Gupima ibimenyetso ni igice cyingenzi mu kubungabunga ubusugire bw'umutekano wa sisitemu zacu zikoresha ibikoresho by'umutekano (SIS) na sisitemu zijyanye n'umutekano (urugero: inzogera zikomeye, sisitemu z'umuriro na gaze, sisitemu zo gufunga ibikoresho, nibindi). Ikizamini cy'ubusugire ni ikizamini gikorwa buri gihe kugira ngo harebwe ko hari ibitagenda neza, hakagezwa imikorere ijyanye n'umutekano (urugero: kongera gukoresha, gufunga, inzogera, gusuzuma, kuzimya intoki, nibindi), no kwemeza ko sisitemu yujuje ibisabwa n'ikigo n'ibyo hanze. Ibisubizo by'ikizamini cy'ubusugire ni igipimo cy'imikorere ya gahunda ya SIS ishingiye ku busugire bw'imikorere n'uburyo sisitemu yizewe.
Uburyo bwo gupima ibimenyetso bukubiyemo intambwe zo gupima kuva ku gushaka impushya, gutanga amatangazo no gukuraho sisitemu yo gupimisha kugeza ku kwemeza ko ibizamini byose byakozwe, kwandika ikizamini cy’ibimenyetso n’ibyavuye mu bipimo byabyo, gusubiza sisitemu mu kazi, no gusuzuma ibyavuye mu bipimo n’ibyavuye mu bipimo byakozwe mbere.
ANSI/ISA/IEC 61511-1, Ingingo ya 16, ivuga ku igeragezwa ry’ibimenyetso bya SIS. Raporo ya tekiniki ya ISA TR84.00.03 – “Ubusugire bw’imikorere mu byuma by’umutekano (SIS),” ivuga ku igeragezwa ry’ibimenyetso kandi ubu iri kuvugururwa, verisiyo nshya iteganijwe gusohoka vuba. Raporo ya tekiniki ya ISA TR96.05.02 – “Isuzuma ry’ibimenyetso bya value zikoresha ikoranabuhanga” ririmo gukorwa.
Raporo ya HSE yo mu Bwongereza CRR 428/2002 - "Amahame yo gupima ibimenyetso by'ibikoresho by'umutekano mu nganda z'ibinyabutabire" atanga amakuru ku gupima ibimenyetso n'ibyo amasosiyete akora mu Bwongereza.
Uburyo bwo gupima ibimenyetso bushingiye ku isesengura ry’uburyo buzwi bwo gutsindwa kw’ibintu mu buryo bwo kwirinda (SIF), imikorere ya SIF nk’uburyo, n’uburyo (na niba) bwo gupima uburyo bwo gutsindwa kw’ibintu mu buryo buteje akaga. Iterambere ry’uburyo rigomba gutangirira mu cyiciro cya SIF cyo gushushanya hamwe n’igishushanyo mbonera cya sisitemu, guhitamo ibice, no kumenya igihe n’uburyo bwo gupima ibimenyetso. Ibikoresho bya SIS bifite urwego rutandukanye rw’ingorane zo gupima ibimenyetso bigomba kwitabwaho mu gushushanya, gukora no kubungabunga SIF. Urugero, ibipimo by’inyuma n’ibikoresho byohereza umuvuduko biroroshye kubigerageza kurusha ibipimo by’ingufu bya Coriolis, ibipimo by’ingufu cyangwa sentire z’urwego rwa radar mu kirere. Imikoreshereze n’imiterere ya valve nabyo bishobora kugira ingaruka ku buryo burambuye ku igeragezwa ry’ingufu kugira ngo harebwe ko gutsindwa kw’ibintu biteje akaga n’ibitangiye gutemba bitewe no kwangirika, gufunga cyangwa gutsindwa bitewe n’igihe bitatera gutsindwa gukomeye mu gihe cy’igerageza cyatoranijwe.
Nubwo uburyo bwo gupima ibimenyetso bukunze gutegurwa mu gihe cy’imashini ya SIF, bugomba no gusuzumwa n’ikigo gishinzwe tekiniki cya SIS, imikorere n’abatekinisiye b’ibikoresho bazakora isuzuma. Isesengura ry’umutekano w’akazi (JSA) naryo rigomba gukorwa. Ni ngombwa kubona uruganda rutanga ibisobanuro ku bizamini bizakorwa n’igihe bizakorwa, hamwe n’ubushobozi bwabyo mu mubiri no mu mutekano. Urugero, ntacyo bimaze kugena isuzuma ry’igice cy’ibizamini mu gihe itsinda ry’ibikorwa ritemera kubikora. Birasabwa kandi ko uburyo bwo gupima ibimenyetso busuzumwa n’inzobere yigenga mu bintu runaka (SME). Isuzuma risanzwe risabwa kugira ngo habeho ikizamini cyuzuye cyerekana ibimenyetso ku ishusho ya 1.
