Ko te whakamātautau whakamātautau he wāhanga nui o te pupuri i te pono o te haumaru o ā mātou pūnaha taputapu haumaru (SIS) me ngā pūnaha e pā ana ki te haumaru (hei tauira, ngā whakaoho nui, ngā pūnaha ahi me te hau, ngā pūnaha raka taputapu, me ētahi atu). Ko te whakamātautau whakamātautau he whakamātautau ā-wā hei kite i ngā hapa morearea, hei whakamātautau i ngā mahi e pā ana ki te haumaru (hei tauira, te tautuhi anō, te karo, ngā whakaoho, te tātaritanga, te kati ā-ringa, me ētahi atu), me te whakarite kia tutuki te pūnaha i ngā paerewa a te kamupene me ngā paerewa o waho. Ko ngā hua o te whakamātautau whakamātautau he ine anō hoki i te whai huatanga o te kaupapa pono o te mīhini SIS me te pono o te pūnaha i te mara.
Kei roto i ngā tukanga whakamātautau taunakitanga ngā mahi whakamātautau mai i te whiwhi whakaaetanga, te tuku whakamōhiotanga me te tango i te pūnaha mai i te whakamahi hei whakamātautau, tae atu ki te whakarite i te whakamātautau whānui, te tuhi i te whakamātautau taunakitanga me ōna hua, te whakahoki i te pūnaha ki te whakamahi, me te aromatawai i ngā hua whakamātautau o nāianei me ngā hua whakamātautau taunakitanga o mua.
Ko te ANSI/ISA/IEC 61511-1, Rārangi 16, e kapi ana i te whakamātautau ārai SIS. Ko te pūrongo hangarau ISA TR84.00.03 – “Te Tikanga Pūkaha o ngā Pūnaha Haumaru me ngā Taputapu (SIS),” e kapi ana i te whakamātautau ārai, ā, kei te whakahoutia i tēnei wā, me te tumanako ka puta he putanga hou i ngā wā tata nei. Ko te pūrongo hangarau ISA TR96.05.02 – “Te Whakamātautau Ārai ā-Tūnga o ngā Takirere Aunoa” kei te whakawhanakehia i tēnei wā.
Kei roto i te pūrongo HSE o te UK CRR 428/2002 – "Ngā mātāpono mō te whakamātautau taunakitanga o ngā pūnaha taputapu haumaru i roto i te umanga matū" ngā mōhiohio e pā ana ki te whakamātautau taunakitanga me ngā mahi a ngā kamupene i te UK.
Ko te tukanga whakamātautau whakamātautau e ahu mai ana i te tātari i ngā momo rahunga morearea e mōhiotia ana mō ia wāhanga i roto i te ara haerenga mahi haumaru taputapu (SIF), te mahi SIF hei pūnaha, me pēhea (mehemea rānei) te whakamātautau mō te aratau rahunga morearea. Me tīmata te whakawhanaketanga tukanga i te wāhanga hoahoa SIF me te hoahoa pūnaha, te kōwhiringa o ngā wāhanga, me te whakatau i te wā me te pēhea o te whakamātautau whakamātautau. He rerekē ngā taumata uaua o ngā taputapu SIS ki te whakamātautau whakamātautau me whai whakaaro ki te hoahoa, te whakahaere me te tiaki SIF. Hei tauira, he māmā ake te whakamātautau i ngā mita kōhao me ngā tuku pēhanga i ngā mita rere papatipu Coriolis, ngā mita mag, ngā pūoko taumata radar rānei. Ka taea hoki e te tono me te hoahoa takirere te pā ki te whānui o te whakamātautau ārai takirere kia kore ai ngā rahunga morearea me ngā rahunga tīmatanga nā te hekenga, te mono, ngā rahunga e whakawhirinaki ana ki te wā rānei e arahi ki tētahi rahunga nui i roto i te wā whakamātautau kua tohua.
