Nyob rau hauv xyoo tas los no, SIL daim ntawv pov thawj tau nce ntxiv nyob rau hauv cov ntaub ntawv kev yuav khoom valve. Cov ntsiab lus hauv qab no hais txog cov ntsiab lus tseem ceeb, qhov ntsuas, thiab txoj hauv kev siv.
1. Dab tsi SIL Measures
SIL (Safety Integrity Level) qhia qhov tshwm sim ntawm qhov ua tsis tiav ntawm qhov kev thov ntawm kev ntsuas kev nyab xeeb. Rau SIL 2, qhov nruab nrab qhov tshwm sim ntawm qhov tsis ua tiav ntawm kev thov (PFDavg) yuav tsum nyob nruab nrab ntawm 10−310−3 thiab 10–210−2.
Kev ntsuam xyuas SIL tsom rau kev ntseeg siab ntawm kev ua haujlwm raws li qhov xav tau, tsis yog ntawm cov khoom siv dav dav. Rau ib lub valve, daim ntawv pov thawj tau txais yog "SIL muaj peev xwm daim ntawv pov thawj," uas cov ntaub ntawv tseem ceeb tsis ua hauj lwm nrog rau λDU (kev phom sij tsis pom zoo tus nqi), λDD (kev phom sij pom qhov tsis ua hauj lwm), thiab SFF (safe tsis ua hauj lwm feem).
2. Core Parameters rau kev ua tiav SIL 2
SFF (Safe Failure Fraction) thiab HFT (Hardware Fault Tolerance):Raws li IEC 61508-2, hardware architectural constraints raug siv ua ke. Rau hom B Cheebtsam (uas suav nrog li qub, actuators, thiab positioners), ib qho channel (HFT=0) yuav tsum muaj SFF nyob rau hauv thaj tsam ntawm 60% mus rau 90% los txhawb SIL 2. Yog tias SFF qis dua 60%, ib qho kev sib txuas ib leeg tsis tso cai rau SIL 2. Thaum siv cov khoom siv rov ua dua tshiab (HFT1 Greater dua) 60-90% ntau yam tuaj yeem txhawb SIL ntau dua.
Diagnostic Coverage:Kev kuaj mob ntau ntxiv, piv txwv li los ntawm Ib Feem Kev Ntsuas Stroke (PST), tuaj yeem hloov qee qhov "tsis pom tau" txaus ntshai ua tsis tiav rau "kuaj" cov. Muab hais tias PST zaus yog tsawg kawg yog kaum npaug ntawm cov pov thawj-test ncua sij hawm, ib leeg-channel hom B yam nrog SFF> 60% tuaj yeem siv rau hauv SIL 2 daim ntawv thov.
3. Txoj Kev Sib Koom Tes
Peb txoj hauv kev tseem ceeb yog siv los ua kom tiav SIL 2 daim ntawv pov thawj:
Txoj Kev A: Redundant Solenoid li qub (1oo2 hauv series)- Ib qho ntxiv solenoid valve ntawm tib tus qauv yog ntsia hauv series nrog rau qhov uas twb muaj lawm. Lub valve tseem qhib yog hais tias lub solenoid yog energized, thiab kaw tsuas yog thaum ob qho tib si de-energised. Qhov kev xaiv no muaj tus nqi pib qis thiab tsim nyog rau kev lees paub thawj zaug, nrog rau lub sijhawm sijhawm ntawm 3 txog 6 lub hlis.
Txoj Kev B: Partial Stroke Test (PST) Module- Ib qho PST module yog ntxiv rau lub positioner lossis actuator, cia li txav lub valve 10% mus rau 20% ntawm nws cov hlab ntsha thiab tom qab ntawd rov qab los, tsis tas yuav kaw tag nrho. Qhov no converts undetected tsis ua hauj lwm rau hauv kev kuaj pom tsis ua hauj lwm. Nws muaj qhov sib npaug ntawm tus nqi-qhov txiaj ntsig thiab feem ntau xav tau 6 txog 12 lub hlis.
Txoj Kev C: Kev Hloov Kho Valve (1oo2 lossis 2oo3)- Ob lossis peb qhov kev ywj pheej thiab cov actuators yog siv, nrog cov khoom siv cua thiab hluav taws xob sib cais, thiab kev sib cais ntawm lub cev. Ib qho kev kaw ib leeg tuaj yeem cais cov txheej txheem. Txoj hauv kev no hais txog cov xwm txheej xav tau kev nyab xeeb dua thiab feem ntau siv sijhawm 12 txog 18 lub hlis.
4. Kev txiav txim siab txog daim ntawv pov thawj
Daim Ntawv Pov Thawj:Cov ntaub ntawv tshaj tawm los ntawm TÜV, exida, BV, SGS, thiab lwm lub koom haum thoob ntiaj teb lees paub feem ntau lees txais los ntawm cov haujlwm loj.
Certificate validity:Daim ntawv pov thawj yuav tsum nyob twj ywm siv tau thoob plaws lub sijhawm tsim ua haujlwm; tas sij hawm tuaj yeem cuam tshuam qhov kev lees txais.
Kev npaj:Muaj cov ntaub ntawv xws li FMEDA cov ntawv ceeb toom, phau ntawv qhia kev nyab xeeb, thiab ISO 9001 kev tswj hwm qhov system cov ntaub ntawv ncaj qha cuam tshuam rau cov ntawv pov thawj ncua sij hawm thiab cov nqi.
5. Cov Lus Nug Txog Kev Sib Tham
Thaum qhov kev sib tw qhia txog SIL 2 tab sis tsis qhia meej txog hom ntawv pov thawj xav tau, SIL daim ntawv ntsuam xyuas muaj peev xwm los ntawm lub cev tau lees paub, suav nrog cov ntaub ntawv tsis ua haujlwm thiab cov txheej txheem suav, yuav tsum tau muab.
Rau SIL 3 daim ntawv thov, ib leeg-channel architecture tsis txaus; yuav tsum muaj 1oo2 lossis 2oo3 redundant tov.
Cov ntsiab lus
SIL daim ntawv pov thawj ua raws li qhov yuav tsum tau ua ua ntej rau kev nkag mus rau kev lag luam hauv ntau cov txheej txheem kev lag luam. Kev xaiv txoj hauv kev tsim nyog thiab kev daws teeb meem raws li cov khoom lag luam thiab cov phiaj xwm xav tau yog ib txoj hauv kev ua tau zoo. Rau cov lus nug tshwj xeeb lossis kev pab xaiv, kev sab laj nrog lub tuam txhab kev cob qhia raug pom zoo.
