Ta Yaya Tsarin PLC da DCS Ke Ƙarfafa Ayyukan Ma'adinai Masu Hankali?
Daga hakowa a ƙarƙashin ƙasa zuwa sarrafa ma'adinai a saman ƙasa, ayyukan ma'adinai na zamani suna dogara ne da daidaitaccen kulawa na ainihin-lokaci ga na’urori masu rikitarwa. A zuciyar wannan ci gaban fasaha akwai Programmable Logic Controllers (PLCs) da Distributed Control Systems (DCS). Waɗannan dandamali suna ba injiniyoyi damar sarrafa muhimman matakai ta atomatik, sa ido kan lafiyar na’urori, kuma su amsa nan take ga canje-canjen yanayi. Ga manajojin shuka da injiniyoyin aikin atomatik, fahimtar ƙwarewar fasaha da dabarun haɗa waɗannan tsarin abu ne mai muhimmanci don ƙara lokacin aiki ba tare da tsayawa ba da tabbatar da tsaron aiki.
PLC da DCS: Zaɓen Tsarin Kulawa da Ya Fi Dacewa
Ɗaya daga cikin muhimman shawara a aikin sarrafa ma'adinai ta atomatik shi ne zaɓin tsarin da ya fi karkata kan PLC ko wanda ya fi karkata kan DCS. PLCs suna da ƙwarewa a aikace-aikacen kulawa masu sauri da na na’urori na kashi-kashi (discrete control). Suna da kyau wajen sarrafa injin murkushe dutse guda, bel ɗin ɗaukar kaya, ko tashar famfo ɗaya, tare da lokacin bincike (scan time) da ake auna shi da milisekan. Shirye-shiryensu suna bin ma’aunin IEC 61131-3, galibi ta amfani da Ladder Logic ko Structured Text, wanda yawancin injiniyoyin kulawa za su iya amfani da shi cikin sauƙi. A gefe guda, DCS an ƙera shi ne don sarrafa tsarin aiki a dukkan shuka. Yana bayar da maimaituwa (redundancy) a ciki, ɗakunan karfafa sarrafa tsari (advanced process optimization libraries), da kuma sarrafa bayanai cikin sauƙi ta hanyar bayanai (database). A babban masana’antar sarrafa ma’adanai, DCS na iya daidaita PLC da dama, yana sarrafa setpoint, ƙararrawa, da tattara bayanan tarihi. Fahimtar fasaha a nan shi ne cewa tsarin haɗa duka biyun (hybrid architectures) suna ƙara yawaita: injiniyoyi yanzu suna girka PLC masu saurin aiki don sarrafa injuna kai tsaye, suna haɗa su da DCS don kulawa ta sama (supervisory), ta haka suna haɗa abin da ya fi kyau daga bangarorin biyu.
Fahimtar Zagayen Scan da Ƙuntatawar Ainihin-Lokaci
Ga injiniyoyin da ke shirya wa waɗannan tsarin, zagayen scan muhimmin ra’ayi ne. PLC na aiwatar da zagaye mai matakai uku: karanta sigogin shigarwa, aiwatar da shirin mai amfani, sannan sabunta sigogin fitarwa. Jimillar lokacin scan ne ke ƙayyade yadda tsarin zai iya amsawa da sauri. A aikace-aikacen ma’adinai kamar kulle-kullen belt ɗin ɗaukar kaya (conveyor interlocking), jinkirin zagayen scan na iya haifar da gazawar dakatar da bel na ƙarshe kafin kayan su taru su zubo. Saboda haka, lokacin da ake zaɓen na’urar sarrafawa, injiniyoyi dole su ƙididdige lokacin amsawa da ake buƙata. Don aikace-aikacen da ke da saurin gaske kamar na’urar daidaita saurin juyawar mota (variable frequency drives) a kan injin nika, ana yawan buƙatar scan ƙasa da milisekan 10. Masu sarrafawa na zamani suna iya wannan cikin sauƙi, amma irin salon shiryawa yana da tasiri: guje wa subroutine masu yin rikitarwa ba dole ba, da yin amfani da umarnin I/O na gaggawa ne kawai idan ana bukata, na taimakawa wajen kiyaye aiki mai tabbataccen lokaci (deterministic performance).
Binciken Fasaha Cikin Zurfi: Kula da Conveyor tare da Hada PLC da VFD
Ka ɗauki dogon tsarin bel ɗin ɗaukar ma’adinai daga ma’adinai zuwa shukar sarrafawa. Daga bangaren fasaha, wannan ba kawai aikin farawa-da-tsayawa ba ne. Injininyoyi dole su tsara tsarin farawa a hankali (soft-start) don rage ɗawon injina. Wannan yana haɗa haɗa PLC da Variable Frequency Drives (VFDs) ta amfani da ka’idojin sadarwa kamar Profibus ko EtherNet/IP. PLC na aika sigar nuni da sauri zuwa VFD kuma yana karɓar bayanin dawowa kan ƙarfi, juyi (torque), da matsalar kuskure. Don hana bel ya lalace yayin farawa, lissafin PLC na iya aiwatar da bayanin hanzari na lanƙwasan S-curve, yana ƙara sauri a hankali cikin sakan 60. Bugu da ƙari, tsarin dole ne ya sa ido kan zamewar bel ta amfani da na’urorin auna gudu: idan ƙafafun tuƙi na juyawa amma bel ɗin baya motsi, PLC dole ne ta bayar da umarnin tsayawa gaggawa cikin milisekan 200 don hana tashin wuta. Tsarin da aka tsara da kyau a wani ma’adinan platinum na Afirka ta Kudu da ya yi amfani da wannan hanyar ya rage yawan gazawar haɗin bel da 35% kuma ya ƙara tsawon rayuwar lanƙwasa wayoyin motoci (motor winding) da 20% saboda rage zafin da ke gajiya da su.
