1. Chidule chachitsulo cha cryogenic
1) Zofunikira zaukadaulo zazitsulo zotsika kutentha ndizo: mphamvu zokwanira komanso kulimba kokwanira m'malo otsika kutentha, ntchito yabwino yowotcherera, magwiridwe antchito komanso kukana dzimbiri, etc. Pakati pawo, kulimba kwa kutentha kochepa, ndiko kuti, luso. kuteteza kuchitika ndi kufalikira kwa brittle fracture pa kutentha kochepa ndi chinthu chofunika kwambiri. Choncho, maiko nthawi zambiri amatchula mtengo wa kuuma kwa kutentha kotsika kwambiri.
2) Pakati pa zigawo za otsika kutentha zitsulo, ambiri amakhulupirira kuti zinthu monga carbon, pakachitsulo, phosphorous, sulfure, ndi nayitrogeni kuwonongeka otsika kutentha toughness, ndi phosphorous ndi zoipa kwambiri, kotero oyambirira otsika kutentha dephosphorization ayenera kukhala. kuchitidwa pa smelting. Zinthu monga manganese ndi faifi tambala zimatha kusintha kutentha kutsika. Pachiwonjezeko chilichonse cha 1% cha nickel, kutentha kwanthawi yayitali kumatha kuchepetsedwa ndi 20°C.
3) Njira yochizira kutentha imakhala ndi chikoka chotsimikizika pamapangidwe azitsulo ndi kukula kwambewu yachitsulo chotsika, chomwe chimakhudzanso kulimba kwachitsulo chotsika. Pambuyo pozimitsa ndi kutenthetsa mankhwala, kutentha kwapansi kumawonekera bwino.
4) Malinga ndi njira zosiyanasiyana zopangira kutentha, zitsulo zotsika kutentha zimatha kugawidwa kukhala zitsulo zoponyedwa ndi zitsulo. Malinga ndi kusiyana kwa zikuchokera ndi kapangidwe metallographic, otsika kutentha zitsulo akhoza kugawidwa mu: otsika aloyi zitsulo, 6% faifi tambala zitsulo, 9% faifi tambala zitsulo, chromium-manganese kapena chromium-manganese-nickel austenitic zitsulo ndi chromium-nickel austenitic zitsulo zosapanga dzimbiri. dikirani. Chitsulo chochepa cha alloy chimagwiritsidwa ntchito kutentha pafupifupi -100 ° C popanga zipangizo za furiji, zipangizo zoyendera, zipinda zosungiramo vinyl ndi zipangizo za petrochemical. Ku United States, United Kingdom, Japan ndi mayiko ena, 9% chitsulo cha nickel chimagwiritsidwa ntchito kwambiri m'nyumba zotentha kwambiri pa 196 ° C, monga matanki osungiramo zinthu zosungiramo zinthu zosungiramo zinthu zosungiramo zinthu zakale ndi methane, zida zosungiramo mpweya wamadzimadzi. , ndi kupanga mpweya wamadzimadzi ndi nayitrogeni wamadzimadzi. Chitsulo chosapanga dzimbiri cha Austenitic ndi chinthu chabwino kwambiri chotsika kutentha. Ili ndi mphamvu yabwino yotsika kutentha, ntchito yabwino kwambiri yowotcherera, komanso kutsika kwamafuta. Amagwiritsidwa ntchito kwambiri m'minda yotentha kwambiri, monga matanki oyendera ndi matanki osungira amadzimadzi a haidrojeni ndi okosijeni wamadzimadzi. Komabe, chifukwa chokhala ndi chromium ndi faifi wochuluka, ndi okwera mtengo.
2. Mwachidule otsika kutentha zitsulo kuwotcherera kumanga
Posankha njira yopangira kuwotcherera ndi zinthu zomangira zitsulo zotsika kutentha, cholinga cha vutoli chili pazigawo ziwiri izi: kuteteza kuwonongeka kwa kulimba kwa kutentha kwapakatikati komanso kuteteza kuti pakhale ming'alu yowotcherera.
