Umbhobho wentsimbi yekhabhoni we-Schedule 40 intshi ezi-6 unobunzima obuziikhilogram ezili-18.97 ngenyawo. Ubukhulu obufanayo kwiSchedule 80 bunobunzima obuziikhilogram ezingama-28.60 ngenyawo. Ukunyuka kobunzima obuziipesenti ezingama-50 okubangelwa lolu tshintsho loyilo kuya kunyusa iindleko zokuthumela ngamawaka eedola ngexesha lokwenziwa kweprojekthi enye. Umbhobho we-Schedule 40 intshi ezi-2 unobunzima obuziikhilogram ezili-3.65 kuphela, ngelixa umbhobho we-Schedule 40 intshi ezi-12 unobunzima obuziikhilogram ezili-53.52 ngenyawo.
Ubunzima bezinto zokufaka imibhobho buba yinto ebalulekileyo ngexesha loyilo lwemibhobho. Iinjineli zisebenzisa ubunzima ukumisela iindleko zokuthutha impahla, ukumisela iimfuno zekreyini, ukubala umgama wokuxhasa, kunye nokuqikelela iimfuno zobunzima besakhiwo. Uninzi lweenjineli lusaxhomekeke kwimemori yazo okanye kwiindlela ezisisiseko zokuqikelela ukubala ubunzima bemibhobho. Uqikelelo oludalwa ziinjineli ludla ngokuba nempazamo ye-10-20%, nto leyo ekhokelela ekugqithiseni kwebhajethi yokuthumela kunye nokunciphisa ubungakanani benkxaso yemibhobho.
Itshati epheleleyo yobunzima bepayipi yentsimbi yekhabhoni kunye nentsimbi engatyiwayo ikweli nqaku. Olu xwebhu lubonelela ngeetafile zobunzima ezibonisa ubungakanani obuqhelekileyo kunye neeshedyuli kunye nefomula yobunzima bepayipi equka umzekelo osebenzayo kunye nolwazi olusebenzayo malunga nendlela ubunzima obuchaphazela ngayo ukuthunyelwa kunye nokuphathwa kunye noyilo lwesakhiwo.
IItrakthi ezibalulekileyo
- Ubunzima bombhobho wentsimbi buyahluka ngokobukhulu obuqhelekileyo, ishedyuli, kunye nomgangatho wezinto ezisetyenzisiweyo. Itshati epheleleyo yobunzima bombhobho wentsimbi ibalulekile ukuze kuqikelelwe ngokuchanekileyo.
- Ifomula yobunzima bombhobho: W = 10.68 x (OD – Wall) x Udonga lunika i-lb/ft yombhobho wentsimbi yekhabhoni ngee-intshi.
- Umbhobho weShedyuli 80 unobunzima obumalunga nama-40-70% ngaphezu kweShedyuli 40 kwiNPS efanayo, nto leyo enyusa ngokuthe ngqo iindleko zokuthutha impahla kunye nokufakela.
- Umbhobho wentsimbi engatyiwayo unzima kancinci kunentsimbi yekhabhoni ngokwemilinganiselo efanayo kuba i-304 kunye ne-316 zinoxinano oluphezulu.
- Ukunyamezelana kwee-mill kuvumela ubukhulu bodonga ukuya kuthi ga kwi-12.5% ngaphantsi kwesiqhelo, ngoko ke ubunzima bokwenyani bokuthunyelwa bunokuba lula nge-5-10% kunexabiso leetshathi zethiyori.
Indlela Yokubala Ubunzima Bepayipi: Ifomula
Ngaphambi kokuba usebenzise itshati yobunzima bombhobho wentsimbi, kuyanceda ukuqonda apho amanani avela khona. Ubunzima bombhobho bubungakanani nje bentsimbi eludongeni lombhobho obuphindaphindwa bubuninzi bezinto.
Kwipayipi yentsimbi yekhabhoni, ifomula eqhelekileyo kwiiyunithi zobukhosi yile:
W = 10.68 x (OD – t) xt
Apho u-W ebunzima ngeepawundi ngenyawo, i-OD bububanzi bangaphandle ngee-intshi, kwaye u-t bubukhulu bodonga ngee-intshi. I-constant 10.68 idibanisa uxinano lwentsimbi (malunga ne-490 lb/ft³) kunye nezinto zokuguqula iyunithi.