Ibisabwa ku isuzuma ryuzuye ryerekana ko nta kibazo cy’imikorere Ishusho ya 1: Ibisobanuro byuzuye byerekana ko nta kibazo cy’imikorere cy’igikoresho gifite ibikoresho by’umutekano (SIF) na sisitemu yacyo ifite ibikoresho by’umutekano (SIS) bigomba kugaragaza cyangwa kwerekana intambwe zikurikiranye kuva ku gutegura ibizamini n’uburyo bwo kubigerageza kugeza ku imenyesha n’inyandiko.
Ishusho ya 1: Ibisobanuro byuzuye byerekana ko ikizamini cyuzuye gihamya imikorere y’ibikoresho by’umutekano (SIF) na sisitemu yabyo y’ibikoresho by’umutekano (SIS) bigomba kugaragaza cyangwa kwerekana intambwe zikurikiranye kuva ku gutegura ikizamini n’uburyo bwo gukora ikizamini kugeza ku imenyesha n’inyandiko.
Gupima ibimenyetso ni igikorwa giteganyijwe cyo kubungabunga kigomba gukorwa n'abakozi babishoboye bahuguwe mu gupima SIS, uburyo bwo gupima ibimenyetso, n'imirongo ya SIS bazapima. Hagomba kubaho isuzuma ry'uburyo igikorwa kigomba gukorwa mbere yo gukora isuzuma ry'ibanze, no gutanga ibitekerezo ku kigo gishinzwe tekiniki cya SIS nyuma yo kunoza cyangwa gukosora.
Hari uburyo bubiri bw'ibanze bwo gutsindwa (bwizewe cyangwa buteje akaga), bugabanyijemo uburyo bune—ubuteje akaga butagaragara, ubuteje akaga bwabonetse (binyuze mu gusuzuma), ubuteje akaga butagaragara n'ubuteje akaga. Amagambo akoreshwa mu gutsindwa bitagaragara akaga n'ubuteje akaga akoreshwa mu buryo butandukanye muri iyi ngingo.
Mu isuzuma rya SIF, dushishikajwe cyane cyane n'uburyo bwo gutsindwa buteje akaga butagaragara, ariko niba hari uburyo bwo gusuzuma bw'abakoresha bugaragaza ko hari ibibazo bikomeye, ubwo buryo bwo gusuzuma bugomba gupimwa. Menya ko bitandukanye n'uburyo bwo gusuzuma bw'abakoresha, ubusanzwe uburyo bwo gusuzuma bw'ibikoresho budashobora kwemezwa n'umukoresha nk'aho bufite akamaro, kandi ibi bishobora kugira ingaruka ku buryo bwo gusuzuma ibimenyetso. Iyo hafashwe icyemezo cyo gusuzuma mu mibare ya SIL, uburyo bwo gusuzuma (urugero: uburyo bwo gupima buteje akaga) bugomba kugeragezwa nk'igice cy'isuzuma ry'ibimenyetso.
Uburyo bwo gutsindwa bushobora kugabanywamo uburyo bwo gutsindwa mu gihe cy’ikizamini cyo gupima, ubwo bitapimwe, n’ubwo gutsindwa mu ntangiriro cyangwa gutsindwa bitewe n’igihe. Uburyo bumwe bwo gutsindwa bushobora kudapimwa mu buryo butaziguye kubera impamvu zitandukanye (urugero: ingorane, gufata icyemezo cy’ubuhanga cyangwa imikorere, kutamenya, ubushobozi buke, amakosa yakozwe cyangwa gukora, amahirwe make yo kubaho, nibindi). Niba hari uburyo buzwi bwo gutsindwa butazapimwa, hagomba gutangwa indishyi mu gishushanyo mbonera cy’igikoresho, uburyo bwo gupima, gusimbuza igikoresho rimwe na rimwe cyangwa kongera gusana, na/cyangwa hagakorwa isuzuma ry’impinduka kugira ngo bigabanye ingaruka ku busugire bwa SIF bwo kudapima.