Ahakoa e whakawhanakehia ana ngā tikanga whakamātautau whakamātautau i te wā o te hangarau SIF, me arotake anō hoki e te Mana Hangarau SIS o te papaanga, ngā Mahi Whakahaere me ngā tohunga taputapu e mahi ana i te whakamātautau. Me mahi anō hoki he tātaritanga haumaru mahi (JSA). He mea nui kia whiwhi i te tautoko a te tipu mō ngā whakamātautau ka mahia me te wā, me ō rātou āheinga ā-tinana me te haumaru. Hei tauira, kāore he pai ki te tohu i te whakamātautau whiu-wāhanga ina kore te rōpū Mahi e whakaae ki te mahi. E taunakihia ana hoki kia arotakehia ngā tikanga whakamātautau whakamātautau e tētahi tohunga kaupapa motuhake (SME). Ko te whakamātautau noa e hiahiatia ana mō te whakamātautau whakamātautau mahi katoa e whakaaturia ana i te Pikitia 1.
Ngā whakaritenga whakamātautau whakamātautau mahi katoa Pikitia 1: Me whakamārama, me tohu rānei i ngā mahi i roto i te raupapa mai i ngā whakaritenga whakamātautau me ngā tukanga whakamātautau ki ngā whakamōhiotanga me ngā tuhinga i roto i te whakatakotoranga whakamātautau mahi katoa mō tētahi mahi taputapu haumaru (SIF) me tana pūnaha taputapu haumaru (SIS).
Pikitia 1: Me whakamārama, me tohu rānei i ngā mahi katoa e whakaatuhia ana i roto i te whakatakotoranga whakamātautau whakamātautau mō tētahi mahi taputapu haumaru (SIF) me tana pūnaha taputapu haumaru (SIS) i ngā mahi i roto i te raupapa mai i ngā whakaritenga whakamātautau me ngā tukanga whakamātautau ki ngā whakamōhiotanga me ngā tuhinga.
Ko te whakamātautau whakamātautau he mahi tiaki kua whakaritea, me mahi e ngā tāngata mātau kua whakangungua ki te whakamātautau SIS, te tukanga whakamātautau, me ngā takahuri SIS ka whakamatautauria e rātou. Me tirotirohia te tukanga i mua i te whakahaere i te whakamātautau whakamātautau tuatahi, ā, me tuku urupare ki te Mana Hangarau SIS o te papaanga i muri mai mō ngā whakapainga, ngā whakatikatika rānei.
E rua ngā momo rahunga matua (haumaru, morearea rānei), e wehea ana kia whā ngā momo—morearea kāore i kitea, morearea kua kitea (mā te tātaritanga), haumaru kāore i kitea, me te haumaru kua kitea. E whakamahia ngātahitia ana ngā kupu morearea me te morearea kāore i kitea i roto i tēnei tuhinga.
I roto i te whakamātautau ārai SIF, ko te mea nui ko ngā aratau rahunga morearea kāore i kitea, engari ki te mea he tātaritanga kaiwhakamahi e kite ana i ngā rahunga morearea, me whakamātautau i ēnei tātaritanga. Kia mahara, he rerekē ki ngā tātaritanga kaiwhakamahi, ko ngā tātaritanga ā-roto o te taputapu kāore e taea te whakamana e te kaiwhakamahi he mahi, ā, ka pā pea tēnei ki te rapunga whakaaro whakamātautau ārai. Ina tangohia te whiwhinga mō ngā tātaritanga i roto i ngā tataunga SIL, me whakamātautau ngā whakaoho tātaritanga (hei tauira, ngā whakaoho i waho o te awhe) hei wāhanga o te whakamātautau ārai.
Ka taea te wehewehe anō i ngā momo rahunga ki ngā mea i whakamatautauria i te wā o te whakamātautau whakamātautau, ngā mea kāore i whakamatautauria, me ngā rahunga tīmatanga, ngā rahunga e whakawhirinaki ana ki te wā. Tērā pea kāore e whakamatautauria tika ētahi momo rahunga morearea mō ngā take maha (hei tauira, te uauatanga, te whakatau hangarau, te whakatau whakahaere rānei, te kore mōhio, te koretake, te hapa pūnaha i mahue, i mahia rānei, te iti o te tūponotanga o te puta, me ētahi atu). Mēnā he momo rahunga e mōhiotia ana kāore e whakamatautauria, me mahi he utu i roto i te hoahoa taputapu, te tukanga whakamātautau, te whakakapinga taputapu, te hanga anō rānei i ia wā, me/ranei te whakamātautau whakatau hei whakaiti i te pānga ki te pono o te kore whakamātautau ki te SIF.
