Tijaabada caddayntu waa qayb muhiim ah oo ka mid ah ilaalinta hufnaanta badbaadada ee nidaamyadayada qalabka badbaadada (SIS) iyo nidaamyada la xiriira badbaadada (tusaale ahaan digniinaha muhiimka ah, nidaamyada dabka iyo gaaska, nidaamyada isku xidhka qalabka, iwm.). Tijaabada caddayntu waa tijaabo xilliyeed si loo ogaado cilladaha khatarta ah, tijaabinta shaqada la xiriirta badbaadada (tusaale dib-u-dejinta, marin-u-dhaca, digniinaha, ogaanshaha, xidhitaanka gacanta, iwm.), iyo hubinta in nidaamku uu buuxiyo heerarka shirkadda iyo kuwa dibadda. Natiijooyinka tijaabada caddayntu sidoo kale waa cabbiraadda waxtarka barnaamijka daacadnimada farsamada ee SIS iyo isku hallaynta goobta ee nidaamka.
Nidaamyada tijaabada caddeynta waxay daboolayaan tallaabooyinka imtixaanka laga bilaabo helitaanka ruqsadaha, sameynta ogeysiisyada iyo ka saarista nidaamka adeegga imtixaanka ilaa hubinta tijaabinta dhammaystiran, diiwaangelinta imtixaanka caddeynta iyo natiijooyinkiisa, dib u dhigista nidaamka shaqada, iyo qiimeynta natiijooyinka imtixaanka hadda jira iyo natiijooyinka imtixaanka caddeynta ee hore.
ANSI/ISA/IEC 61511-1, Qodobka 16, wuxuu daboolayaa tijaabada caddaynta SIS. Warbixinta farsamada ISA TR84.00.03 - "Daacadnimada Farsamada ee Nidaamyada Qalabka lagu rakibay (SIS)," waxay daboolaysaa tijaabada caddaynta waxaana hadda dib loo eegayaa iyadoo nooc cusub la filayo inuu dhawaan soo baxo. Warbixinta farsamada ISA TR96.05.02 - "Tijaabinta Caddeynta Gudaha ee Walxaha Otomaatigga ah" hadda waa la horumarinayaa.
Warbixinta HSE ee UK CRR 428/2002 - "Mabaadi'da tijaabada caddaynta ee nidaamyada qalabka badbaadada ee warshadaha kiimikada" waxay bixisaa macluumaad ku saabsan baaritaanka caddaynta iyo waxa shirkaduhu ka qabanayaan UK.
Habka tijaabada caddeynta wuxuu ku salaysan yahay falanqaynta qaababka guuldarrada khatarta ah ee la yaqaan ee mid kasta oo ka mid ah qaybaha ku jira waddada safarka ee shaqada qalabka badbaadada (SIF), shaqada SIF sida nidaam, iyo sida (iyo haddii) loo tijaabiyo habka guuldarrada khatarta ah. Horumarinta habraaca waa inay ka bilaabataa marxaladda naqshadeynta SIF iyadoo la adeegsanayo naqshadeynta nidaamka, xulashada qaybaha, iyo go'aaminta goorta iyo sida loo caddeeyo tijaabada. Qalabka SIS waxay leeyihiin heerar kala duwan oo adag oo tijaabinta caddaynta ah oo ay tahay in lagu tixgeliyo naqshadeynta SIF, hawlgalka iyo dayactirka. Tusaale ahaan, mitirrada orifice iyo gudbiyeyaasha cadaadiska ayaa ka fudud in la tijaabiyo marka loo eego mitirrada socodka tirada Coriolis, mitirrada mag ama dareemayaasha heerka radar-ka hawada. Naqshadeynta codsiga iyo waalka waxay sidoo kale saameyn kartaa dhammaystirka imtixaanka caddeynta waalka si loo hubiyo in guuldarrooyinka khatarta ah iyo kuwa bilowga ah ee ay sababaan burburka, ku-xidhka ama guuldarrooyinka ku-tiirsan waqtiga aysan horseedin guuldarro muhiim ah muddada tijaabada ee la doortay.
In kasta oo hababka tijaabada caddaynta badanaa la sameeyo inta lagu jiro marxaladda injineernimada SIF, waa in sidoo kale ay dib u eegaan goobta Hay'adda Farsamada SIS, Hawlgallada iyo farsamoyaqaannada qalabka ee samayn doona tijaabada. Sidoo kale waa in la sameeyaa falanqaynta badbaadada shaqada (JSA). Waa muhiim in la helo ogolaanshaha warshadda ee ku saabsan tijaabooyinka la samayn doono iyo goorta, iyo suurtogalnimadooda jireed iyo badqabka. Tusaale ahaan, ma fiicna in la cayimo tijaabada qayb-istaagga marka kooxda Hawlgalladu aysan ogolaan inay sameeyaan. Waxaa sidoo kale lagu talinayaa in hababka tijaabada caddaynta ay dib u eegaan khabiir madax-bannaan oo ku takhasusay mawduuca (SME). Tijaabada caadiga ah ee looga baahan yahay tijaabada caddaynta shaqada oo dhammaystiran waxaa lagu sawiray Jaantuska 1.
