O-ring sealyog ib tug raug extrusion foob. Lub compressibility thiab nro ntawm O-ring seem txoj kab uas hla yog cov ntsiab lus tseem ceeb ntawm kev foob tsim, uas yog qhov tseem ceeb rau kev foob kev ua haujlwm thiab kev pabcuam lub neej. Lub O-ring feem ntau yog ntsia rau hauv qhov sib khi zawj kom kaw. Kev sib khi zoo ntawm O-ring feem ntau yog nyob ntawm qhov sib txuam ntawm qhov loj ntawm O-ntiv nplhaib thiab qhov loj ntawm qhov zawj, tsim qhov tsim nyog ntawm compression thiab nro ntawm lub nplhaib sealing. Sealing ntaus ntawv txheej txheem tsim, yog hais tias lub o-ring compressed ntim me me dhau lawm, yuav ua rau|nce ntws; Yuav ua rau kom loj npaum li cas ntawm compression ntawm O nplhaib roj hmab kev ntxhov siab so thiab|up lub xau. Ib yam li ntawd, o-ring stretch ua haujlwm ntau dhau, kuj tuaj yeem ua rau kev laus thiab|up lub xau. Cov qauv ntawm txhua lub teb chaws hauv ntiaj teb muaj kev cai nruj rau qhov no.
Tsim qauv ntawm O-ring foob
1) Compression ratio
Lub compression ratio W feem ntau yog qhia raws li hauv qab no:
W= (do-h)/do feem pua
Qhov twg ua -- Tshooj txoj kab uas hla ntawm O-ring nyob rau hauv lub xeev dawb (mm)
h -- Qhov kev ncua deb ntawm lub hauv qab ntawm O-ring groove thiab qhov chaw kaw, uas yog, qhov siab ntawm seem ntawmO-ringtom qab compression (mm).
Thaum xaiv qhov compression piv ntawm O-ring, peb yam hauv qab no yuav tsum tau xav txog:
a. Yuav tsum muaj qhov chaw sib txuas kom txaus;
b. Kev sib txhuam me me li sai tau;
c Tsis txhob deformation.
Los ntawm cov xwm txheej saum toj no, nws tsis yog qhov nyuaj kom pom tias muaj kev tsis sib haum xeeb ntawm lawv. Loj compression tus nqi tuaj yeem tau txais kev sib cuag loj, tab sis qhov loj heev compression yuav tsis ua rau nce: loj zawv zawg kev sib txhuam thiab deformation. Txawm li cas los xij, yog tias tus nqi compression tsawg dhau lawm, nws yuav yog vim qhov yuam kev ntawm coaxiality ntawm lub sealing groove thiab O-ring yuam kev tsis ua raws li qhov yuav tsum tau ua, thiab qee qhov ntawm compression yuav ploj mus thiab ua rau to. Yog li ntawd, thaum xaiv qhov compression piv ntawm O - lub nplhaib, nws yog ib qho tsim nyog los ntsuas ntau yam. Feem ntau, qhov compression tus nqi ntawm lub foob zoo li qub yog ntau dua li ntawm lub foob foob, tab sis nws tus nqi siab yuav tsum tsawg dua 30 feem pua (txog rau cov ntaub ntawv roj hmab), txwv tsis pub lub compression kev nyuaj siab yog pom tseeb, uas yuav ua rau ntau deformation, tshwj xeeb tshaj yog loj hauv kub kub tej yam kev mob.
Kev xaiv ntawm O-ring sealing compression tus nqi W yuav tsum xav txog cov kev pabcuam, kev foob zoo li qub lossis lub foob tsis zoo; Static foob tuaj yeem muab faib ua radial foob thiab axial foob; Kev tshem tawm ntawm radial foob (los yog cylindrical zoo li qub foob) yog radial clearance, thiab cov to clearance ntawm axial foob (los yog planar static foob) yog axial clearance. Lub axial foob tau muab faib ua lub siab sab hauv thiab sab nraud raws li lub siab nruab nrab ua haujlwm ntawm txoj kab uas hla sab hauv lossis sab nraud ntawm O-ring. Lub siab sab hauv nce qhov nro, thiab lub siab sab nraud txo qhov kev sib zog pib ntawm O-ring. Rau cov ntaub ntawv sib txawv saum toj no ntawm kev foob zoo li qub, kev taw qhia ntawm kev quab yuam ntawm qhov nruab nrab sealing ntawm O-ring yog qhov sib txawv, yog li cov qauv tsim ua ntej kuj txawv. Rau cov ntsaws ruaj ruaj dynamic, nws yog ib qho tsim nyog kom paub qhov txawv ntawm reciprocating los yog rotating motion seals.