Dabarun Maimaituwa (Redundancy) ga Aikace-aikacen da Ba Za su Ƙyale Gazawa ba
A aikace-aikacen da suka da matuƙar muhimmanci kamar fitar da ruwa daga ma’adinai (mine dewatering) ko ɗagawa (hoisting), gazawar tsarin ba zaɓi ba ce. Injininyoyi suna aiwatar da maimaituwa a matakai daban-daban. Mafi yawan hanyar ita ce maimaituwar kayan aiki (hardware redundancy), inda CPUs biyu na PLC ɗaya iri suna aiki a layi ɗaya. Idan CPU ta farko ta gano kuskure (kamar matsalar ƙwaƙwalwa ko batirin wutar lantarki), na’urar ajiya (standby) na ɗaukar iko ba tare da katse aikin tsari ba. Wannan canjin ba tare da jijjiga tsari ba (bumpless transfer) yana buƙatar daidaita sadarwar backplane da daidaita jadawalin bayanai. A matakin hanyar sadarwa, tsarukan zobe (ring topologies) da ka’idoji kamar MRP (Media Redundancy Protocol) suna tabbatar da cewa karyewar igiya guda ɗaya ba ta ware na’urorin filin (field devices) ba. A wani shigarwa kwanan nan a ma’adinan potash na Kanada, daidaitaccen tsarin PLC mai maimaituwa ya hana fiye da sa’o’i 40 na yuwuwar tsayawar aiki a shekara ta hanyar yin canji ta atomatik lokacin da aka sami girgizar wutar lantarki, matsala da ake yawan samu a wuraren ma’adinai masu nisa.
Shirye-shirye Don Tsaro: Tsarin Rufe Gaggawa
Wani Safety Instrumented System (SIS) mai zaman kansa sau da yawa yana aiki ne a layi ɗaya da PLC na al’ada. Yayin da PLC na al’ada ke kula da samarwa, PLC na tsaro (mai darajar SIL 2 ko SIL 3) na sa ido kan yanayin gaggawa da kansa. Waɗannan PLC na tsaro suna amfani da tsarin lissafi na musamman, da aka tabbatar, da nau’ukan masu sarrafawa (processors) daban-daban don tabbatar da cewa gazawar sashi guda ba ta hana aikin tsaro ba. Misali, a wurin sel ɗin flotation, idan PLC na al’ada ta gaza kuma ta rasa sadarwa, PLC na tsaro zai gano wannan ta hanyar agogon sintiri (watchdog timer) kuma ta atomatik ya fara yanayin tsaro, kamar rufe bawul ɗin warewa da yanke wuta ga injin masu jujjuyawa (agitators). Shiryawa wa waɗannan tsarin yana buƙatar bin ka’idoji kamar IEC 61511, kuma injiniyoyi dole ne su yi gwajin tabbatarwa lokaci zuwa lokaci don tabbatar da cewa ayyukan tsaro na aiki. Wannan tsarin matakai masu yawa yana tabbatar da cewa ko da yake atomatik na ƙara yawan samarwa, ba ya taɓa sadaukar da tsaron ma’aikata.
Haɗa Bayanai: Daga PLC zuwa Cloud da Dandamalin Nazari
Ma’adinai na zamani wurin ne mai yalwar bayanai, kuma PLCs sune babban tushe. Bayan sarrafa sauƙaƙan I/O, injiniyoyi yanzu suna sa PLCs su rika tura bayanai zuwa masu adana tarihi (historians) da dandamalin cloud. Wannan yana buƙatar saita sabar OPC UA waɗanda ke tattara bayanai daga masu sarrafawa da yawa su gabatar da su cikin tsari guda ga tsarin mataki na sama. Misali, bayanan girgiza daga ɗaukar nauyin injin murkushe dutse, da PLC ta tattara ta hanyar samfurin shigarwar analog, za a iya turawa zuwa ƙa’idar kula da gyaran gaggawa (predictive maintenance algorithm) a cikin cloud. Idan ƙa’idar ta gano wani tsarin da ke gabaci gazawa, tana haifar da umarnin aikin gyara ta atomatik a cikin CMMS (Computerized Maintenance Management System). A wani ma’adinan zinariya a Nevada, wannan haɗin bayanai ya rage tsayawar aiki ba tare da shiri ba da 27% a shekara ta farko. Kalubalen fasaha a nan shi ne sarrafa cunkoson hanyar sadarwa (bandwidth) da tabbatar da daidaiton lokutan rajistar bayanai (timestamp) a duk masu sarrafawa da aka rarraba, wanda sau da yawa ke buƙatar sabar lokaci masu daidaita lokaci ta GPS a hanyar sadarwar kulawa.