Shuruudaha tijaabada xaqiijinta shaqada oo dhammaystiran Jaantuska 1: Tilmaamaha tijaabada xaqiijinta shaqada oo dhammaystiran ee shaqada qalabka badbaadada (SIF) iyo nidaamkeeda qalabka badbaadada (SIS) waa inay qeexaan ama tixraacaan tallaabooyinka isku xigxiga laga bilaabo diyaarinta imtixaanka iyo hababka imtixaanka ilaa ogeysiisyada iyo dukumentiyada.
Jaantuska 1: Tilmaamaha tijaabada ee xaqiijinta shaqada oo dhammaystiran ee shaqada qalabka badbaadada (SIF) iyo nidaamkeeda qalabka badbaadada (SIS) waa inay qeexaan ama tixraacaan tallaabooyinka isku xigxiga laga bilaabo diyaarinta imtixaanka iyo hababka imtixaanka ilaa ogeysiisyada iyo dukumentiyada.
Tijaabada caddeynta waa tallaabo dayactir oo la qorsheeyay oo ay tahay in ay sameeyaan shaqaale karti leh oo ku tababaran baaritaanka SIS, habka caddeynta, iyo wareegyada SIS ee ay tijaabin doonaan. Waa in la sameeyaa baaritaan guud ka hor inta aan la sameynin tijaabada caddeynta bilowga ah, ka dibna waxaa loo diri doonaa hay'adda farsamada SIS si loo hagaajiyo ama loo saxo.
Waxaa jira laba nooc oo guuldarro aasaasi ah (ammaan ah ama khatar ah), kuwaas oo loo qaybiyay afar nooc - khatar ah oo aan la ogaan, khatar ah oo la ogaado (iyadoo lagu ogaanayo ogaanshaha), ammaan ah oo aan la ogaan iyo ammaan ah oo la ogaado. Ereyada guuldarrada khatarta ah iyo kuwa khatarta ah ee aan la ogaan ayaa si isdhaafsan loogu isticmaalaa maqaalkan.
Tijaabada caddeynta SIF, waxaan si gaar ah u xiiseyneynaa qaababka khatarta ah ee aan la ogaan karin ee fashilka, laakiin haddii ay jiraan baaritaanno isticmaale oo ogaanaya cilladaha khatarta ah, baaritaannadan waa in la tijaabiyaa caddeynta. Xusuusnow in si ka duwan baaritaanka isticmaalaha, baaritaanka gudaha ee qalabka badanaa isticmaaluhu ma xaqiijin karo inay shaqeynayaan, tanina waxay saameyn kartaa falsafadda baaritaanka caddeynta. Marka lagu qiimeeyo baaritaanka ogaanshaha xisaabinta SIL, digniinaha ogaanshaha (tusaale ahaan digniinaha ka baxsan fog) waa in la tijaabiyaa iyadoo qayb ka ah baaritaanka caddeynta.
Hababka guuldarada waxaa loo qaybin karaa kuwa la tijaabiyay inta lagu jiro tijaabada caddaynta, kuwa aan la baarin, iyo guuldarrooyinka bilowga ah ama guuldarrooyinka ku xiran waqtiga. Qaar ka mid ah hababka guuldarada khatarta ah waxaa laga yaabaa inaan si toos ah loo baarin sababo kala duwan awgood (tusaale ahaan dhibka, go'aanka injineernimada ama hawlgalka, jaahilnimada, karti la'aanta, khaladaadka ka-tagista ama komishanka nidaamka, suurtagalnimada yar ee dhicitaanka, iwm.). Haddii ay jiraan qaabab guuldarada la yaqaan oo aan la baarin doonin, magdhowga waa in lagu sameeyaa naqshadeynta qalabka, habka tijaabada, beddelka ama dib u dhiska qalabka xilliyeed, iyo/ama baaritaanka male-awaalka waa in la sameeyaa si loo yareeyo saameynta ku yeelan karta hufnaanta SIF ee aan la baarin.
Cilladda bilowga ah waa xaalad ama xaalad hoos u dhac ah oo si macquul ah u dhici karta haddii tallaabooyinka sixitaanka aan si habboon loo qaadin. Badanaa waxaa lagu ogaadaa marka la barbardhigo waxqabadka imtixaanada caddaynta ee ugu dambeeyay ama kuwa bilowga ah (tusaale ahaan saxiixyada waalka ama waqtiyada jawaabta waalka) ama kormeer (tusaale ahaan dekedda habka la xiray). Cilladaha bilowga ah badanaa waxay ku xiran yihiin waqtiga - inta uu qalabka ama isku-dubaridku shaqeynayo, ayay sii xumaanayaan; xaaladaha fududeeya cilladda aan kala sooca lahayn ayaa sii badanaya, habaynta xiridda dekedda ama ururinta dareemayaasha waqti ka dib, cimriga waxtarka leh wuu dhammaadaa, iwm. Sidaa darteed, muddada dheer ee tijaabada caddaynta, waxay u badan tahay inay dhacdo cilladda bilowga ah ama ku tiirsanaanta waqtiga. Ilaalinta kasta ee ka dhanka ah cilladaha bilowga ah sidoo kale waa in la tijaabiyaa caddayn (nadiifinta dekedda, raadinta kulaylka, iwm.).