Ko te rahunga tīmatanga he āhua, he āhua rānei e heke ai te taumata, e taea ai te tumanako ka puta he rahunga nui, morearea mena kāore e mahia ngā mahi whakatikatika i te wā tika. I te nuinga o te wā ka kitea ēnei mā te whakataurite i te mahi ki ngā whakamātautau tohu paearu hou, tuatahi rānei (hei tauira, ngā waitohu takirere, ngā wā urupare takirere rānei) mā te tirotiro rānei (hei tauira, he tauranga tukanga kua monohia). Ko ngā rahunga tīmatanga he mea whakawhirinaki ki te wā—ko te roa o te mahi a te taputapu, te huihuinga rānei, ka nui ake te hekenga; ko ngā āhuatanga e āwhina ana i te rahunga matapōkere ka nui ake te tūponotanga, te mono i te tauranga tukanga, te hanga pūoko rānei i roto i te wā, kua pau te roa o te wā whai hua, me ētahi atu. Nō reira, ko te roa o te wā whakamātautau tohu, ko te tūponotanga ka puta he rahunga tīmatanga, he rahunga wā rānei. Me whakamātautau hoki ngā parenga katoa mō ngā rahunga tīmatanga (te horoi tauranga, te whai wera, me ētahi atu).
Me tuhi ngā tukanga hei whakamātautau i ngā hapa morearea (kāore i kitea). Mā ngā tikanga tātari aratau me te pānga hapa (FMEA) me te tātari aratau, pānga me te tātari tātaritanga (FMEDA) ka āwhina i te tautuhi i ngā hapa morearea kāore i kitea, me te wāhi me whakapai ake te kapinga whakamātautau taunakitanga.
He maha ngā tukanga whakamātautau whakamātautau he mea tuhituhi i runga i ngā wheako me ngā tauira mai i ngā tukanga o nāianei. Ko ngā tukanga hou me ngā SIF uaua ake e hiahia ana ki tētahi huarahi hangarau ake mā te whakamahi i te FMEA/FMEDA hei tātari i ngā hapa morearea, hei whakatau me pēhea te whakamātautau, te kore rānei e whakamātautau a te tukanga whakamātautau mō aua hapa, me te kapinga o ngā whakamātautau. Kei te Pikitia 2 tētahi tūtohi poraka tātari aratau hapa taumata-rahi mō tētahi pūoko. Ko te tikanga me mahi kotahi noa te FMEA mō tētahi momo taputapu motuhake, ā, me whakamahi anō mō ngā taputapu rite me te whai whakaaro ki ā rātou ratonga tukanga, tāutanga me ngā āheinga whakamātautau pae.
Tātaritanga rahunga taumata-macro Pikitia 2: E whakaatu ana tēnei hoahoa poraka tātaritanga aratau rahunga taumata-macro mō te pūoko me te tuku pehanga (PT) i ngā mahi matua ka wehea kia maha ngā tātaritanga rahunga moroiti hei tautuhi katoa i ngā rahunga pea hei aro atu ki ngā whakamātautau mahi.
Pikitia 2: E whakaatu ana tēnei hoahoa poraka tātari aratau rahunga taumata-macro mō tētahi pūoko me tētahi tuku pehanga (PT) i ngā mahi matua ka wehea kia maha ngā tātari rahunga moroiti hei tautuhi katoa i ngā rahunga pea hei aro atu ki ngā whakamātautau mahi.
Ko te ōrau o ngā hapa e mōhiotia ana, e morearea ana, e kore e kitea, kua whakamatautauria kia kitea, ka kiia ko te kapinga whakamātautau whakaatu (PTC). He mea whakamahi noa te PTC i roto i ngā tataunga SIL hei "whakakapi" mō te korenga ki te whakamātautau katoa i te SIF. He whakaaro hē tā te tangata nā te mea kua whakaarohia e rātou te korenga o te kapinga whakamātautau i roto i tā rātou tataunga SIL, kua hangaia e rātou he SIF pono. Ko te mea māmā noa iho, mēnā ko tō kapinga whakamātautau he 75%, ā, mēnā i whakaurua taua tau ki roto i tō tataunga SIL, ā, i whakamātauria ngā mea e whakamātautauhia ana e koe i ngā wā katoa, ka taea tonu te puta mai i te 25% o ngā hapa morearea i runga i te tatauranga. Kāore rawa ahau e hiahia kia uru atu ki taua 25%.