Gucika intege kw'ibanze ni imimerere cyangwa imimerere itesha agaciro ku buryo gucika intege gukomeye kandi biteje akaga bishobora kubaho mu gihe hadafashwe ingamba zo gukosora ku gihe. Akenshi bigaragazwa no kugereranya imikorere n'ibizamini biheruka cyangwa bya mbere byerekana ibimenyetso (urugero: ibimenyetso bya valve cyangwa igihe cyo gusubiza valve) cyangwa no kugenzura (urugero: aho icyuma gifunga). Gucika intege kw'ibanze akenshi biterwa n'igihe—uko igikoresho cyangwa ihuriro bimara igihe kinini, niko bigenda birushaho kwangirika; ibintu byoroshya gucika intege ku buryo butunguranye birushaho kwiyongera, gufunga icyuma cyangwa sensor uko igihe kigenda gihita, ubuzima bw'ingirakamaro burangira, nibindi. Kubwibyo, uko igihe cyo gupima ibimenyetso kigenda kirekire, niko gucika intege kw'ibanze cyangwa igihe gishingiye ku gihe. Uburinzi ubwo aribwo bwose bwo kwirinda gucika intege kw'ibanze bugomba no gupimwa ibimenyetso (gukuraho icyuma, gukurikirana ubushyuhe, nibindi).
Uburyo bwo gupima bugomba kwandikwa mu buryo bwo gupima ibimenyetso by’uko hari amakosa akomeye (atagaragaye). Uburyo bwo gupima no gusesengura ingaruka z’ingaruka (FMEA) cyangwa uburyo bwo gupima ingaruka z’ingaruka n’ingaruka z’ingaruka (FMEDA) bushobora gufasha mu kumenya amakosa akomeye ataragaragara, kandi aho uburyo bwo gupima ibimenyetso bugomba kunozwa.
Uburyo bwinshi bwo gupima ibimenyetso bushingira ku bunararibonye bwanditse n'ingero z'uburyo busanzweho. Uburyo bushya na SIF zigoye cyane bisaba uburyo bwateguwe neza bukoresha FMEA/FMEDA kugira ngo hasesengurwe uburyo bwo gupima ibintu buteje akaga, hamenyekane uburyo uburyo bwo gupima buzaba cyangwa butazagerageza ibyo bintu, ndetse n'uburyo ibizamini bishyirwamo. Ishusho ya 2 igaragaza uburyo bwo gupima uburyo bwo gupima ibintu buteje akaga. FMEA ikunze gukorwa rimwe gusa ku bwoko runaka bw'igikoresho kandi igakoreshwa ku bikoresho bisa nabyo hazirikanwa serivisi zabyo, ubushobozi bwo gushyiraho no gupima aho byakorewe.
Isesengura ry’inanirwa ry’urwego rwa macro Ishusho ya 2: Iyi shusho y’agace k’isesengura ry’uburyo bwo gutsindwa kw’urwego rwa macro k’icyuma gipima umuvuduko (PT) igaragaza imikorere y’ingenzi isanzwe igabanywamo ibice byinshi by’isesengura ry’inanirwa ry’urusobe rw’ibintu kugira ngo hamenyekane neza inzitizi zishobora gukemurwa mu bizamini by’imikorere.
Ishusho ya 2: Iyi shusho y'agace k'uburyo bwo gusesengura ikibazo cya macro-level ku cyuma gipima umuvuduko (PT) kigaragaza imikorere y'ingenzi isanzwe igabanywamo ibice byinshi by'isesengura rya microfailure kugira ngo hamenyekane neza imbogamizi zishobora gukemurwa mu bizamini by'imikorere.
Igipimo cy'ibitaragenze neza bizwi, biteje akaga, bitaramenyekana, ariko bikaba byarapimwe byitwa proof test coverage (PTC). PTC ikoreshwa cyane mu mibare ya SIL kugira ngo "yishyure" ku kunanirwa gupima SIF byuzuye. Abantu bafite imyizerere yibeshya ko kubera ko batekereje ku kubura ubwishingizi bw'ibizamini mu mibare yabo ya SIL, bakoze SIF yizewe. Ikintu cyoroshye ni uko, niba ubwishingizi bw'ibizamini byawe ari 75%, kandi niba warashyize uwo mubare mu mibare yawe ya SIL no mu bintu usanzwe ugerageza kenshi, 25% by'ibitaragenze neza bishobora kubaho mu mibare. Sinshaka kuba muri iyo 25%.