Habraacyada waa in loo qoraa baaritaanka caddaynta si loo ogaado guuldarrooyinka khatarta ah (aan la ogaan). Habka guuldarrada iyo falanqaynta saamaynta (FMEA) ama farsamooyinka habka guuldarrada, saamaynta iyo falanqaynta ogaanshaha (FMEDA) ayaa kaa caawin kara aqoonsashada guuldarrooyinka khatarta ah ee aan la ogaan, iyo halka ay tahay in la hagaajiyo daboolida baaritaanka caddaynta.
Nidaamyo badan oo tijaabo caddayn ah ayaa ah waayo-aragnimo qoraal ah iyo qaabab laga soo qaatay hababka jira. Nidaamyada cusub iyo SIF-yada aadka u adag waxay u baahan yihiin hab injineernimo badan iyadoo la adeegsanayo FMEA/FMEDA si loo falanqeeyo guuldarrooyinka khatarta ah, loo go'aamiyo sida habka imtixaanku u tijaabin doono ama uusan u tijaabin doonin guuldarrooyinkaas, iyo daboolida imtixaanada. Jaantuska falanqaynta qaabka guuldarrada heerka sare ee dareemaha ayaa lagu muujiyay Jaantuska 2. FMEA caadi ahaan waxay u baahan tahay oo keliya in hal mar la sameeyo nooc gaar ah oo qalab ah oo dib loogu isticmaalo aaladaha la midka ah iyadoo la tixgelinayo adeeggooda habka, rakibidda iyo awoodaha tijaabinta goobta.
Falanqaynta fashilka heerka macro Jaantuska 2: Jaantuskan falanqaynta qaabka guuldarada heerka macro ee loogu talagalay dareemayaasha iyo gudbiyaha cadaadiska (PT) wuxuu muujinayaa shaqooyinka ugu muhiimsan ee badanaa loo qaybin doono falanqayn badan oo fashilka yar yar ah si buuxda loogu qeexo guuldarrooyinka suurtagalka ah ee wax looga qabanayo imtixaanada shaqada.
Jaantuska 2: Jaantuskan falanqaynta qaabka guuldarada heerka sare ee loogu talagalay dareemayaasha iyo gudbiyaha cadaadiska (PT) wuxuu muujinayaa shaqooyinka ugu muhiimsan ee badanaa loo qaybin doono falanqaynno badan oo ku saabsan guuldarada yar yar si si buuxda loogu qeexo guuldarrooyinka suurtagalka ah ee wax looga qabanayo imtixaanada shaqada.
Boqolleyda guuldarrooyinka la yaqaan, khatarta ah, ee aan la ogaan ee lagu tijaabiyay caddaynta waxaa loo yaqaan caymiska tijaabada caddaynta (PTC). PTC waxaa badanaa loo isticmaalaa xisaabinta SIL si loogu "magdhabo" ku guuldareysiga si buuxda u tijaabinta SIF. Dadku waxay aaminsan yihiin inay khaldan yihiin sababtoo ah waxay tixgeliyeen la'aanta caymiska tijaabada ee xisaabinta SIL, inay naqshadeeyeen SIF la isku halleyn karo. Xaqiiqda fudud ayaa ah, haddii caymiskaaga tijaabada uu yahay 75%, oo haddii aad tiradaas ku soo dartay xisaabinta SIL-kaaga oo aad tijaabiso waxyaabaha aad horey u tijaabinaysay si joogto ah, 25% guuldarrooyinka khatarta ah ayaa wali dhici kara tirakoob ahaan. Hubaal ma doonayo inaan ku jiro 25%.
Warbixinnada oggolaanshaha FMEDA iyo buug-gacmeedyada badbaadada ee aaladaha waxay caadi ahaan bixiyaan habka ugu yar ee baaritaanka caddaynta iyo caymiska tijaabada caddaynta. Kuwani waxay bixiyaan oo keliya hagitaan, maaha dhammaan tallaabooyinka tijaabada ee looga baahan yahay habka baaritaanka caddaynta dhammaystiran. Noocyada kale ee falanqaynta guuldarrooyinka, sida falanqaynta geedka cilladaha iyo dayactirka ku salaysan kalsoonida, ayaa sidoo kale loo isticmaalaa in lagu falanqeeyo guuldarrooyinka khatarta ah.