1) Bevel processing
Mawonekedwe a groove azitsulo zowotcherera zitsulo zotsika kutentha sizosiyana kwenikweni ndi zitsulo wamba za carbon, chitsulo chochepa cha alloy kapena zitsulo zosapanga dzimbiri, ndipo zimatha kuchitidwa mwachizolowezi. Koma kwa 9Ni Gang, ngodya yotsegulira poyambira ndi yabwino osati madigiri osachepera 70, ndipo m'mphepete mwake ndi yabwino osati osachepera 3mm.
Zitsulo zonse zotsika kutentha zimatha kudulidwa ndi nyali ya oxyacetylene. Kungoti liwiro kudula ndi pang'onopang'ono pamene mpweya kudula 9Ni zitsulo kuposa pamene mpweya kudula wamba mpweya structural zitsulo. Ngati makulidwe achitsulo amaposa 100mm, m'mphepete mwake mutha kutenthedwa mpaka 150-200 ° C musanayambe kudula gasi, koma osapitirira 200 ° C.
Kudula gasi kulibe zotsatira zoyipa pamadera omwe amakhudzidwa ndi kutentha kwa kuwotcherera. Komabe, chifukwa cha zitsulo zokhala ndi nickel zomwe zimakhala ndi chitsulo chodziletsa, malo odulidwawo adzaumitsa. Pofuna kuonetsetsa kuti cholumikizira chowotchereracho chimagwira ntchito bwino, ndi bwino kugwiritsa ntchito gudumu lopera pogaya pamwamba pa malo odulidwa bwino musanawotchere.
Arc gouging itha kugwiritsidwa ntchito ngati weld bead kapena chitsulo choyambira chichotsedwe pomanga kuwotcherera. Komabe, pamwamba pa mphakoyo kuyenera kukhalabe koyera musanagwiritsenso ntchito.
Oxyacetylene flame gouging sayenera kugwiritsidwa ntchito chifukwa kuopsa kutenthedwa zitsulo.
2) Kusankha njira yowotcherera
Njira zowotcherera zomwe zilipo pazitsulo zotsika kutentha zimaphatikizapo kuwotcherera kwa arc, kuwotcherera kwa arc pansi pamadzi, ndi kuwotcherera kwa electrode argon arc.
Kuwotcherera kwa Arc ndiyo njira yowotcherera yomwe imagwiritsidwa ntchito kwambiri pazitsulo zotsika kutentha, ndipo imatha kuwotcherera m'malo osiyanasiyana. The kuwotcherera kutentha athandizira ndi za 18-30KJ/cm. Ngati electrode yamtundu wa haidrojeni yotsika ikugwiritsidwa ntchito, cholumikizira chokwanira chokwanira chingapezeke. Sizinthu zamakina zokha zomwe zili zabwino, komanso kulimba kwa notch ndikwabwino. Komanso, arc kuwotcherera makina ndi yosavuta komanso yotsika mtengo, ndi ndalama zida ndi yaing'ono, ndipo si anakhudzidwa ndi udindo ndi malangizo. ubwino monga malire.
Kutentha kwachitsulo chachitsulo chotsika ndi pafupifupi 10-22KJ/cm. Chifukwa cha zida zake zosavuta, zowotcherera kwambiri komanso ntchito yabwino, imagwiritsidwa ntchito kwambiri. Komabe, chifukwa cha kutentha kwa kutentha kwa kutentha, kuzizira kumachepetsedwa, kotero pali chizoloŵezi chachikulu chopanga ming'alu yotentha. Kuonjezera apo, zonyansa ndi Si nthawi zambiri zimalowa muzitsulo zowotcherera kuchokera ku flux, zomwe zidzalimbikitsanso chizolowezi ichi. Choncho, Pamene ntchito kumizidwa arc kuwotcherera, tcherani khutu kusankha kuwotcherera waya ndi flux ndi ntchito mosamala.
