Hauv kev lag luam tsim thiab cov cuab yeej txij nkawm, tig rov qab (tseem hu ua phau ntawv tig) yog qhov yooj yim ua haujlwm. Nws cuam tshuam nrog tus kheej lossis nrog cov cuab yeej tig mus tig qhov chaw (xws li lub cev muaj zog thiab cov khoom nqus dej) los xyuas lawv cov xwm txheej lubrication, thiab tej yam ua txhaum. Txawm hais tias tus txheej txheem no feem ntau suav tias yog kev ua ub, nws cuam tshuam rau cov khoom siv kev nyab xeeb, cov nyiaj, thiab kev ua haujlwm tsis tuaj yeem tsis quav ntsej.
Ua ntej, tig yog txhais tau tias kev tiv thaiv kev tiv thaiv kev ua haujlwm tsis ua haujlwm. Tom qab ncua sijhawm ntawm cov cuab yeej siv sijhawm (xws li tom qab kev saib xyuas lossis thaum lub caij ntuj no kaw lub caij nyoog), cov khoom siv, thiab lwm yam khoom siv tuaj yeem txeeb tau vim yog lubrication tsis txaus ntseeg lossis xeb. Los ntawm txhais tes tig tau tuaj yeem ntes tsis pom kev tsis txaus siab thiab nrov nrov ua ntej, tiv thaiv kev yuam kev pib uas tuaj yeem hlawv cov tsav lossis puas tsav tsheb. Piv txwv li, hauv kev lag luam tshuaj, pib lub twj tso kua mis tso tawm yam tsis muaj kev ua kom muaj zog tuaj yeem vim tias muaj kev qaug dab peg vim tias kev ua tsis tiav thiab kua dej xau.
Thib ob, tig pab txhim kho cov khoom siv pib. Tig pub rau cov neeg ua haujlwm kom paub meej tias tsis muaj kev sib txhuam sib txhuam ntawm lub rotor thiab ruaj khov chaw (xws li cov vaj tse nyob nruab nrab ntawm lub rotor thiab cov chaw ruaj khov. Cov kauj ruam no yog qhov tshwj xeeb tshaj rau cov koog loj (xws li chav turbines loj thiab compressors), raws li nws tiv thaiv kev ua haujlwm pib ua los ntawm kev sib dhos. Tsis tas li ntawd, cov cranking ib txwm muaj cov khoom siv roj nplua nyeem, txo cov kev sib txhuam qhuav tawg thaum pib.
Thaum kawg, cranking yog qhov ua kom pom kev ntawm cov qauv kev saib xyuas. Ntau lub tuam txhab tso cov ntaub ntawv rau hauv lawv cov txheej txheem tshuaj xyuas, twv ua ntej kev ua raws li cov ntaub ntawv keeb kwm (xws li kev hloov cov ntaub ntawv keeb kwm (xws li kev hloov cov ntaub ntawv keeb kwm (xws li kev hloov cov ntaub ntawv keeb kwm (xws li kev hloov cov ntaub ntawv keeb kwm (xws li kev hloov cov ntaub ntawv keeb kwm (xws li kev hloov cov ntaub ntawv keeb kwm (xws li kev hloov pauv keeb kwm (xws li kev hloov cov ntaub ntawv keeb kwm (xws li kev hloov cov ntaub ntawv keeb kwm (xws li kev hloov cov ntaub ntawv keeb kwm (xws li kev hloov pauv keeb kwm (xws li kev hloov cov ntaub ntawv keeb kwm (xws li kev hloov cov ntaub ntawv keeb kwm (xws li kev hloov cov ntaub ntawv keeb kwm (xws li kev hloov cov ntaub ntawv keeb kwm (xws li kev hloov cov ntaub ntawv keeb kwm (xws li kev hloov cov ntaub ntawv keeb kwm (xws li kev hloov cov ntaub ntawv keeb kwm (xws li kev hloov cov ntaub ntawv keeb kwm (xws li kev hloov cov ntaub ntawv keeb kwm (xws li kev hloov cov ntaub ntawv keeb kwm (xws li kev hloov cov ntaub ntawv keeb kwm (xws li kev hloov cov ntaub ntawv keeb kwm). Qhov no "saib, nug, thiab mloog cov cuab yeej kev kuaj mob, thaum tsis muaj peev xwm txuas ntxiv thiab txo qis kev pheej hmoo ntawm kev pheej hmoo ntawm kev pheej hmoo ntawm kev pheej hmoo.
Hauv cov ntsiab lus, Cranking nyob deb ntawm cov txheej txheem frivolous; Nws yog ib qho kev coj ua tseem ceeb hauv kev tswj hwm cov cuab yeej uas "pom cov duab loj los ntawm qhov me me." Tsuas yog los ntawm kev ua ntej no cov kauj ruam tseem ceeb tuaj yeem peb tso lub hauv paus ruaj khov rau kev nyab xeeb ntau lawm thiab ua haujlwm tau zoo.