neeg sawv cev yuav tsum ntxiv. Feem ntau, 2.5-3.5 g ntawm disodium hydrogen phosphate thiab 1 g ntawm dextrin yog ntxiv rau ib liter ntawm antifreeze. Tus glycol yog hygroscopic heev thiab lub thawv cia yuav tsum raug muab kaw. Ethylene glycol tsis vau, thiab nws yog siv me me, nws yog siv dav. Ntau tus antifreezes muaj qhov loj thermal expansion thiab tsuas yog muab ntxiv rau 95% ntawm tag nrho cov peev xwm ntawm lub zog txias thaum sau. Thaum muab tshuaj antifreeze, qhov chaw khov dej yuav tsum yog 5 ° C qis tshaj qhov ntsuas kub tsawg tshaj plaws hauv cheeb tsam ntawm kev siv.