Imtixaanada caddaynta waxaa loo qaybin karaa tijaabo shaqeyneed oo dhammaystiran (dhammaad-ilaa-dhammaad) ama tijaabo shaqeyneed oo qayb ah (Jaantuska 3). Tijaabada shaqeynta qayb ahaan waxaa badanaa la sameeyaa marka qaybaha SIF ay leeyihiin waqtiyo tijaabo oo kala duwan oo ku jira xisaabinta SIL kuwaas oo aan la jaanqaadin xidhitaannada la qorsheeyay ama dib-u-soo-celinta. Waa muhiim in hababka tijaabada caddaynta shaqada qayb ahaan ay isku dhacaan si ay si wadajir ah u tijaabiyaan dhammaan hawlaha badbaadada ee SIF. Tijaabada shaqayneed ee qayb ahaan, weli waxaa lagu talinayaa in SIF ay yeelato tijaabo caddayn bilow ah oo dhammaad-ilaa-dhammaad ah, iyo kuwa xiga inta lagu jiro dib-u-soo-celinta.
Tijaabooyinka caddeynta qayb ahaan waa inay isku daraan Jaantuska 3: Tijaabooyinka caddeynta qayb ahaan ee isku dhafan (hoose) waa inay daboolaan dhammaan shaqooyinka tijaabada caddeynta shaqada oo dhammaystiran (kor).
Jaantuska 3: Tijaabooyinka caddaynta qayb ahaan ee isku dhafan (hoose) waa inay daboolaan dhammaan hawlaha tijaabada caddaynta shaqaynaysa oo dhammaystiran (kor).
Tijaabada caddeynta qayb ahaan waxay tijaabisaa oo keliya boqolkiiba qaababka cilladaha qalabka. Tusaale caadi ah waa tijaabinta waalka qayb ahaan-istaroogga, halkaas oo waalka la dhaqaajiyo xaddi yar (10-20%) si loo xaqiijiyo in uusan ku dheganayn. Tani waxay leedahay dabool tijaabo oo caddayn ah oo ka hooseeya tijaabada caddaynta ee muddada tijaabada koowaad.
Habraacyada imtixaanka caddeynta way ku kala duwanaan karaan dhibka marka loo eego kakanaanta SIF iyo falsafadda habka imtixaanka shirkadda. Shirkadaha qaar waxay qoraan habraacyo tijaabo oo tallaabo-tallaabo ah oo faahfaahsan, halka kuwa kalena ay leeyihiin habraacyo kooban. Tixraacyada habraacyada kale, sida cabbiraadda caadiga ah, mararka qaarkood waxaa loo isticmaalaa in lagu yareeyo cabbirka habka baaritaanka caddeynta iyo in lagu caawiyo hubinta isku-dheelitirka imtixaanka. Habraaca baaritaanka caddeynta ee wanaagsan waa inuu bixiyaa faahfaahin ku filan si loo hubiyo in dhammaan baaritaanka si habboon loo fuliyay oo loo diiwaangeliyey, laakiin aan lahayn faahfaahin badan oo keenaysa in farsamoyaqaannada ay rabaan inay ka boodaan tallaabooyinka. In farsamayaqaanka, oo mas'uul ka ah fulinta tallaabada tijaabada, bilowga tallaabada tijaabada ee la dhammaystiray, ay gacan ka geysan karto hubinta in imtixaanka si sax ah loo samayn doono. Saxeexa imtixaanka caddaynta ee la dhammaystiray ee ay sameeyeen Kormeeraha Qalabka iyo wakiillada Hawlgallada ayaa sidoo kale xoojin doona muhiimadda waxayna hubin doonaan imtixaan caddayn oo si habboon loo dhammaystiray.
Jawaab celinta farsamoyaqaannada waa in had iyo jeer lagu martiqaadaa inay gacan ka geystaan hagaajinta habka. Guusha habka tijaabada caddeynta waxay qayb weyn ka tahay gacanta farsamoyaqaannada, sidaa darteed dadaal wada jir ah ayaa aad loogu talinayaa.
Inta badan baaritaanka caddaynta waxaa badanaa lagu sameeyaa khadka tooska ah inta lagu jiro xiritaanka ama dib u soo celinta. Xaaladaha qaarkood, baaritaanka caddaynta waxaa laga yaabaa in looga baahdo in lagu sameeyo khadka tooska ah inta lagu jiro socodsiinta si loo buuxiyo xisaabinta SIL ama shuruudaha kale. Baaritaanka khadka tooska ah wuxuu u baahan yahay qorsheyn iyo isku-dubarid Hawlgallada si loogu oggolaado baaritaanka caddaynta in si ammaan ah loo sameeyo, iyada oo aan la carqaladeyn habka, iyo iyada oo aan la keenin safar been abuur ah. Waxay qaadataa hal safar oo keliya si loo isticmaalo dhammaan kuwa kaa soo horjeeda. Inta lagu jiro noocan tijaabada ah, marka SIF uusan si buuxda u heli karin si uu u fuliyo hawshiisa badbaadada, 61511-1, Qodobka 11.8.5, wuxuu sheegayaa in "Tallaabooyin magdhow ah oo hubinaya in hawlgal ammaan ah oo sii socda la bixiyo iyadoo la raacayo 11.3 marka SIS ay ku jirto marin-habaabin (dayactir ama tijaabin)." Habka maaraynta xaaladaha aan caadiga ahayn waa inuu la socdaa habka baaritaanka caddaynta si loo hubiyo in tan si habboon loo sameeyo.