Ko ngā pūrongo whakaae a te FMEDA me ngā pukapuka ā-ringa haumaru mō ngā taputapu e whakarato ana i tētahi tukanga whakamātautau iti rawa me te kapinga whakamātautau whakamātautau. He aratohu noa iho ēnei, ehara i te mea ko ngā mahi whakamātautau katoa e hiahiatia ana mō tētahi tukanga whakamātautau whakamātautau whānui. Ko ētahi atu momo tātari rahunga, pērā i te tātari rākau hapa me te tiaki e aro ana ki te pono, ka whakamahia hoki hei tātari mō ngā rahunga morearea.
Ka taea te wehewehe i ngā whakamātautau whakamātautau ki te whakamātautau mahi katoa (mai i te pito ki te pito) me te whakamātautau mahi wāhanga rānei (Pikitia 3). Ko te whakamātautau mahi wāhanga ka mahia i te nuinga o te wā ina he rerekē ngā wā whakamātautau o ngā wāhanga o te SIF i roto i ngā tataunga SIL kāore e rite ki ngā kati me ngā huringa kua whakaritea. He mea nui kia taupatupatu ngā tukanga whakamātautau whakamātautau mahi wāhanga kia whakamatautauria ngātahitia ai ngā mahi haumaru katoa o te SIF. Mō te whakamātautau mahi wāhanga, e taunakihia tonutia ana kia whai whakamātautau whakamātautau tuatahi mai i te pito ki te pito te SIF, me ērā i muri mai i te wā o ngā huringa.
Me tāpiri ngā whakamātautau whakamātautau wāhanga. Pikitia 3: Me kapi i ngā whakamātautau whakamātautau wāhanga kua whakakotahitia (raro) ngā mahi katoa o tētahi whakamātautau whakamātautau mahi katoa (runga).
Pikitia 3: Me kapi katoa ngā mahi a te whakamātautau whakamātautau mahi katoa (runga) i ngā whakamātautau whakamātautau wāhanga whakakotahi (raro).
Ko te whakamātautau whakamātautau ā-wāhanga ka whakamātautau noa i te ōrau o ngā momo rahunga o te taputapu. Ko tētahi tauira noa ko te whakamātautau takirere whiu-wāhanga, ka nekehia te takirere i tētahi wāhi iti (10-20%) hei whakaū kāore i te mau. He iti ake te kapinga whakamātautau whakamātautau o tēnei i te whakamātautau whakamātautau i te wā whakamātautau tuatahi.
Ka rerekē pea te uaua o ngā tukanga whakamātautau whakamātautau i runga i te uaua o te SIF me te rapunga whakaaro o te tukanga whakamātautau a te kamupene. Ka tuhia e ētahi kamupene he tukanga whakamātautau taipitopito, he tukanga poto noa iho ā ētahi. I ētahi wā ka whakamahia ngā tohutoro ki ētahi atu tukanga, pērā i te whakatikatika paerewa, hei whakaiti i te rahi o te tukanga whakamātautau whakamātautau, hei āwhina hoki ki te whakarite kia rite te whakamātautau. Me whakarato he taipitopito nui ki tētahi tukanga whakamātautau whakamātautau pai hei whakarite kia oti pai, kia tuhia hoki ngā whakamātautau katoa, engari kaua e nui rawa ngā taipitopito hei akiaki i ngā tohunga hangarau ki te peke i ngā taahiraa. Mā te tohunga hangarau, te kawenga mō te mahi i te taahiraa whakamātautau, e tīmata te taahiraa whakamātautau kua oti, ka āwhina i te whakarite kia tika te mahi o te whakamātautau. Mā te hainatanga o te whakamātautau whakamātautau kua oti e te Kaiwhakahaere Taputapu me ngā māngai Mahi ka whakanui anō hoki i te hiranga me te whakarite kia oti pai te whakamātautau whakamātautau.
Me tono tonu ki ngā urupare a ngā tohunga hangarau hei āwhina i te whakapai ake i te tukanga. Ko te angitu o tētahi tukanga whakamātautau taunakitanga kei roto i ngā ringa o ngā tohunga hangarau, nō reira he mea tino taunaki kia mahi tahi.