Kwiiyunithi ze-metric, ifomula iba:
W = 0.02466 x (OD – t) xt
Apho u-W ebunzima ngeekhilogram ngemitha nganye, i-OD kunye no-t zikwiimilimitha, kwaye i-0.02466 ibandakanya ubuninzi bentsimbi (7,850 kg/m³).
Nantsi umzekelo osebenzayo we-NPS 4, iShedyuli 40:
- OD = 4.500 intshi
- Ubukhulu bodonga = 0.237 intshi
- W = 10.68 x (4.500 – 0.237) x 0.237
- W = 10.68 x 4.263 x 0.237
- W = 10.79 lb/ft
Oko kuhambelana nexabiso letafile eliqhelekileyo ngokuchanekileyo. Ungayisebenzisa le fomula xa itshati yobunzima bombhobho wentsimbi ingabonisi ubunzima bobukhulu obungengobuqhelekileyo okanye xa unobukhulu bodonga obulinganisiweyo obuvela kwisatifikethi sokugaya endaweni yexabiso eliqhelekileyo.
Ukuze ubone nzulu indlela esebenza ngayo imilinganiselo kunye neeshedyuli zepayipi, jonga isikhokelo sethu sentsingiselo yeshedyuli yepayipi.
Itshati yoBunzima bePipe yeNsimbi: Intsimbi yeCarbon (ASME B36.10M)
Itheyibhile engezantsi ibonisa ubunzima bethiyori ngenyawo nganye ngobukhulu beepayipi zentsimbi yekhabhoni ezichazwe rhoqo kunye neeshedyuli phantsi kwe -ASME B36.10M . La maxabiso acinga ukuba yipayipi engenanto enobukhulu bodonga obuqhelekileyo.
Ubunzima bePipe yeSteel yeCarbon yi-NPS kunye neShedyuli
| NPS | OD (ngaphakathi) | I-Sch 40 (lb/ft) | I-Sch 40 (kg/m) | I-Sch 80 (lb/ft) | I-Sch 80 (kg/m) | I-Sch 160 (lb/ft) | I-Sch 160 (kg/m) |
|---|---|---|---|---|---|---|---|
| 1 / 2 " | 0.840 | 0.85 | 1.27 | 1.09 | 1.62 | 1.31 | 1.95 |
| 3 / 4 " | 1.050 | 1.13 | 1.68 | 1.47 | 2.19 | 1.94 | 2.89 |
| 1 " | 1.315 | 1.68 | 2.50 | 2.17 | 3.23 | 2.84 | 4.23 |
| 1-1 / 2 ″ | 1.900 | 2.72 | 4.05 | 3.63 | 5.41 | 4.86 | 7.24 |
| 2 " | 2.375 | 3.65 | 5.44 | 5.02 | 7.48 | 7.46 | 11.11 |
| 3 " | 3.500 | 7.58 | 11.29 | 10.26 | 15.29 | 14.32 | 21.33 |
| 4 " | 4.500 | 10.79 | 16.07 | 14.99 | 22.33 | 22.51 | 33.54 |
| 6 " | 6.625 | 18.97 | 28.26 | 28.60 | 42.62 | 36.39 | 54.22 |
| 8 " | 8.625 | 28.55 | 42.55 | 43.43 | 64.71 | 67.76 | 100.94 |
| 10 " | 10.750 | 40.48 | 60.31 | 64.49 | 96.11 | 104.13 | 155.14 |
| 12 " | 12.750 | 53.52 | 79.73 | 88.71 | 132.15 | 143.68 | 214.08 |
Ezi zinzima zizinto ezisisiseko zepayipi engenanto. Ubunzima bokwenyani bokuthunyelwa bunokwahluka kancinci ngokuxhomekeke kwinqanaba elithile lezinto kunye nokunyamezela kokwenziwa.