SIF waxaa caadi ahaan loo qaybiyaa saddex qaybood oo waaweyn: dareemayaal, xalliyayaal macquul ah iyo walxo kama dambays ah. Waxaa sidoo kale jira aalado kaaliyeyaal ah oo lala xiriirin karo mid kasta oo ka mid ah saddexdan qaybood (tusaale ahaan caqabadaha IS, amps-ka safarka, gudbinta isku xirka, solenoids, iwm.) kuwaas oo sidoo kale la tijaabin karo. Dhinacyada muhiimka ah ee tijaabinta caddaynta mid kasta oo ka mid ah teknoolojiyadan waxaa laga heli karaa dhinaca dambe, "Dareemayaasha tijaabinta, xalliyayaal macquul ah iyo walxaha kama dambayska ah" (hoos).
Waxyaabo qaar ayaa ka fudud in la caddeeyo tijaabada marka loo eego kuwa kale. Tiknoolajiyada socodka iyo heerka ee casriga ah iyo kuwa hore ee yar ayaa ku jira qaybta ugu adag. Kuwaas waxaa ka mid ah mitirrada socodka ee Coriolis, mitirrada vortex, mitirrada mag, radar-ka hawada, heerka ultrasonic, iyo isbeddelada habka gudaha, si aan u xuso dhowr. Nasiib wanaag, qaar badan oo ka mid ah kuwan hadda waxay leeyihiin baaritaanno la xoojiyay oo u oggolaanaya baaritaan la hagaajiyay.
Dhibaatada tijaabinta caddeynta qalabka noocaas ah ee goobta waa in lagu tixgeliyaa naqshadda SIF. Way fududahay injineerinka inuu doorto aaladaha SIF iyada oo aan si dhab ah loo tixgelin waxa loo baahan yahay si loo tijaabiyo caddeynta qalabka, maadaama aysan noqon doonin dadka tijaabinaya. Tani sidoo kale waa run tijaabada qayb-istaagga, taas oo ah hab caadi ah oo lagu hagaajin karo celceliska suurtagalnimada guuldarada SIF marka loo baahdo (PFDavg), laakiin mustaqbalka warshadda Hawlgalladu ma rabaan inay sameeyaan, marar badanna ma rabaan. Had iyo jeer bixi kormeerka warshadda ee injineernimada SIFs marka la eego tijaabinta caddaynta.
Tijaabada caddeynta waa inay ku jirtaa kormeer lagu sameynayo rakibaadda iyo dayactirka SIF sida loogu baahdo si loo waafajiyo 61511-1, Qodobka 16.3.2. Waa in la sameeyaa kormeer kama dambays ah si loo hubiyo in wax walba la xiray, iyo in la labanlaabo hubinta in SIF si habboon loogu celiyay adeegga hawsha.
Qorista iyo hirgelinta habraaca tijaabada wanaagsan waa tallaabo muhiim ah si loo hubiyo hufnaanta SIF inta uu nool yahay. Habka imtixaanku waa inuu bixiyaa faahfaahin ku filan si loo hubiyo in imtixaanada loo baahan yahay si joogto ah oo ammaan ah loo sameeyo oo loo diiwaangeliyo. Guuldarrooyinka khatarta ah ee aan lagu tijaabin tijaabooyinka caddaynta waa in la magdhabaa si loo hubiyo in hufnaanta badbaadada SIF si ku filan loo ilaaliyo inta uu nool yahay.
Qorista habraaca tijaabada caddeynta wanaagsan waxay u baahan tahay hab macquul ah oo lagu falanqeeyo injineernimada ee ku saabsan cilladaha khatarta ah ee iman kara, xulashada hababka, iyo qorista tallaabooyinka tijaabada caddeynta ee ku jira awoodaha tijaabada warshadda. Inta aad socoto, hel fursad aad ku tijaabiso warshadda dhammaan heerarka, oo tababar farsamoyaqaannada si ay u sameeyaan oo u diiwaangeliyaan imtixaanka caddeynta iyo sidoo kale inay fahmaan muhiimadda imtixaanka. Qor tilmaamaha sidii aad tahay farsamo yaqaanka qalabka ee shaqada qaban doona, iyo in noloshu ay ku xiran tahay helitaanka baaritaanka saxda ah, sababtoo ah way sameeyaan.