Raporo z’ibyemeza bya FMEDA n’amabwiriza y’umutekano ku bikoresho ubusanzwe bitanga uburyo bwo gupima ibimenyetso n’uburyo bwo gupima ibimenyetso. Ibi bitanga ubuyobozi gusa, ntabwo ari intambwe zose zisabwa kugira ngo habeho uburyo bwo gupima ibimenyetso. Ubundi buryo bwo gusesengura amakosa, nko gusesengura igiti cy’amakosa no kubungabunga ubwiza, nabwo bukoreshwa mu gusesengura amakosa ashobora guteza akaga.
Ibizamini by'ubuhamya bishobora kugabanywamo ibizamini byuzuye (kuva ku mpera kugeza ku mpera) cyangwa ibizamini by'imikorere y'igice (Ishusho ya 3). Ibizamini by'imikorere y'igice bikunze gukorwa iyo ibice bya SIF bifite ibihe bitandukanye byo gupima mu mibare ya SIL bidahuye n'ibizamini byateganyijwe cyangwa ibizamini byo guhindukira. Ni ngombwa ko inzira zo gupima ibimenyetso by'imikorere y'igice zihurirana ku buryo hamwe zipima imikorere yose y'umutekano wa SIF. Mu ibizamini by'imikorere y'igice, birasabwa ko SIF igira ikizamini cy'ibanze cyo gupima kuva ku mpera kugeza ku mpera, n'ibindi bikurikiraho mu gihe cyo guhindukira.
Ibizamini by'ubuhamya bw'igice bigomba guteranya Ishusho ya 3: Ibizamini by'ubuhamya bw'igice (hepfo) bigomba gukubiyemo imikorere yose y'ikizamini cyuzuye cy'ubuhamya bw'imikorere (hejuru).
Ishusho ya 3: Ibizamini byashyizwe hamwe byerekana ibimenyetso (hepfo) bigomba gukubiyemo imikorere yose y’ikizamini cyuzuye cyerekana ibimenyetso (hejuru).
Ikizamini cy’ubuhamya bw’igice gipima gusa ijanisha ry’uburyo igikoresho cyananiwe gukora. Urugero rusanzwe ni ikizamini cy’ubushyuhe bw’igice gipima, aho ubushyuhe bwimurwaho gato (10-20%) kugira ngo harebwe ko butahagaze. Ibi bifite ubushyuhe buke mu ikizamini cy’ubuhamya ugereranyije n’ikizamini cy’ubuhamya mu gihe cy’ikizamini cy’ibanze.
Uburyo bwo gupima ibimenyetso bushobora gutandukana bitewe n'ubugoranye bwa SIF na filozofiya y'uburyo bwo gupima isosiyete. Amasosiyete amwe yandika uburyo bwo gupima burambuye intambwe ku yindi, mu gihe andi afite uburyo bugufi. Ibyerekeye ubundi buryo, nko gupima bisanzwe, rimwe na rimwe bikoreshwa mu kugabanya ingano y'uburyo bwo gupima ibimenyetso no gufasha kwemeza ko isuzuma rihoraho. Uburyo bwiza bwo gupima ibimenyetso bugomba gutanga ibisobanuro bihagije kugira ngo isuzuma ryose risohorwe neza kandi ryanditse, ariko nta bisobanuro byinshi cyane bituma abatekinisiye bashaka gusimbuka intambwe. Kugira ngo umuhanga, ushinzwe gukora intambwe y'isuzuma, atangire intambwe y'isuzuma ryuzuye bishobora gufasha kwemeza ko ikizamini kizakorwa neza. Gusinya ikizamini cyuzuye cy'ibimenyetso n'abahagarariye imikorere bizashimangira akamaro no kwemeza ko ikizamini cyuzuye cyuzuye neza.
Ibitekerezo by'abatekinisiye bigomba guhora bitumirwa kugira ngo bifashe kunoza uburyo bwo gukora. Kugira ngo uburyo bwo gukora ikizamini gihamye bugere ku ntego y'umutekinisiye, bityo rero ni ngombwa cyane gukorana.