Ko te nuinga o ngā whakamātautau taunakitanga ka mahia i waho o te ipurangi i te wā e kati ana, e huri ana rānei. I ētahi wā, me mahi pea te whakamātautau taunakitanga i runga ipurangi i te wā e whakahaerehia ana hei whakatutuki i ngā tataunga SIL, i ētahi atu whakaritenga rānei. Me whakamahere me te mahi tahi me ngā Mahi Whakahaere mō te whakamātautau ipurangi kia taea ai te mahi haumaru i te whakamātautau taunakitanga, me te kore e whakararuraru i te tukanga, me te kore hoki e puta he hinganga rūpahu. Kotahi noa te haerenga rūpahu hei pau i ō attaboy katoa. I roto i tēnei momo whakamātautau, ina kore te SIF e tino wātea ki te mahi i tana mahi haumaru, e kī ana te 61511-1, te Rārangi 11.8.5, "Me whakarato ngā mahi utu hei whakarite kia haere tonu te mahi haumaru i runga anō i te 11.3 ina kei te taha taha (whakatikatika, whakamātautau rānei) te SIS." Me haere tahi tētahi tukanga whakahaere āhuatanga rerekē me te tukanga whakamātautau taunakitanga hei āwhina i te whakarite kia tika te mahi.
E toru ngā wāhanga matua o te SIF: ngā pūoko, ngā kaiwhakaoti arorau me ngā huānga whakamutunga. He maha anō hoki ngā taputapu āwhina ka taea te hono atu ki roto i ia o ēnei wāhanga e toru (hei tauira, ngā ārai IS, ngā amps trip, ngā relays interposing, ngā solenoids, me ētahi atu) me whakamātautau anō hoki. Kei te paetaha, "Te whakamātautau i ngā pūoko, ngā kaiwhakaoti arorau me ngā huānga whakamutunga" ngā āhuatanga matua o te whakamātautau taunakitanga i ia o ēnei hangarau (kei raro).
He māmā ake te whakamātautau i ētahi mea i ētahi atu. He maha ngā hangarau rere me te taumata hou me ētahi tawhito kei roto i te wāhanga uaua ake. Kei roto i ēnei ko ngā mita rere Coriolis, ngā mita vortex, ngā mita mag, te radar through-the-air, te taumata ultrasonic, me ngā pana tukanga in-situ, hei tauira noa iho. He waimarie, he maha o ēnei inaianei kua whakarei ake i ngā tātaritanga e āhei ai te whakamātautau pai ake.
Me whai whakaaro ki te uauatanga o te whakamātautau i tētahi taputapu pēnei i te mara i roto i te hoahoa SIF. He māmā noa iho mā te hunga hangarau te whiriwhiri i ngā taputapu SIF me te kore e whai whakaaro nui ki ngā mea e hiahiatia ana hei whakamātautau i te taputapu, nā te mea ehara rātou i te hunga e whakamātautau ana i a rātou. He pono anō hoki tēnei mō te whakamātautau whiu-wāhanga, he huarahi noa tēnei hei whakapai ake i te tūponotanga toharite o te rahunga i runga i te tono a te SIF (PFDavg), engari i muri mai kāore te Tari Whakahaere o te tipu e hiahia ki te mahi i tēnei, ā, he maha ngā wā kāore pea. Me tirotiro tonu te tipu i te hangarau o ngā SIF e pā ana ki te whakamātautau whakamātautau.
Me uru ki te whakamātautau whakamātautau he tirotiro i te tāutanga me te whakatikatika o te SIF ina hiahiatia kia tutuki ai te 61511-1, te Rārangi 16.3.2. Me whai tirotiro whakamutunga kia mōhio ai kei te tika ngā mea katoa, me te tirotiro anō kua whakahokia tika te SIF ki te ratonga tukatuka.
He mea nui te tuhi me te whakatinana i tētahi tikanga whakamātautau pai hei whakarite i te pono o te SIF puta noa i tōna oranga. Me whakarato e te tikanga whakamātautau ngā taipitopito e ranea ana hei whakarite kia mahi tonu, kia haumaru hoki ngā whakamātautau me te tuhi. Me utu ngā hapa morearea kāore i whakamatautauria e ngā whakamātautau taunakitanga kia mau tonu ai te pono o te haumaru o te SIF puta noa i tōna oranga.