Zolumikizira zowotcherera ndi CO2 zotetezedwa ndi gasi zimakhala zolimba pang'ono, kotero sizigwiritsidwa ntchito pakuwotcherera chitsulo chotsika kutentha.
Kuwotcherera kwa Tungsten argon arc (TIG kuwotcherera) nthawi zambiri kumachitika pamanja, ndipo kuwotcherera kwake kutentha kumangokhala 9-15KJ/cm. Chifukwa chake, ngakhale zolumikizira zowotcherera zili ndi zokhutiritsa kotheratu, sizikhala zosayenera pomwe makulidwe achitsulo amaposa 12mm.
Kuwotcherera kwa MIG ndi njira yowotcherera yomwe imagwiritsidwa ntchito kwambiri yodziwikiratu kapena yodziwikiratu pakuwotcherera chitsulo chotsika kutentha. Kutentha kwake kowotcherera ndi 23-40KJ/cm. Malinga ndi njira yosinthira madontho, imatha kugawidwa m'mitundu itatu: njira yosinthira kagawo kakang'ono (kulowetsa kutentha pang'ono), njira yosinthira ndege (kulowetsa kutentha kwakukulu) ndi njira yosinthira ma pulse jet (kulowetsa kutentha kwambiri). Short-circuit transition MIG kuwotcherera kuli ndi vuto la kulowa kosakwanira, ndipo chilema cha kuphatikizika koyipa chikhoza kuchitika. Mavuto omwewo amakhalapo ndi kusinthasintha kwina kwa MIG, koma pamlingo wina. Pofuna kupangitsa kuti arc ikhale yokhazikika kuti ikwaniritse bwino, maperesenti angapo mpaka makumi khumi a CO2 kapena O2 akhoza kulowetsedwa mu argon yoyera ngati mpweya wotetezera. Maperesenti oyenerera adzatsimikiziridwa poyesa chitsulo chomwe chikuwotchedwa.
3) Kusankhidwa kwa zida zowotcherera
Zida zowotcherera (kuphatikiza ndodo yowotcherera, waya wowotcherera ndi flux, ndi zina zambiri) ziyenera kutengera njira yowotcherera yomwe imagwiritsidwa ntchito. Olowa mawonekedwe ndi poyambira mawonekedwe ndi zina zofunika makhalidwe kusankha. Kwa zitsulo zotsika kutentha, chinthu chofunika kwambiri kumvetsera ndi kupanga zitsulo zowotcherera kuti zikhale ndi kutentha kwapakati kuti zifanane ndi zitsulo zoyambira, ndi kuchepetsa zomwe zili mu diffusible hydrogen mmenemo.
Xinfa kuwotcherera kuli ndi khalidwe labwino kwambiri komanso kulimba kwamphamvu, kuti mudziwe zambiri, chonde onani:https://www.xinfatools.com/welding-cutting/
(1) Aluminium deoxidized steel
Aluminium deoxidized steel ndi kalasi yachitsulo yomwe imakhudzidwa kwambiri ndi chikoka cha kuziziritsa pambuyo pakuwotcherera. Ambiri mwa maelekitirodi ntchito pamanja arc kuwotcherera a aluminiyamu deoxidized zitsulo ndi Si-Mn low-hydrogen maelekitirodi kapena 1.5% Ni ndi 2.0% Ni maelekitirodi.
Pofuna kuchepetsa kuwotcherera kutentha alowetse, zotayidwa deoxidized zitsulo zambiri utenga Mipikisano wosanjikiza kuwotcherera ndi maelekitirodi woonda wa ≤¢ 3 ~ 3.2mm, kotero kuti yachiwiri kutentha mkombero cha kumtunda wosanjikiza wa weld angagwiritsidwe ntchito kuyenga mbewu.