Testing sensors, logic solvers and final elements A SIF is typically divided up into three main parts, sensors, logic solvers and final elements. There also typically are auxiliary devices that can be associated within each of these three parts (e.g. I.S. barriers, trip amps, interposing relays, solenoids, etc.) that must also be tested.Sensor proof tests: The sensor proof test must ensure that the sensor can sense the process variable over its full range and transmit the proper signal to the SIS logic solver for evaluation. While not inclusive, some of the things to consider in creating the sensor portion of the proof test procedure are given in Table 1. Table 1: Sensor proof test considerations Process ports clean/process interface check, significant buildup noted Internal diagnostics check, run extended diagnostics if available Sensor calibration (5 point) with simulated process input to sensor, verified through to the DCS, drift check Trip point check High/High-High/Low/Low-Low alarms Redundancy, voting degradation Out of range, deviation, diagnostic alarms Bypass and alarms, restrike User diagnostics Transmitter Fail Safe configuration verified Test associated systems (e.g. purge, heat tracing, etc.) and auxiliary components Physical inspection Complete as-found and as-left documentation Logic solver proof test: When full-function proof testing is done, the logic solver’s part in accomplishing the SIF’s safety action and related actions (e.g. alarms, reset, bypasses, user diagnostics, redundancies, HMI, etc.) are tested. Partial or piecemeal function proof tests must accomplish all these tests as part of the individual overlapping proof tests. The logic solver manufacturer should have a recommended proof test procedure in the device safety manual. If not and as a minimum, the logic solver power should be cycled, and the logic solver diagnostic registers, status lights, power supply voltages, communication links and redundancy should be checked. These checks should be done prior to the full-function proof test.Don’t make the assumption that the software is good forever and the logic need not be tested after the initial proof test as undocumented, unauthorized and untested software and hardware changes and software updates can creep into systems over time and must be factored into your overall proof test philosophy. The management of change, maintenance, and revision logs should be reviewed to ensure they are up to date and properly maintained, and if capable, the application program should be compared to the latest backup.Care should also be taken to test all the user logic solver auxiliary and diagnostic functions (e.g. watchdogs, communication links, cybersecurity appliances, etc.).Final element proof test: Most final elements are valves, however, rotating equipment motor starters, variable-speed drives and other electrical components such as contactors and circuit breakers are also used as final elements and their failure modes must be analyzed and proof tested.The primary failure modes for valves are being stuck, response time too slow or too fast, and leakage, all of which are affected by the valve’s operating process interface at trip time. While testing the valve at operating conditions is the most desirable case, Operations would generally be opposed to tripping the SIF while the plant is operating. Most SIS valves are typically tested while the plant is down at zero differential pressure, which is the least demanding of operating conditions. The user should be aware of the worst-case operational differential pressure and the valve and process degradation effects, which should be factored into the valve and actuator design and sizing.Commonly, to compensate for not testing at process operating conditions, additional safety pressure/thrust/torque margin is added to the valve actuator and inferential performance testing is done utilizing baseline testing. Examples of these inferential tests are where the valve response time is timed, a smart positioner or digital valve controller is used to record a valve pressure/position curve or signature, or advance diagnostics are done during the proof test and compared with previous test results or baselines to detect valve performance degradation, indicating a potential incipient failure. Also, if tight shut off (TSO) is a requirement, simply stroking the valve will not test for leakage and a periodic valve leak test will have to be performed. ISA TR96.05.02 is intended to provide guidance on four different levels of testing of SIS valves and their typical proof test coverage, based on how the test is instrumented. People (particularly users) are encouraged to participate in the development of this technical report (contact crobinson@isa.org).Ambient temperatures can also affect valve friction loads, so that testing valves in warm weather will generally be the least demanding friction load when compared to cold weather operation. As a result, proof testing of valves at a consistent temperature should be considered to provide consistent data for inferential testing for the determination of valve performance degradation.Valves with smart positioners or a digital valve controller generally have capability to create a valve signature that can be used to monitor degradation in valve performance. A baseline valve signature can be requested as part of your purchase order or you can create one during the initial proof test to serve as a baseline. The valve signature should be done for both opening and closing of the valve. Advanced valve diagnostic should also be used if available. This can help tell you if your valve performance is deteriorating by comparing subsequent proof test valve signatures and diagnostics with your baseline. This type of test can help compensate for not testing the valve at worst case operating pressures.The valve signature during a proof test may also be able to record the response time with time stamps, removing the need for a stopwatch. Increased response time is a sign of valve deterioration and increased friction load to move the valve. While there are no standards regarding changes in valve response time, a negative pattern of changes from proof test to proof test is indicative of the potential loss of the valve’s safety margin and performance. Modern SIS valve proof testing should include a valve signature as a matter of good engineering practice.The valve instrument air supply pressure should be measured during a proof test. While the valve spring for a spring-return valve is what closes the valve, the force or torque involved is determined by how much the valve spring is compressed by the valve supply pressure (per Hooke’s Law, F = kX). If your supply pressure is low, the spring will not compress as much, hence less force will be available to move the valve when needed. While not inclusive, some of the things to consider in creating the valve portion of the proof test procedure are given in Table 2. Table 2: Final element valve assembly considerations Test valve safety action at process operating pressure (best but typically not done), and time the valve’s response time. Verify redundancy Test valve safety action at zero differential pressure and time valve’s response time. Verify redundancy Run valve signature and diagnostics as part of proof test and compare to baseline and previous test Visually observe valve action (proper action without unusual vibration or noise, etc.). Verify the valve field and position indication on the DCS Fully stroke the valve a minimum of five times during the proof test to help ensure valve reliability. (This is not intended to fix significant degradation effects or incipient failures). Review valve maintenance records to ensure any changes meet the required valve SRS specifications Test diagnostics for energize-to-trip systems Leak test if Tight Shut Off (TSO) is required Verify the command disagree alarm functionality Inspect valve assembly and internals Remove, test and rebuild as necessary Complete as-found and as-left documentation Solenoids Evaluate venting to provide required response time Evaluate solenoid performance by a digital valve controller or smart positioner Verify redundant solenoid performance (e.g. 1oo2, 2oo3) Interposing Relays Verify correct operation, redundancy Device inspection
SIF waxaa caadi ahaan loo qaybiyaa saddex qaybood oo waaweyn, dareemayaal, xalliyayaal macquul ah iyo walxaha kama dambaysta ah. Waxaa sidoo kale jira aalado kaaliyeyaal ah oo lagu xiriirin karo mid kasta oo ka mid ah saddexdan qaybood (tusaale ahaan caqabadaha IS, amps-ka safarka, gudbinta isku xirka, solenoids, iwm.) kuwaas oo sidoo kale la tijaabin karo.