Umahluko phakathi kobunzima beShedyuli 40 noweShedyuli 80
| NPS | Ubunzima beSch 40 | Ubunzima beSch 80 | Ukunyuka kobunzima |
|---|---|---|---|
| 2 " | 3.65 lb / ft | 5.02 lb / ft | 38% ubunzima |
| 4 " | 10.79 lb / ft | 14.99 lb / ft | 39% ubunzima |
| 6 " | 18.97 lb / ft | 28.60 lb / ft | 51% ubunzima |
| 8 " | 28.55 lb / ft | 43.43 lb / ft | 52% ubunzima |
| 12 " | 53.52 lb / ft | 88.71 lb / ft | 66% ubunzima |
Umsantsa wobunzima phakathi kweShedyuli 40 kunye neShedyuli 80 uyanda njengoko ubungakanani bombhobho obuqhelekileyo bukhula. Kwimbhobho encinci, umahluko ulawuleka. Kwimigca emikhulu, ubunzima obongezelelweyo bunokufuna iikhreyini ezinkulu, inkxaso enamandla, kunye nemithwalo ebiza kakhulu.
Itshati yobunzima bepayipi yentsimbi engatyiwayo
Itshati yobunzima beepayipi zentsimbi engagqwali ibonisa ubunzima bazo ngokweshedyuli ye-ASME B36.19, eyahlukileyo kwi-B36.10M ngobukhulu beepayipi ezinkulu. Ubunzima bentsimbi engagqwali budlula obo bentsimbi yekhabhoni ngobuninzi obuncinci. Ubunzima beGrade 304 bulinganisa i-495 lb/ft³ (7,930 kg/m³) ngelixa intsimbi yekhabhoni inobunzima be-490 lb/ft³ (7,850 kg/m³).
Ubunzima boMbhobho weNtsimbi engagqwaliyo obuyi-304 (Ishedyuli yama-40 kunye nama-80S)
| NPS | OD (ngaphakathi) | I-Sch 40S (lb/ft) | I-Sch 40S (kg/m) | I-Sch 80S (lb/ft) | I-Sch 80S (kg/m) |
|---|---|---|---|---|---|
| 1 / 2 " | 0.840 | 0.85 | 1.27 | 1.09 | 1.62 |
| 1 " | 1.315 | 1.68 | 2.50 | 2.17 | 3.23 |
| 2 " | 2.375 | 3.65 | 5.44 | 5.02 | 7.48 |
| 4 " | 4.500 | 10.79 | 16.07 | 14.99 | 22.33 |
| 6 " | 6.625 | 18.97 | 28.26 | 28.60 | 42.62 |
| 8 " | 8.625 | 28.55 | 42.55 | 43.43 | 64.71 |
| 12 " | 12.750 | 49.56 | 73.84 | 88.71 | 132.15 |
Ubukhulu bodonga lweShedyuli 40S kunye neShedyuli 40S ziyafana ngokulinganisa iimpawu zazo zobunzima kuzo zonke iipayipi ezinobukhulu obungaphantsi kwe-NPS 8. Kwi-NPS 12, iShedyuli 40S incinci kuneShedyuli 40 (0.375″ vs 0.406″), ngoko ke ubunzima bentsimbi engagqwaliyo buyehla bufike kwi-49.56 lb/ft xa kuthelekiswa ne-53.52 lb/ft yentsimbi yekhabhoni iShedyuli 40.
Kwiindawo ezinobungozi kakhulu apho kufuneka khona umbhobho wentsimbi engagqwaliyo , soloko uqinisekisa ukuba ishedyuli icwangcisiwe. Iishedyuli ze-B36.19 S-suffix azitshintshisani neeshedyuli ze-B36.10M ze-NPS 10 nangaphezulu.
Ubunzima bePipe kwizicelo zokwenyani
Idatha evela kwitshati yobunzima bepayipi yentsimbi ayisiyonombolo yesalathiso nje kuphela. Ichaphazela ngokuthe ngqo ukuthengwa, uthutho, ukufakwa, kunye nobunjineli besakhiwo kuyo yonke iprojekthi yemizi-mveliso.
Impembelelo yeendleko zokuthumela kunye nempahla
Indlela eqhelekileyo yokubeka amaxabiso kwimpahla yolwandle kwipayipi yentsimbi ifuna ukulinganiswa kobunzima bepayipi yentsimbi kwiitoni ze-metric. Ubunzima bomthwalo omnye, oqulethe iimitha ezingama-5,000 zepayipi yeShedyuli 40 eyi-intshi ezi-6, bufikelela kwiitoni ze-metric ezili-142. Ubude obufanayo kwiShedyuli 80 bunobunzima obumalunga neetoni ze-metric ezingama-214. Iindleko zomthwalo zangoku ezivela eTshayina ukuya eYurophu naseMbindi Mpuma ziphumela kwindleko eyongezelelweyo yokuthutha ukusuka kwi-4,000 ukuya kwi-8,000 ngenxa yomahluko wobunzima beetoni ezingama-72.