Kulimba kwa chitsulo chowotcherera chowotcherera ndi Si-Mn mndandanda wa elekitirodi kudzachepa kwambiri pa 50 ℃ ndikuwonjezera kwa kutentha. Mwachitsanzo, pamene kulowetsa kutentha kumawonjezeka kuchokera ku 18KJ/cm kufika ku 30KJ/cm, kulimbako kudzataya kuposa 60%. 1.5%Ni mndandanda ndi 2.5%Ni mndandanda kuwotcherera maelekitirodi si tcheru kwambiri izi, choncho ndi bwino kusankha mtundu uwu elekitirodi kwa kuwotcherera.
Kuwotcherera kwa arc pansi pamadzi ndi njira yowotcherera yodziwikiratu yopangira zitsulo za aluminiyamu deoxidized. Waya wowotcherera womwe amagwiritsidwa ntchito powotcherera pansi pamadzi ndi mtundu womwe uli ndi nickel 1.5-3.5% ndi 0.5 ~ 1.0% molybdenum.
Malinga ndi mabuku, ndi 2.5% Ni-0.8% Cr-0.5% Mo kapena 2% Ni kuwotcherera waya, chikufanana ndi flux yoyenera, pafupifupi Charpy kulimba mtengo wa weld zitsulo pa -55 ° C akhoza kufika 56-70J (5.7) ~7.1Kgf.m). Ngakhale 0.5% Mo kuwotcherera waya ndi manganese aloyi Basic flux ntchito, bola kutentha kulowetsedwa pansi pa 26KJ/cm, weld zitsulo ndi ν∑-55=55J (5.6Kgf.m) akhoza kupangidwa.
Posankha flux, chidwi chiyenera kuperekedwa pakufananitsa kwa Si ndi Mn muzitsulo zowotcherera. Umboni woyesera. Zosiyanasiyana za Si ndi Mn muzitsulo zowotcherera zidzasintha kwambiri mtengo wa Charpy. Zomwe zili mu Si ndi Mn zomwe zili ndi mtengo wolimba kwambiri ndi 0.1~0.2%Si ndi 0.7~1.1%Mn. Posankha kuwotcherera waya ndi Dziwani izi pamene soldering.
Kuwotcherera kwa Tungsten argon arc ndi kuwotcherera kwachitsulo kwa argon arc sikugwiritsidwa ntchito pang'ono muzitsulo za aluminiyamu zopanda oxidized. Mawaya akuwotcherera omwe ali pamwambawa a kuwotcherera pansi pamadzi amathanso kugwiritsidwa ntchito powotcherera argon arc.
(2) 2.5Ni chitsulo ndi 3.5Ni
Kuwotcherera arc pansi pamadzi kapena kuwotcherera kwa MIG kwa 2.5Ni chitsulo ndi chitsulo cha 3.5Ni nthawi zambiri kumatha kuwotcherera ndi waya wowotcherera womwewo monga maziko ake. Koma monga momwe fomula ya Wilkinson (5) imasonyezera, Mn ndi chinthu chotchinga chowotcha chachitsulo chotsika cha nickel low-temperature. Kusunga manganese muzitsulo zowotcherera pafupifupi 1.2% ndikopindulitsa kwambiri kupewa ming'alu yotentha monga ming'alu ya arc crater. Izi ziyenera kuganiziridwa posankha kuphatikiza waya wowotcherera ndi flux.
3.5Ni chitsulo chimakonda kukhala chokhazikika komanso chosungunula, kotero pambuyo pa kutentha kwa kutentha (mwachitsanzo, 620 ° C × 1 ola, ndiye kuzizira kwa ng'anjo) kuti athetse nkhawa yotsalira, ν∑-100 idzatsika kwambiri kuchokera ku 3.8 Kgf.m mpaka 2.1Kgf.m sangathenso kukwaniritsa zofunikira. The kuwotcherera zitsulo zopangidwa ndi kuwotcherera ndi 4.5%Ni-0.2%Mo mndandanda kuwotcherera waya ali ndi chizolowezi ang'onoang'ono kupsa mtima embrittlement. Kugwiritsa ntchito waya wowotcherera uku kungapewe zovuta zomwe zili pamwambapa.