Tijaabooyinka caddeynta dareemaha: Tijaabada caddeynta dareemaha waa inay hubisaa in dareemaha uu dareemi karo isbeddelka habka inta uu ku jiro baaxaddiisa oo dhan isla markaana uu calaamadda saxda ah u gudbin karo xalliyaha macquulka SIS si loo qiimeeyo. In kasta oo aan loo baahnayn, haddana qaar ka mid ah waxyaabaha la tixgelinayo marka la abuurayo qaybta dareemaha ee habka tijaabada caddeynta waxaa lagu bixiyay Shaxda 1.
Tijaabada Cadayga Xallinta Macquulka: Marka la sameeyo tijaabada caddayga shaqada oo buuxda, qaybta xalliyaha macquulka ee ku aaddan fulinta tallaabada badbaadada ee SIF iyo ficillada la xiriira (tusaale ahaan digniinaha, dib u dejinta, boodboodyada, ogaanshaha isticmaalaha, dib-u-habaynta shaqada, HMI, iwm.) ayaa la tijaabiyaa. Tijaabooyinka caddayga shaqada qayb ahaan ama qayb ahaan waa inay fuliyaan dhammaan tijaabooyinkan iyagoo qayb ka ah tijaabooyinka caddayga ee is dulsaaran. Soo saaraha xalliyaha macquulka waa inuu lahaadaa hab tijaabo caddayn ah oo lagu taliyay oo ku jira buugga badbaadada qalabka. Haddii aysan ahayn iyo ugu yaraan, awoodda xalliyaha macquulka waa in la wareejiyaa, diiwaanka ogaanshaha xalliyaha macquulka, nalalka xaaladda, danabyada sahayda korontada, xiriiriyeyaasha isgaarsiinta iyo dib-u-habaynta waa in la hubiyaa. Hubintan waa in la sameeyaa ka hor imtixaanka caddayga shaqada oo dhan.
Ha samayn mala-awaalka ah in barnaamijku uu waligiis wanaagsan yahay oo aan loo baahnayn in la tijaabiyo macquulka ka dib imtixaanka caddaynta bilowga ah maadaama isbeddelada software-ka iyo hardware-ka aan la diiwaan gelin, aan la oggolaan iyo kuwa aan la tijaabin iyo cusboonaysiinta software-ka ay ku soo geli karaan nidaamyada waqti ka dib waana in lagu daraa falsafaddaada guud ee imtixaanka caddaynta. Maareynta diiwaanka isbeddelka, dayactirka, iyo dib-u-eegista waa in dib loo eego si loo hubiyo inay casri yihiin oo si habboon loo dayactiray, haddii ay awood u leedahayna, barnaamijka codsiga waa in la barbar dhigaa kaydka ugu dambeeyay.
Sidoo kale waa in taxaddar la muujiyaa si loo tijaabiyo dhammaan hawlaha kaaliyaha iyo ogaanshaha ee xalliyaasha macquulka ah ee isticmaalaha (tusaale ahaan ilaalada, xiriirka isgaarsiinta, qalabka amniga internetka, iwm.).
Tijaabada kama dambaysta ah ee caddaynta curiyaha: Inta badan curiyayaasha kama dambaysta ah waa waalbaabyo, si kastaba ha ahaatee, qalabka wareegaya ee matoorada, darawallada xawaaraha doorsoomaha leh iyo qaybaha kale ee korontada sida contactors-ka iyo breakers-ka wareegga ayaa sidoo kale loo isticmaalaa walxaha kama dambaysta ah, qaababka guuldarradoodana waa in la falanqeeyaa oo la tijaabiyaa caddayn.