Ko te tuhi i tētahi tikanga whakamātautau pai mō te whakamātautau whakamātautau he huarahi arorau ki te tātari hangarau o ngā hapa morearea pea, te whiriwhiri i ngā tikanga, me te tuhi i ngā mahi whakamātautau whakamātautau e tika ana mō ngā āheinga whakamātautau o te tipu. I a koe e mahi ana, me whiwhi tautoko mai ngā tipu i ngā taumata katoa mō te whakamātautau, me te whakangungu i ngā tohunga hangarau ki te mahi me te tuhi i te whakamātautau whakamātautau me te mārama hoki ki te hiranga o te whakamātautau. Tuhia ngā tohutohu me te mea ko koe te tohunga hangarau taputapu me mahi i te mahi, ā, ko te ora e whakawhirinaki ana ki te tika o te whakamātautau, nā te mea e mahi ana rātou.
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
E toru ngā wāhanga matua o te SIF, arā, ngā pūoko, ngā kaiwhakaoti arorau, me ngā wāhanga whakamutunga. He maha hoki ngā taputapu āwhina ka taea te hono atu ki roto i ia o ēnei wāhanga e toru (hei tauira, ngā ārai IS, ngā whakanui tūpono, ngā whakawhiti whakawhiti, ngā solenoid, me ētahi atu) me whakamātautau anō hoki.
Ngā whakamātautau ārai pūoko: Me whakarite te whakamātautau ārai pūoko kia taea e te pūoko te rongo i te taurangi tukanga puta noa i tōna whānuitanga katoa, ā, me tuku te tohu tika ki te kaiwhakaoti arorau SIS hei aromatawai. Ahakoa kāore i te whakaurua, ko ētahi o ngā mea hei whakaaro i te waihanga i te wāhanga pūoko o te tukanga whakamātautau ārai kei roto i te Ripanga 1.
Whakamātautau whakamātautau whakamātautau whakaoti rapanga: Ina oti te whakamātautau whakamātautau whakamātautau mahi-katoa, ka whakamatautauria te wāhanga o te kaiwhakaoti arorau ki te whakatutuki i te mahi haumaru a te SIF me ngā mahi e pā ana (hei tauira, ngā whakaoho, te tautuhi anō, ngā taha, te tātaritanga kaiwhakamahi, ngā hapa, te HMI, me ētahi atu). Me whakaoti e ngā whakamātautau whakamātautau mahi wāhanga, wāhanga rānei ēnei whakamātautau katoa hei wāhanga o ngā whakamātautau whakamātautau taupatupatu takitahi. Me whai te kaihanga whakaoti rapanga i tētahi tukanga whakamātautau whakamātautau kua tūtohutia i roto i te pukapuka haumaru taputapu. Ki te kore, ā, hei iti rawa, me huri te mana o te kaiwhakaoti arorau, ā, me tirohia ngā rēhita tātaritanga whakaoti rapanga, ngā rama tūnga, ngā ngaohiko tuku hiko, ngā hononga whakawhitiwhiti me te hapa. Me mahi ēnei tirotiro i mua i te whakamātautau whakamātautau mahi-katoa.
Kaua e whakaaro he pai tonu te pūmanawa mō ake tonu atu, ā, kāore e hiahiatia kia whakamatautauria te arorau i muri i te whakamātautau whakamātautau tuatahi, nā te mea ka taea e ngā huringa pūmanawa me ngā whakahoutanga taputapu kāore i tuhia, kāore i whakamanahia, kāore anō kia whakamatautauria te uru ki roto i ngā pūnaha i roto i te wā, ā, me whakauru ki roto i tō rapunga whakaaro whānui mō te whakamātautau whakamātautau. Me arotake te whakahaere i ngā huringa, te tiaki, me ngā rangitaki whakahou kia mōhio ai kei te hou tonu, ā, kei te tiakina tika, ā, ki te taea, me whakataurite te hōtaka tono ki te tārua hou.
Me āta whakamātau hoki i ngā mahi āwhina me ngā mahi tātaritanga katoa a te kaiwhakaoti arorau kaiwhakamahi (hei tauira, ngā kaitiaki, ngā hononga whakawhitiwhiti kōrero, ngā taputapu haumarutanga tukutuku, me ētahi atu).
Whakamātautau ārai huānga whakamutunga: Ko te nuinga o ngā huānga whakamutunga he takirere, heoi, ka whakamahia hoki ngā tīmatanga motuka taputapu hurihuri, ngā puku tere-rerekē me ētahi atu wāhanga hiko pēnei i ngā whakapā me ngā whati ara iahiko hei huānga whakamutunga, ā, me tātari me te whakamātau i ō rātou aratau rahunga.
