Ngokuphathelele amaqondo obushushu avumelekileyo okusebenza ixesha elide kwii-cable cores, i-rubber insulation idla ngokulinganiswa kwi-65°C, i-polyvinyl chloride (PVC) insulation kwi-70°C, kunye ne-cross-linked polyethylene (XLPE) insulation kwi-90°C. Kwi-short-circuits (enexesha elide elingadluli kwimizuzwana emi-5), amaqondo obushushu aphezulu avumelekileyo yi-160°C kwi-PVC insulation kunye ne-250°C kwi-XLPE insulation.
I. Umahluko phakathi kweeCables ze-XLPE kunye neeCables ze-PVC
1. Iintambo ze-Low Voltage Cross-Linked (XLPE), ukusukela ekuqaleni kwazo phakathi kweminyaka yoo-1990, ziye zabonakala ziphucuka ngokukhawuleza, ngoku zithatha isiqingatha semarike kunye neentambo zePolyvinyl Chloride (PVC). Xa kuthelekiswa neentambo zePVC, iintambo zeXLPE zibonisa amandla aphezulu okuthwala umbane, amandla okugqithisa aqinileyo, kunye nexesha elide lokuphila (ixesha lokuphila kobushushu bentambo yePVC ngokuqhelekileyo liyiminyaka engama-20 phantsi kweemeko ezilungileyo, ngelixa ixesha lokuphila kwentambo yeXLPE ngokuqhelekileyo liyiminyaka engama-40). Xa kutsha, iPVC ikhupha umsi omnyama omninzi kunye neegesi ezinobuthi, ngelixa ukutsha kweXLPE kungavelisi iigesi zehalogen ezinobuthi. Ukuphakama kweentambo ezidibeneyo kuqatshelwa ngakumbi ngamacandelo oyilo kunye nesicelo.
2. Iintambo zePVC eziqhelekileyo (ukufakwa kwe-insulation kunye ne-sheath) zitsha ngokukhawuleza xa kutsha ngokukhawuleza, nto leyo ebangela imililo eyoyikekayo. Zilahlekelwa ngamandla okubonelela ngombane kwimizuzu e-1 ukuya kweyesi-2. Ukutsha kwePVC kukhupha umsi omnyama ongqindilili, nto leyo ekhokelela kwiingxaki zokuphefumla kunye nemingeni yokukhupha umoya. Okubaluleke ngakumbi kukuba, ukutsha kwePVC kukhupha iigesi ezinobuthi nezirhabaxa ezifana ne-hydrogen chloride (HCl) kunye ne-dioxins, ezizezona zizathu ziphambili zokufa kwimililo (ezibangela i-80% yokufa okunxulumene nomlilo). Ezi gesi zirhabaxa kwizixhobo zombane, zibeka emngciphekweni ukusebenza kwe-insulation kwaye zikhokelela kwiingozi zesibini ezinzima ukuzithintela.
II. Iintambo Ezingatshisi Ilangatye
1. Iintambo ezithintela umlilo kufuneka zibonise iimpawu ezithintela umlilo kwaye zahlulwe zibe ngamanqanaba amathathu athintela umlilo A, B, kunye no-C ngokwe-IEC 60332-3-24 “Uvavanyo kwiintambo zombane phantsi kweemeko zomlilo.” Udidi A lubonelela ngokusebenza okuphezulu okuthintela umlilo.
Uvavanyo lokutsha oluthelekiswayo kwiintambo ezithintela umlilo kunye nezithintela umlilo lwenziwe yi-US Standards and Technology Research Institute. Ezi ziphumo zilandelayo zibonisa ukubaluleka kokusebenzisa iintambo ezithintela umlilo:
a. Iingcingo ezithintela umlilo zibonelela ngexesha lokuphuma elingaphezulu ngokuphindwe kalishumi elinesihlanu xa kuthelekiswa neengcingo ezingathinteli umlilo.
b. Iingcingo ezithintela ilangatye zitshisa isiqingatha sezinto ezisetyenziswayo kuneengcingo ezithintela ilangatye.
c. Iingcingo ezithintela ilangatye zibonisa izinga lokukhululwa kobushushu ikota kuphela kweyongcingo ezithintela ilangatye.
d. Ukukhutshwa kwegesi enobuthi ngenxa yokutsha kuyinxalenye yesithathu kuphela yezo zinto zikhutshwayo kwiimveliso ezingabangeli mlilo.
e. Ukusebenza kokuvelisa umsi akubonisi mahluko mkhulu phakathi kweemveliso ezithintela ilangatye nezingathinteli ilangatye.
2. Iintambo ezingenayo iHalogen ezikhupha umsi omncinci
Iintambo ezingenamsi uphantsi ezingenayo i-halogen kufuneka zibe neempawu ezingenayo i-halogen, ezingatshisi uphantsi, kwaye zingatshisi ilangabi, kunye nezi nkcukacha zilandelayo:
I-IEC 60754 (uvavanyo olungenazo iihalogen) I-IEC 61034 (uvavanyo olusebenzisa umsi omncinci)
Ukuhanjiswa kombane okulinganisiweyo nge-PH Ukuhanjiswa kokukhanya okuncinci
PH≥4.3 r≤10us/mm T≥60%
3. Iintambo Ezingatshiyo
a. Izalathi zovavanyo lokutsha kwentambo ezingatshiyo (ubushushu bomlilo kunye nexesha) ngokwemigangatho ye-IEC 331-1970 zii-750°C iiyure ezi-3. Ngokwedrafti entsha yamva nje ye-IEC 60331 evela kwivoti yakutshanje ye-IEC, ubushushu bomlilo buqala kwi-750°C ukuya kwi-800°C iiyure ezi-3.
b. Iintambo kunye neentambo ezingatshiyo zinokwahlulwahlulwa zibe ziintambo ezingatshiyo ezimelana nomlilo kunye neentambo ezingatshiyo ezimelana nomlilo ngokusekelwe kumahluko kwizinto ezingezizo zesinyithi. Iintambo ezingatshiyo zasekhaya zisebenzisa ikakhulu ii-conductors ezine-mica kunye ne-extruded flame-insulation njengesakhiwo sazo esiphambili, uninzi lwazo ziimveliso zeClass B. Ezo zihlangabezana nemigangatho yeClass A zihlala zisebenzisa ii-synthetic mica tapes ezikhethekileyo kunye ne-mineral insulation (i-copper core, i-copper sleeve, i-magnesium oxide insulation, eyaziwa ngokuba yi-MI) iintambo ezingatshiyo.
Iintambo ezimelana nomlilo ezifakwe kwiminerali azitshi, azivelisi msi, azinamhlwa, azinatyhefu, azinampembelelo, kwaye ziyamelana nokutshizwa ngamanzi. Zaziwa njengeentambo ezimelana nomlilo, zibonisa ukusebenza okubalaseleyo kokuthintela umlilo phakathi kweentlobo zeentambo ezimelana nomlilo. Nangona kunjalo, inkqubo yazo yokuvelisa iyinkimbinkimbi, ixabiso lazo liphezulu, ubude bemveliso yazo bulinganiselwe, irediyasi yazo yokugoba inkulu, ubushushu bazo buchaphazeleka lula kukufuma, kwaye okwangoku, kuphela iimveliso ezingundoqo omnye ezingama-25mm2 nangaphezulu ezinokubonelelwa. Iiterminal ezisisigxina kunye nezihlanganisi eziphakathi ziyafuneka, okwenza ukufakwa nokwakhiwa kube nzima ngakumbi.
Ixesha lokuthumela: Sep-07-2023