ULi Wei, osebenza njengomphathi wokuthenga kwinkampani yokwakha eseDubai, wafumanisa olu lwazi ngexesha lomsebenzi wakhe kwiprojekthi yemibhobho yamanzi abandayo ngo-2024. Ingcaciso yayifuna iShedyuli 80 kuyo yonke le projekthi ukuze ibonelele ngokhuseleko loomatshini. ULi Wei wafumana iikowuteshini zeShedyuli 40 kunye neShedyuli 80. Umahluko weendleko zezinto ezibonakalayo phakathi kwabo wahlala uphakathi. Umahluko weendleko zokuthumela wawungekho. Umbhobho weShedyuli 80 wawunobunzima obungaphezulu ngama-50%, nto leyo eyabangela ukuba ukuthunyelwa kungene kudidi lweendleko zokuthutha eziphezulu. Inkqubo yobunjineli bexabiso, awayiphumezayo, yonge ama-200 kwiindleko zokuthumela kwaye yehlisa iindleko zakhe zokuqeshisa iikreyini kwindawo ngokukhetha kwakhe amasebe angengomsebenzi ukuya kwiShedyuli 40. Olu tshintsho aluzange lube nefuthe kukhuseleko lwenkqubo kuba uxinzelelo lokusebenza lwalungaphantsi kakhulu kumthamo weShedyuli 40.
Uyilo loMthwalo weZakhiwo kunye neNkxaso
Ubunzima bombhobho bumisela isithuba sokuxhasa, imithwalo ye-ankile, kunye namandla e-seismic. Umgama weemitha ezili-100 wombhobho weShedyuli 40 oziisentimitha ezi-8 unobunzima obuziikhilogram ezingama-2,855. Umlinganiselo ofanayo kwiShedyuli 80 unobunzima obuziikhilogram ezingama-4,343. Loo mitha eyongezelelweyo eyi-1,488 ifuna:
- Inkxaso yombhobho eqinileyo xa ikufutshane
- Iibholithi ezinkulu ze-anchor kunye neepleyiti zesiseko
- Isinyithi esongezelelweyo kwisakhelo sesakhiwo
- Umthamo ophezulu wokuxhasa inyikima
Kwiindawo zenyikima, ukubaluleka kobunzima kuyaphindaphindwa. Amandla enyikima alingana nobunzima. Umbhobho onzima ngama-50% udala amandla aphezulu asecaleni angama-50% ngexesha lenyikima. Ngamanye amaxesha iinjineli zichaza iShedyuli 40 ngaphezu kweShedyuli 80 kwimigca engengomqobo ngokukodwa ukunciphisa imithwalo yenyikima kwisakhiwo.
Umsebenzi woLawulo kunye noFakelo
Inkqubo yokufakela ifuna izixhobo ezongezelelweyo kunye nabasebenzi abongezelelweyo bokuphatha iipayipi ezinzima. Ubunzima bombhobho weShedyuli 40 oyi-intshi ezili-12 bulingana neepawundi ezingama-53.5 ngenyawo nganye yobude bawo. Ubunzima bombhobho omnye oziimitha ezingama-20 bulingana neepawundi ezili-1,070. Ubukhulu bokuphakamisa loo nto bufuna abantu ababini ukuyiphatha. Ubungakanani obufanayo kwiShedyuli 160 bulingana neepawundi ezili-143.7. Ubunzima bombhobho oziimitha ezingama-20 bulingana neepawundi ezingama-2,874. Inkqubo yokufakela ifuna i-forklift okanye i-crane kwijoyinti nganye.
Inkqubo yokufaka iza kuba nokulibaziseka ngenxa yokwahluka kwezinto ezimbini ezahlukeneyo. Abasebenzi banokuhambisa iipayipi ezikhaphukhaphu ngokulula kuba abadingi zixhobo zikhethekileyo. Inkqubo yokufaka ifuna abasebenzi basebenzise izixhobo zokubopha kuba iipayipi ezinzima zifuna ukuphathwa ngendlela ekhethekileyo.