Ko ngā momo rahunga matua mō ngā takirere ko te mau, te puhoi rawa, te tere rawa rānei o te wā urupare, me te turuturu, ā, ko ēnei katoa e pāngia ana e te atanga tukanga whakahaere o te takirere i te wā e whati ana. Ahakoa ko te whakamātautau i te takirere i ngā āhuatanga whakahaere te mea tino hiahiatia, ko te nuinga o ngā mahi he ātete ki te whati i te SIF i te wā e whakahaerehia ana te tipu. Ko te nuinga o ngā takirere SIS ka whakamatautauria i te wā e heke ana te tipu i te korenga o te pēhanga rerekētanga, koinei te mea tino iti rawa te uaua o ngā āhuatanga whakahaere. Me mōhio te kaiwhakamahi ki te pēhanga rerekētanga whakahaere kino rawa atu me ngā pānga whakahekenga takirere me te tukanga, me whai wāhi ki te hoahoa me te rahi o te takirere me te 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).
Ka pā anō hoki ngā pāmahana taiao ki ngā kawenga waku takirere, nō reira ko ngā takirere whakamātautau i te rangi mahana te nuinga o te wā ko te kawenga waku iti rawa te tono ina whakaritea ki te mahi i te rangi makariri. Nō reira, me whai whakaaro ki te whakamātautau taunakitanga o ngā takirere i te pāmahana ōrite hei whakarato raraunga ōrite mō te whakamātautau whakatau mō te whakatau i te hekenga o te mahi takirere.
Ko ngā takirere me ngā tūnga atamai, me te kaiwhakahaere takirere mamati rānei, he kaha ki te waihanga i tētahi waitohu takirere ka taea te whakamahi hei aroturuki i te hekenga o te mahi takirere. Ka taea te tono i tētahi waitohu takirere turanga hei wāhanga o tō ota hoko, ka taea rānei e koe te waihanga i tētahi i te wā o te whakamātautau whakamātautau tuatahi hei tūāpapa. Me mahi te waitohu takirere mō te whakatuwheratanga me te kati o te takirere. Me whakamahi hoki i te tātaritanga takirere matatau mēnā e wātea ana. Ka taea e tēnei te āwhina ki te kī atu ki a koe mēnā kei te heke te mahi a tō takirere mā te whakataurite i ngā waitohu takirere whakamātautau whakamātautau me ngā tātaritanga i muri mai ki tō tūāpapa. Ka taea e tēnei momo whakamātautau te āwhina ki te utu mō te kore whakamātautau i te takirere i ngā pēhanga mahi kino rawa atu.
Tērā pea ka taea hoki e te waitohu takirere i te wā o te whakamātautau whakamātautau te tuhi i te wā urupare me ngā tohu wā, ka kore e hiahiatia he wati mutu. Ko te pikinga o te wā urupare he tohu mō te hekenga o te takirere me te pikinga o te kawenga waku hei neke i te takirere. Ahakoa kāore he paerewa e pā ana ki ngā huringa o te wā urupare takirere, ko te tauira kino o ngā huringa mai i te whakamātautau whakamātautau ki te whakamātautau whakamātautau he tohu mō te ngaronga pea o te tawhē haumaru me te mahi a te takirere. Me whakauru he waitohu takirere ki roto i ngā whakamātautau ārai takirere SIS hou hei tikanga hangarau pai.
Me ine te pēhanga hau o te taputapu takirere i te wā o te whakamātautau whakamātautau. Ahakoa ko te puna takirere mō te takirere whakahoki-puna te mea e kati ana i te takirere, ko te kaha, ko te taipana rānei e pā ana ka whakatauhia e te nui o te pēhanga o te puna takirere e te pēhanga o te takirere (e ai ki te Ture a Hooke, F = kX). Mena he iti tō pēhanga tuku, kāore te puna e pēhi nui, nō reira ka iti ake te kaha e wātea ana hei neke i te takirere ina hiahiatia. Ahakoa kāore i roto, ko ētahi o ngā mea hei whakaaro i te hanga i te wāhanga takirere o te tukanga whakamātautau whakamātautau kei roto i te Ripanga 2.
Wā tuku: Whiringa-ā-rangi 13-2019