Isuzuma ryinshi ry’ibimenyetso rikunze gukorwa hanze ya interineti mu gihe cyo guhagarika cyangwa gusimbuza. Hari ubwo, isuzuma ry’ibimenyetso rishobora gusabwa gukorwa kuri interineti mu gihe cyo gukora kugira ngo huzuzwe imibare ya SIL cyangwa ibindi bisabwa. Isuzuma ryo kuri interineti risaba gutegura no guhuza ibikorwa kugira ngo isuzuma ry’ibimenyetso rikorerwe mu mutekano, nta kibazo cy’imikorere, kandi nta ngaruka z’urugendo rw’ibinyoma. Bisaba urugendo rumwe gusa rw’ibinyoma kugira ngo ukoreshe ibintu byawe byose. Muri ubu bwoko bw’isuzuma, iyo SIF itaraboneka neza ngo ikore akazi kayo k’umutekano, 61511-1, Ingingo ya 11.8.5, ivuga ko “Ingamba zo kwishyura zituma imikorere ikomeza mu mutekano zigomba gutangwa hakurikijwe ingingo ya 11.3 iyo SIS iri mu nzira yo kunyuramo (gusana cyangwa gupima).” Uburyo budasanzwe bwo gucunga ibintu bugomba kujyana n’uburyo bwo gusuzuma ibimenyetso kugira ngo bifashe kwemeza ko ibi bikorwa neza.
Ubusanzwe SIF igabanyijemo ibice bitatu by'ingenzi: sensors, logic solvers n'ibintu bya nyuma. Hariho kandi ibikoresho by'inyongera bishobora guhuzwa muri buri gice muri ibi bice bitatu (urugero: IS barriers, trip amps, interposing relay, solenoids, nibindi) bigomba no kugeragezwa. Ibintu by'ingenzi byo gupima ibimenyetso kuri buri koranabuhanga biboneka mu gice cyo ku ruhande, "Testing sensors, logic solvers n'ibintu bya nyuma" (hasi).
Hari ibintu byoroshye gupima ibimenyetso kurusha ibindi. Ikoranabuhanga rigezweho n'irindi koranabuhanga risanzwe riri mu cyiciro kigoye cyane. Harimo ibipimo by'amazi bya Coriolis, ibipimo by'amazi ya vortex, ibipimo by'amashanyarazi, radar inyura mu kirere, urwego rwa ultrasound, na switch zikoreshwa mu buryo bw'ikoranabuhanga, ni ukuvuga bike muri byo. Ku bw'amahirwe, byinshi muri ibi ubu bifite uburyo bwo gusuzuma bunoze butuma habaho isuzuma ryiza.
Ingorane zo gupima ibimenyetso nk'ibi mu rwego rw'ikoranabuhanga zigomba kwitabwaho mu gishushanyo cya SIF. Biroroshye ko injeniyeri ihitamo ibikoresho bya SIF idatekereje cyane ku byakenerwa kugira ngo igeragezwa ry'ibikoresho rikoreshwe, kuko atari bo bazaba babigerageza. Ibi ni ko bimeze no ku igeragezwa rya partial-stroke, ari bwo buryo busanzwe bwo kongera amahirwe y'impuzandengo ya SIF yo gutsindwa igihe cyose bikenewe (PFDavg), ariko nyuma imikorere y'uruganda ntishaka kubikora, kandi inshuro nyinshi ishobora kutabikora. Buri gihe shyira imbere uruganda mu buhanga bwa SIF mu bijyanye no gupima ibimenyetso.
Isuzuma ry’ibimenyetso rigomba kuba rikubiyemo igenzura ry’ishyirwaho rya SIF n’isana ryayo uko bikenewe kugira ngo huzuzwe ingingo ya 61511-1, Ingingo ya 16.3.2. Hagomba kubaho igenzura rya nyuma kugira ngo hamenyekane ko byose byafunguwe, no kugenzura kabiri ko SIF yongeye gushyirwa mu bikorwa neza.
Kwandika no gushyira mu bikorwa uburyo bwiza bwo gupima ni intambwe y'ingenzi kugira ngo SIF ikomeze kuba nziza mu gihe cyose ikiriho. Uburyo bwo gupima bugomba gutanga ibisobanuro bihagije kugira ngo ibizamini bikenewe bikorwe neza kandi bikorwe mu buryo buhamye kandi bwizewe. Gutsindwa nabi bitapimwe hakoreshejwe ibimenyetso bigomba kwishyurwa kugira ngo umutekano wa SIF ukomeze kuba mwiza mu gihe cyose ikiriho.