Ukuze ufumane isikhokelo sokukhetha ishedyuli efanelekileyo yobunzima bakho kunye neemfuno zoxinzelelo, jonga isikhokelo sethu sovavanyo loxinzelelo lwepayipi lweShedyuli 40.
Iziqinisekiso zokunyamezela ubunzima bepayipi kunye nokugaya
Umahluko wobunzima phakathi kweetshathi zobunzima beepayipi zentsimbi kunye nobunzima bokuthunyelwa bokwenyani buvela kwiindlela zokuthwala ezisetyenziswayo. I-ASTM A53 kunye ne-ASTM A106 zivumela ubukhulu bodonga ukuba bube buncinci nge-12.5% kunexabiso eliqhelekileyo. Ipayipi yeShedyuli 40 ivumela udonga oluqhelekileyo oluyi-intshi eziyi-0.237 ukuba lulinganise buncinci njenge-intshi eziyi-0.207.
Ubukhulu bodonga lombhobho bumisela ubunzima bawo kuba ubunzima bombhobho buhambelana ngqo nobukhulu bodonga. Udonga oluncinci oluyi-12.5% luthetha ukuba umbhobho uqulethe izinto zentsimbi ezingaphantsi nge-12.5%. Umahluko wobunzima obupheleleyo kwimpahla enkulu uya kufikelela kumanqanaba abalulekileyo.
Kukho izatifikethi zovavanyo lwe-mill ukuqinisekisa umgangatho wemveliso. I-MTR ilandelela imilinganiselo yobukhulu bodonga kunye nokubala ubunzima obusebenza kwindawo ethile yobushushu. Uqikelelo lwakho lokuthumela luya kubangela ukuba ubunzima buqikelelwe ngaphezulu kwe-5-10% ukuba usebenzisa amaxabiso etshathi yethiyori. Ubunzima bethiyori bubonelela ngokhetho olukhuselekileyo kwiinjongo zohlahlo-lwabiwo mali lwempahla. Ubunzima bokwenyani besatifikethi se-mill kufuneka busetyenziselwe ukubala ngokuchanekileyo ulwakhiwo.
Ubunzima obuqhelekileyo bumele enye yeempawu zepayipi eziqhelekileyo. Istencil ibonisa ubunzima obuqhelekileyo be-18.97 LB/FT ngokusebenzisa uphawu lwe-NPS 6 SCH 40 18.97 LB/FT. I-MTR inika ulwazi lokwenyani lobunzima, ngelixa unokulinganisa ubude besampulu usebenzisa isikali esiqinisekisiweyo.
Imibuzo Ebuzwa Rhoqo Malunga Nobunzima Bepayipi
Ingakanani ubunzima bombhobho weShedyuli 40?
Ubunzima bombhobho weShedyuli 40 buxhomekeke kubukhulu bawo obuqhelekileyo ngokweetshathi zobunzima bombhobho wentsimbi. Ubunzima bombhobho weShedyuli 40 oyi-intshi ezi-2 bufikelela kwiipawundi ezi-3.65 ngenyawo. Ubunzima bombhobho we-intshi ezi-4 bufikelela kwiipawundi ezili-10.79 ngenyawo. Ubunzima bombhobho we-intshi ezi-6 bufikelela kwiipawundi ezili-18.97 ngenyawo. Ubunzima bombhobho we-intshi ezi-8 bufikelela kwiipawundi ezingama-28.55 ngenyawo. Itshathi yobunzima bombhobho wentsimbi inika ulwazi olupheleleyo lobunzima kuzo zonke iipayipi ezisetyenzisiweyo kweli nqaku.
Ithini ifomula yokubala ubunzima bombhobho?
Ifomula u-W = 10.68 x (OD – t) xt ibala ubunzima bombhobho wentsimbi yekhabhoni kwiiyunithi zobukhosi. Ifomula isebenzisa u-W njengobunzima kwi-lb/ft kunye ne-OD njengobubanzi bangaphandle kwii-intshi kunye no-t njengobukhulu bodonga kwii-intshi. Ifomula ye-metric u-W = 0.02466 x (OD – t) xt ibala ubunzima kwi-kg/m kusetyenziswa ubukhulu be-millimeter.
Ingakanani ubunzima bombhobho wentsimbi oyi-intshi ezi-6?