Misalin Aikace-aikace: Samfuri Ta Atomatik da Bincike a Masana’antar Sarrafawa
A cikin shukar sarrafa ma’adinai, kula da ingancin ma’adinan da ake ciyarwa daidaitacce aiki ne mai wahala. Wani babban kamfanin sarrafa tagulla-molybdenum ya aiwatar da tashar ɗaukar samfurin da PLC ke sarrafawa a bakin injin nika. Kowane mintuna 15, PLC tana motsa na’urar ɗaukar samfurin da iska (pneumatic sampler) don ɗebo samfurin. Sannan ta sarrafa bel ɗin ɗaukar kaya don kai samfurin zuwa na’urar nazarin XRF. PLC ta karanta sakamakon na’urar sannan ta tura shi zuwa DCS, wanda ya daidaita saitin girman nika (grind size setpoints) a kan injin SAG ta atomatik. Wannan kulawar madauki rufaffe, da aka aiwatar gaba ɗaya ta hanyar atomatik, ta kiyaye ingantacciyar nika duk da sauyin taurin ma’adinai. A cikin watanni 12, shukar ta rubuta ƙaruwa da 6.2% a yawan kayan da ake wucewa da kuma raguwa da 10% a lalacewar layin kariya (liner wear), wanda aka danganta kai tsaye da daidaitattun canje-canjen ainihin-lokaci da tsarin ɗaukar samfurin da PLC ke jagoranta ya bai wa damar yi.
Mafi Kyawun Hanyoyin Shigarwa: Kula da Sigina da Ƙasa (Grounding)
Ga injiniyoyin filin, ingancin shigarwa ne ke ƙayyade dogon lokacin amincin aiki. Sigogin analog daga na’urar auna matsin lamba ko ma’aunin kwarara (flow meters) suna da sauƙin kamuwa da hayaniyar lantarki, musamman a muhalli irin na ma’adinai da manyan motoci ke yawan farawa da tsayawa. Ya kamata a shigar da signal isolators tsakanin na’urar filin da samfurin shigarwar PLC don karya zagayowar ƙasa (ground loops). Bugu da ƙari, yin ƙasa daidai abu ne da ba a yi sassauci a kai ba. Dole ne kwandon kulawa su sami sandar ƙasa guda (single-point ground bus), kuma ƙasan murfin igiyoyin na’urorin auna (instrumentation cable shields) su kasance a haɗe a gefe guda kawai don hana yawo na ƙarar lantarki. Lokacin haɗa shigarwar dijital, injiniyoyi yakamata su yi amfani da na’urorin hana tartsatsi (surge suppressors) a kan solenoids da relays don hana billa voltaji ta lalata samfurin fitarwar PLC. Bin waɗannan ka’idoji a sabon tashar jirgin ruwan karfen ƙarfe (iron ore port facility) ya haifar da raguwa da 98% a kurakuran I/O da ba a san dalili ba a shekara ta farko idan aka kwatanta da shigarwar da ta gabata da ba ta da irin wannan tsattsauran matakin kula da sigina.
Tambayoyi da Ake Yawan Yi
1. Menene lokacin scan da aka saba buƙata don kulle-kullen bel ɗin ɗaukar ma’adinai?
Domin samun tabbataccen kulle-kullen bel ɗin ɗaukar kaya, ya dace lokacin scan ya kasance ƙasa da milisekan 50, inda aikace-aikacen gaggawa kamar gano zamewar bel ke buƙatar scan a ƙasa da milisekan 20 don tabbatar da tsayawar gaggawa cikin sauri da hana lalacewa.
2. Ta yaya injiniyoyi ke sarrafa sadarwa tsakanin PLCs na masana’antun daban-daban?
Injiniyoyi galibi suna amfani da OPC UA (Open Platform Communications Unified Architecture) a matsayin ma’aunin sadarwa mai zaman kansa daga mai ƙera. Wannan na ba da damar PLC na Siemens ya rika musayar bayanai da PLC na Rockwell cikin sauƙi, yana ba da damar sarrafa hadadden kayan aiki daga masana’antun daban-daban.
3. Wace darajar SIL ake yawan buƙata don PLC na tsaron ma’adinai?
Mafi yawan aikace-aikacen tsaro a ma’adinai, kamar tsayawar gaggawa da sa ido kan iskar gas, suna buƙatar masu sarrafawa da ke da Safety Integrity Level (SIL) 2 ko SIL 3, gwargwadon kimar haɗari. Waɗannan masu sarrafawa suna amfani da kayan aiki da software da aka tabbatar don tabbatar da ingantaccen aiki lokacin da aka sami kuskure.