Kwandika uburyo bwiza bwo gupima ibimenyetso bisaba uburyo bufatika bwo gusesengura ibizamini by’ubuhanga ku byangiritse bishobora kubaho, guhitamo uburyo, no kwandika intambwe zo gupima ibimenyetso biri mu bushobozi bw’uruganda bwo gupima. Muri icyo gihe, shaka uruganda rushobora gukoresha mu gupima ku nzego zose, kandi utoze abatekinisiye gukora no kwandika ikizamini cy’ibimenyetso ndetse no gusobanukirwa akamaro k’ikizamini. Andika amabwiriza nk’aho uri umutekinisiye w’ibikoresho ugomba gukora akazi, kandi ko ubuzima bushingiye ku gukora ikizamini neza, kuko ari bo babikora.
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
Ubusanzwe SIF igabanyijemo ibice bitatu by'ingenzi, sensors, logic solvers n'ibintu bya nyuma. Ubusanzwe hariho kandi ibikoresho by'inyongera bishobora guhuzwa muri buri gice muri ibi bice bitatu (urugero: IS barriers, trip amps, interposing relay, solenoids, nibindi) bigomba no kugeragezwa.
Ibizamini byo gupima ibimenyetso: Ikizamini cyo gupima ibimenyetso bigomba kwemeza ko sensor ishobora kumva impinduka mu mikorere yayo yose no kohereza ikimenyetso gikwiye kuri SIS logic solver kugira ngo gisuzumwe. Nubwo bitakubiyemo ibintu byinshi, bimwe mu bintu byo kuzirikana mu gukora igice cya sensor mu isuzuma ry’ibimenyetso bitangwa mu mbonerahamwe ya 1.
Ikizamini cyo gupima imikorere y'amakuru: Iyo ikizamini cyuzuye cy'amakuru gikozwe, uruhare rw'umusesenguzi wa logic mu kurangiza igikorwa cya SIF cy'umutekano n'ibikorwa bifitanye isano (urugero: alarms, reset, bypasses, user diagnostics, redundancies, HMI, nibindi) birageragezwa. Ibizamini by'imikorere y'igice cyangwa igice bigomba gukora ibi bizamini byose nk'igice cy'ibizamini by'amakuru bihurirana. Uruganda rukora logic solution rugomba kugira uburyo bwo gupima imikorere y'amakuru busabwa mu gitabo cy'umutekano w'igikoresho. Bitabaye ibyo kandi byibuze, ingufu za logic solution zigomba guhindurwa, kandi registers zo gusuzuma logic solution, amatara ya status, voltages z'amashanyarazi, itumanaho n'igabanuka ry'amakuru bigomba kugenzurwa. Iri genzura rigomba gukorwa mbere y'ikizamini cyuzuye cy'amakuru.
Ntugatekereze ko porogaramu ari nziza iteka ryose kandi ko logique idakwiye kugeragezwa nyuma y'ikizamini cya mbere cy'ubuhamya kuko impinduka za porogaramu n'ibikoresho bitarakozweho, bitaremewe kandi bitaragenzuwe hamwe n'ivugurura rya porogaramu bishobora kwinjira muri sisitemu uko igihe kigenda gihita kandi bigomba kwitabwaho muri filozofiya yawe rusange y'ikizamini cy'ubuhamya. Imicungire y'inyandiko z'impinduka, kubungabunga, no gusubiramo igomba gusuzumwa kugira ngo harebwe ko zigezweho kandi zibungabunzwe neza, kandi niba zishoboye, porogaramu igomba kugereranywa n'inyandiko iheruka gusubizwamo.
Hakwiye kandi kwitonda mu gupima imikorere yose y’ubufasha mu gukemura ibibazo by’abakoresha (urugero: abashinzwe kugenzura, itumanaho, ibikoresho by’umutekano w’ikoranabuhanga, nibindi).
Ikizamini cya nyuma cyo kwirinda ibintu: Ibintu byinshi bya nyuma ni valves, icyakora, moteri zitangira ibikoresho zizunguruka, moteri zihindura umuvuduko n'ibindi bikoresho by'amashanyarazi nka contactors na circuit breakers nabyo bikoreshwa nk'ibintu bya nyuma kandi uburyo bwo gucika intege kwazo bugomba gupimwa no gupimwa ibimenyetso.