Ubunzima bombhobho wentsimbi yekhabhoni weShedyuli 40 ngobukhulu bombhobho obuziisentimitha ezi-6 bufikelela kwi-18.97 lb/ft (28.26 kg/m). Ubungakanani obufanayo kwiShedyuli 80 bubunzima obuyi-28.60 lb/ft (42.62 kg/m). Ubunzima bentsimbi engatyiwayo yeShedyuli 40S bulingana nobunzima bentsimbi yekhabhoni yeShedyuli 40 kolu bukhulu.
Ingaba umbhobho wentsimbi engagqwaliyo unzima kunombhobho wentsimbi yekhabhoni?
Impendulo ithi ewe kuba intsimbi engatyiwayo ye-304 inobunzima obukhulu kunentsimbi yekhabhoni. Intsimbi engatyiwayo yebanga le-304 inobunzima obumalunga ne-495 lb/ft³ xa ithelekiswa ne-490 lb/ft³ yentsimbi yekhabhoni. Kwiimilinganiselo ezifanayo, ipayipi yentsimbi engatyiwayo ye-304 inobunzima obumalunga ne-1% ngaphezu kombhobho wentsimbi yekhabhoni. Iintsimbi ze-NPS 8 kunye nezingaphantsi kwemibhobho kufuneka ziphathwe njengobunzima obulinganayo ngokwezicelo ezininzi ezisebenzayo.
Yintoni umahluko phakathi kobunzima phakathi kweShedyuli 40 kunye neShedyuli 80?
Umbhobho weShedyuli 80 unobunzima obuyi-40-66% ngaphezu koweShedyuli 40, kuxhomekeke kubukhulu obuqhelekileyo. Umahluko mncinci kumbhobho omncinci (38% kwi-NPS 2) kwaye mkhulu kumbhobho omkhulu (66% kwi-NPS 12). Ukonyuka kobunzima kuchaphazela ngokuthe ngqo iindawo ezintathu, eziquka iindleko zokuthumela, uyilo lwenkqubo yokuxhasa kunye neemfuno zabasebenzi bokufakela.
isiphelo
Isigaba ngasinye seprojekthi yepayipi sifuna ubunzima bepayipi njengenkcazo esisiseko. Itshati yobunzima bepayipi yentsimbi kweli nqaku ikunika amaxabiso ethiyori epayipi yekhabhoni kunye nentsimbi engatyiwayo kuzo zonke iishedyuli kunye nobukhulu obuqhelekileyo. Ifomula yobunzima bepayipi ikunceda ukubala ubungakanani obungengomgangatho kwaye uqinisekise amaxabiso etafile.
Ubunzima bethiyori bukhona kuphela njengeengcamango zethiyori. Ubunzima bokwenyani bento buya kutshintsha phakathi kwe-5 kunye ne-10 ekhulwini ngenxa yokunyamezelana kokwenziwa, ukutshintsha koxinano lwezinto, kunye nokulungiselela ukuphela. Sebenzisa amaxabiso etshathi kuqikelelo lwempahla. Izatifikethi zovavanyo lwe-mill kufuneka zisetyenziswe ukwenza izibalo ezichanekileyo zesakhiwo.
Ukukhetha phakathi kweShedyuli 40 kunye neShedyuli 80 akusosigqibo soxinzelelo nje kuphela. Isigqibo sifuna ukubalwa kobunzima obuya kuchaphazela iindleko zokuthumela kunye neendleko zokuphatha kunye nokuxhasa iindleko zoyilo kunye nokufakela. IShedyuli 40 iyahlangabezana neemfuno zoxinzelelo kwizicelo ezininzi ngelixa ibonelela ngobunzima obuphantsi kunye neenzuzo zeendleko.
Cela isicatshulwa sentsimbi yekhabhoni okanye ipayipi yentsimbi engatyiwayo kunye nedatha yobunzima echanekileyo yokuthumela kwakho kunye nokubala ulwakhiwo. I-LIANYUNGANG DAPU METAL CO., LTD ibonelela ngobukhulu bepayipi obuqhelekileyo nobungokwezifiso kunye neziqinisekiso ezipheleleyo ze-mill, amaxwebhu ethiyori kunye nobunzima bokwenyani, kunye nokuhanjiswa kwihlabathi liphela kwindawo yakho yeprojekthi.