1, static foob: cylindrical zoo li qub foob ntaus ntawv thiab reciprocating sealing ntaus ntawv, feem ntau siv W=10 feem pua ~ 15 feem pua ; Flat foob pob
Wb hais tias W yog 15 feem pua rau 30 feem pua.
2. Rau dynamic foob, nws tuaj yeem muab faib ua peb qhov xwm txheej:
a, reciprocating motion foob feem ntau siv W= 10 feem pua ~ 15 feem pua .
b. Joule thermal nyhuv yuav tsum raug coj mus rau hauv tus account thaum xaiv qhov compression tus nqi ntawm cov lus tsa suab foob. Feem ntau hais lus, sab hauv txoj kab uas hla ntawm O-ring rau rotary motion yog 3 feem pua ~ 5 feem pua loj dua lub axial txoj kab uas hla, thiab tus compression tus nqi ntawm lub sab nraud txoj kab uas hla W=3 feem pua ~ 8 feem pua.
C. Kev sib txhuam qis qis nrog O-ring, txhawm rau "txo kev sib txhuam tsis zoo, feem ntau xaiv qhov me me compression tus nqi, uas yog, W= 5 feem pua ~ 8 feem pua. Tsis tas li ntawd, xav txog lub hneev |} huab hwm coj thiab kub ntawm Cov khoom siv roj hmab feem ntau, sab nraud ntawm qhov muab compression deformation, qhov siab tshaj plaws nthuav tawm tau tso cai yog 15 feem pua ntawm qhov ntau tshaj qhov qhia tau hais tias cov khoom tsis haum, thiab O-rings ntawm lwm cov ntaub ntawv yuav tsum tau siv, los yog muab compression deformation tus nqi yuav tsum yog. Kho kom raug tus nqi tshwj xeeb ntawm compression deformation, nyob rau hauv ib txwm muaj xwm txheej, lub teb chaws yog raws li lawv tus kheej kev paub los tsim qauv lossis muab cov lus pom zoo.
2) Tensile muaj peev xwm
O - nplhaib nyob rau hauv lub sealing zawj tom qab thauj khoom, feem ntau muaj qee qhov nro. Tsis zoo li tus nqi compression, tus nqi ntawm qhov nro kuj muaj txiaj ntsig zoo rau kev sib khi ua haujlwm thiab kev pabcuam lub neej ntawm O-ring. Qhov loj tensile tus nqi yuav tsis tsuas yog ua rau lub installation ntawm O-ring teeb meem, tab sis kuj yog vim qhov kev hloov ntawm txoj kab uas hla ntawm seem ua, compression tus nqi yuav raug txo, uas ua rau to. Lub stretching npaum li cas yuav qhia tau raws li nram no:
a=(d plus do)/(d1 plus do)
Hauv cov mis
d -- qag txoj kab uas hla (mm);
d1 -- Sab hauv txoj kab uas hla ntawm O-ring (mm);
ua -- Seem txoj kab uas hla ntawm O-ring (mm).
3) Kev sib cuag dav
Thaum O-ring yog loaded rau hauv lub sealing groove, nws cross-section ua compression deformation. Qhov dav tom qab deformation thiab qhov dav ntawm kev sib cuag nrog cov ncej muaj feem xyuam rau kev ua haujlwm sealing thiab kev pabcuam lub neej ntawm O-ring, tus nqi tsawg dhau yuav ua rau kev sib khi ua haujlwm cuam tshuam; Loj dhau yuav ua rau muaj kev sib txhuam, kev sib txhuam kub, cuam tshuam rau lub neej ntawm O-ring.
Qhov dav BO (mm) tom qab deformation ntawm O-ring muaj feem xyuam rau qhov sib piv W ntawm O-nplhaib thiab seem kab dO, uas tuaj yeem xam los ntawm cov qauv hauv qab no
BO={1/(1-w)-0.6W}dO (W noj 10 feem pua ~ 40 feem pua)
Qhov dav b (mm) ntawm qhov chaw sib cuag ntawm O-ring thiab ncej kuj nyob ntawm W thiab dO:
b{{0}}(4W2 ntxiv 0.34W ntxiv rau 0.31)dO (W=10 feem pua -40%)
Rau O-ring seals nrog kev sib txhuam ntau dua, xws li pneumatic seals thiab hydraulic servo tswj cov ntsaws ruaj ruaj, kev sib txhuam tuaj yeem kwv yees raws li.