Uburyo bw'ibanze bwo gucika intege kw'amavali ni uguhagarara, igihe cyo gusubiza kigenda buhoro cyane cyangwa vuba cyane, ndetse no gusohoka kw'amazi, byose bigirwaho ingaruka n'uburyo valve ikora mu gihe cyo kunyuramo. Nubwo gupima valve mu gihe cyo gukora ari byo byifuzwa cyane, muri rusange ibikorwa byarwanya gutemba SIF mu gihe uruganda rukora. Amavali menshi ya SIS akunze kugeragezwa mu gihe uruganda rufite umuvuduko wa zero, ibyo bikaba ari byo bidasaba cyane mu mikorere. Umukoresha agomba kumenya umuvuduko mubi cyane w'imikorere ndetse n'ingaruka za valve n'imikorere yayo, ibyo bikaba bigomba gushyirwa mu miterere n'ingano ya valve na actuator.
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).
Ubushyuhe buri hagati y’ikirere bushobora kandi kugira ingaruka ku mikorere y’ingufu z’amashanyarazi, ku buryo ingufu zo gupima mu gihe cy’ubushyuhe muri rusange ziba umutwaro woroshye wo guhindagurika ugereranije n’imikorere y’igihe cy’ubukonje. Kubera iyo mpamvu, gupima ingufu z’amashanyarazi ku bushyuhe busanzwe bigomba gufatwa nk’aho bitanga amakuru ahoraho yo gupima ingufu z’amashanyarazi kugira ngo hamenyekane niba imikorere y’ingufu z’amashanyarazi yangiritse.
Valve zifite imiterere y’ubwenge cyangwa icyuma gipima amashanyarazi muri rusange zifite ubushobozi bwo gukora ikimenyetso cya valve gishobora gukoreshwa mu kugenzura imikorere ya valve. Igice cy’ibanze cya valve gishobora gusabwa nk'igice cy'ibyo waguze cyangwa ushobora kugikora mu isuzuma rya mbere ry’ibimenyetso kugira ngo gikore nk'icyitegererezo. Igice cy’ibanze cya valve kigomba gukorwa haba mu gufungura no gufunga valve. Gusuzuma amashanyarazi mu buryo buhanitse bigomba no gukoreshwa niba bihari. Ibi bishobora kugufasha kumenya niba imikorere ya valve yawe iri kugenda nabi ugereranije ibimenyetso bya valve n’ibizamini bya valve bikurikira n’icyitegererezo cyawe. Ubu bwoko bw’ibizamini bushobora gufasha kwishyura igihe utapimye valve mu gihe cy’ingufu zikomeye zikoreshwa.
Ikimenyetso cya valve mu gihe cyo gupima ibimenyetso gishobora kandi kuba cyandika igihe cyo gusubiza hakoreshejwe ibimenyetso by'igihe, bigakuraho ko isaha yo guhagarara ikenewe. Kongera igihe cyo gusubiza ni ikimenyetso cy'uko valve yangiritse kandi umutwaro wo gukurura urushaho kwiyongera kugira ngo valve yimure. Nubwo nta bipimo ngenderwaho bihari ku bijyanye n'impinduka mu gihe cyo gupima ibimenyetso, impinduka mbi kuva ku isuzuma ry'ibimenyetso kugeza ku isuzuma ry'ibimenyetso bigaragaza ko valve ishobora gutakaza ingano y'umutekano n'imikorere yayo. Isuzuma ry'ubu rijyanye na valve ya SIS rigomba kuba rikubiyemo ikimenyetso cya valve nk'uburyo bwiza bwo gukora imashini.
Umuvuduko w'umwuka utangwa n'igikoresho cya valve ugomba gupimwa mu gihe cyo gupima. Nubwo impera ya valve kuri valve isubiza impera ari yo ifunga valve, imbaraga cyangwa torque bikoreshwa bigenwa n'ingano y'impera ya valve ikandamizwa n'umuvuduko w'impera ya valve (nk'uko itegeko rya Hooke ribivuga, F = kX). Niba umuvuduko w'impera yawe uri hasi, isoko ntizakandamizwa cyane, bityo imbaraga nke zizaboneka zo kwimura valve igihe bibaye ngombwa. Nubwo bitakubiyemo, bimwe mu bintu byo kuzirikana mu gukora igice cya valve mu gikorwa cyo gupima ibimenyetso bitangwa mu mbonerahamwe ya 2.
Igihe cyo kohereza: Ugushyingo-13-2019