Hababka ugu muhiimsan ee fashilka waalka waa kuwo xayiran, waqtiga jawaab celinta aad ayuu u gaabiyaa ama aad u dhakhso badan yahay, iyo daadashada, kuwaas oo dhammaantood ay saameeyaan is-dhexgalka habka hawlgalka waalka wakhtiga safarka. Iyadoo tijaabinta waalka xaaladaha hawlgalka ay tahay kiiska ugu macquulsan, Hawlgalladu guud ahaan way ka soo horjeedaan in la jebiyo SIF inta warshaddu shaqaynayso. Inta badan waalka SIS waxaa badanaa la tijaabiyaa halka warshaddu ay hoos ugu dhacdo eber cadaadis kala duwan, taas oo ah xaaladaha ugu baahida yar ee hawlgalka. Isticmaaluhu waa inuu ka warqabaa cadaadiska kala duwan ee hawlgalka ugu xun iyo saameynta burburka waalka iyo habka, kuwaas oo lagu darayo naqshadaynta iyo cabbirka waalka iyo dhaqdhaqaaqaha.
Commonly, to compensate for not testing at process operating conditions, additional safety pressure/thrust/torque margin is added to the valve actuator and inferential performance testing is done utilizing baseline testing. Examples of these inferential tests are where the valve response time is timed, a smart positioner or digital valve controller is used to record a valve pressure/position curve or signature, or advance diagnostics are done during the proof test and compared with previous test results or baselines to detect valve performance degradation, indicating a potential incipient failure. Also, if tight shut off (TSO) is a requirement, simply stroking the valve will not test for leakage and a periodic valve leak test will have to be performed. ISA TR96.05.02 is intended to provide guidance on four different levels of testing of SIS valves and their typical proof test coverage, based on how the test is instrumented. People (particularly users) are encouraged to participate in the development of this technical report (contact crobinson@isa.org).
Heerkulka jawiga ayaa sidoo kale saameyn kara culayska is-xoqidda waalka, sidaa darteed tijaabinta waalka cimilada diiran guud ahaan waxay noqon doontaa culayska is-xoqidda ugu yar marka la barbar dhigo hawlgalka cimilada qabow. Natiijo ahaan, tijaabinta caddaynta waalka heerkul joogto ah waa in loo tixgeliyaa inay bixiso xog joogto ah oo loogu talagalay baaritaanka macnaha si loo go'aamiyo burburka waxqabadka waalka.
Walxaha leh boosas caqli badan ama koontaroolaha waalka dijitaalka ah guud ahaan waxay leeyihiin awood ay ku abuuraan saxiix waalka ah oo loo isticmaali karo in lagu kormeero burburka waxqabadka waalka. Saxeexa waalka aasaasiga ah ayaa la codsan karaa qayb ka mid ah dalabkaaga iibsiga ama waxaad abuuri kartaa mid inta lagu jiro tijaabada caddaynta bilowga ah si loogu adeego saldhig. Saxeexa waalka waa in la sameeyaa furitaanka iyo xidhitaanka waalka labadaba. Baadhista waalka horumarsan sidoo kale waa in la isticmaalaa haddii la heli karo. Tani waxay kaa caawin kartaa inaad sheegto haddii waxqabadka waalkaagu uu sii xumaanayo iyadoo la barbar dhigayo saxiixyada waalka tijaabada ee caddaynta iyo ogaanshaha ee xiga iyo aasaaskaaga. Noocan tijaabada ah wuxuu kaa caawin karaa magdhowga inaadan tijaabin waalka cadaadiska hawlgalka ee ugu xun.
Saxeexa waalka inta lagu jiro tijaabada caddeynta ayaa sidoo kale awood u yeelan kara inuu duubo waqtiga jawaabta iyadoo la adeegsanayo shaambada waqtiga, taasoo meesha ka saareysa baahida saacad joojin. Waqtiga jawaab celinta oo kordha waa calaamad muujinaysa burburka waalka iyo culayska is jiidjiidka oo kordha si loo dhaqaajiyo waalka. In kasta oo aysan jirin heerar ku saabsan isbeddellada waqtiga jawaab celinta waalka, qaab taban oo isbeddel ah oo ka yimaada tijaabada caddeynta ilaa tijaabada caddeynta ayaa tilmaamaya luminta suurtagalka ah ee faa'iidada badbaadada waalka iyo waxqabadka. Tijaabada caddeynta waalka SIS ee casriga ah waa inay ku jirtaa saxiixa waalka iyadoo loo eegayo dhaqanka injineernimada wanaagsan.
Cadaadiska saadka hawada ee qalabka waalka waa in la cabbiraa inta lagu jiro tijaabada caddeynta. In kasta oo isha waalka ee waalka soo celinta guga ay tahay waxa xira waalka, xoogga ama xoogga ku lug leh waxaa lagu go'aamiyaa inta isha waalka uu cadaadiyo cadaadiska saadka waalka (sida waafaqsan Sharciga Hooke, F = kX). Haddii cadaadiska saadkaagu hooseeyo, isha ma cadaadin doonto sidaas darteed xoog yar ayaa la heli doonaa si loo dhaqaajiyo waalka marka loo baahdo. In kasta oo aan loo baahnayn, qaar ka mid ah waxyaabaha la tixgelinayo marka la samaynayo qaybta waalka ee habka tijaabada caddeynta waxaa lagu bixiyay Shaxda 2.
Waqtiga boostada: Noofambar-13-2019