(3) 9Ni chitsulo
9Ni zitsulo nthawi zambiri kutentha ankachitira quenching ndi tempering kapena kawiri normalizing ndi tempering kukulitsa otsika kutentha toughness. Koma chitsulo chowotcherera chachitsulo ichi sichikhoza kutenthedwa monga pamwambapa. Choncho, zimakhala zovuta kupeza chitsulo chowotcherera chokhala ndi kutentha kochepa kwambiri kofanana ndi chitsulo choyambira ngati zitsulo zopangira zitsulo zimagwiritsidwa ntchito. Pakalipano, zipangizo zowotcherera za nickel zimagwiritsidwa ntchito makamaka. Zowotcherera zomwe zimayikidwa ndi zida zowotcherera zotere zidzakhala austenitic kwathunthu. Ngakhale ili ndi kuipa kwa mphamvu yotsika kuposa 9Ni zitsulo zamtengo wapatali komanso mitengo yamtengo wapatali, fracture ya brittle siilinso vuto lalikulu kwa izo.
Kuchokera pamwambapa, zikhoza kudziwika kuti chifukwa chitsulo chowotcherera chimakhala chokhazikika, kulimba kwa kutentha kwachitsulo komwe kumagwiritsidwa ntchito powotcherera ndi maelekitirodi ndi mawaya kumafanana kwambiri ndi zitsulo zoyambira, koma mphamvu zamakokedwe ndi zokolola ndizofanana. otsika kuposa chitsulo choyambira. Chitsulo chokhala ndi nickel chimadziumitsa chokha, kotero maelekitirodi ambiri ndi mawaya amatchera khutu kuchepetsa kuchuluka kwa kaboni kuti athe kutenthetsa bwino.
Mo ndi chinthu chofunika kwambiri cholimbikitsira pazitsulo zowotcherera, pamene Nb, Ta, Ti ndi W ndizofunikira zolimbitsa thupi, zomwe zapatsidwa chidwi chonse posankha zipangizo zowotcherera.
Pamene waya wowotcherera womwewo umagwiritsidwa ntchito powotcherera, mphamvu ndi kulimba kwa chitsulo chowotcherera chazitsulo zowotcherera pansi pamadzi zimakhala zoipitsitsa kuposa za kuwotcherera kwa MIG, zomwe zingayambitsidwe ndi kuchepa kwa kuzizira kwa weld ndi kulowetsedwa kwa zonyansa kapena Si. kuchokera kutuluka kwa.
3. A333-GR6 otsika kutentha zitsulo chitoliro kuwotcherera
1) Weldability kusanthula A333-GR6 zitsulo
Chitsulo cha A333-GR6 ndi chachitsulo chotsika kutentha, kutentha kochepa kwa utumiki ndi -70 ℃, ndipo nthawi zambiri chimaperekedwa mu chikhalidwe chokhazikika kapena chokhazikika komanso chosasunthika. Chitsulo cha A333-GR6 chili ndi mpweya wochepa wa carbon, kotero chizolowezi chowumitsa ndi chizolowezi chozizira chimakhala chochepa, zinthuzo zimakhala zolimba komanso zapulasitiki, nthawi zambiri zimakhala zovuta kutulutsa zowonongeka ndi zowonongeka, ndipo zimakhala ndi weldability wabwino. ER80S-Ni1 argon arc kuwotcherera waya angagwiritsidwe ntchito Ndi W707Ni elekitirodi, ntchito argon-magetsi olowa kuwotcherera, kapena ntchito ER80S-Ni1 argon arc waya kuwotcherera, ndi ntchito zonse argon arc kuwotcherera kuonetsetsa kulimba wabwino wa mfundo zitsulo. Mtundu wa waya wowotcherera argon arc ndi ma elekitirodi amathanso kusankha zinthu zomwe zili ndi ntchito yofanana, koma zitha kugwiritsidwa ntchito ndi chilolezo cha mwiniwake.
2) kuwotcherera ndondomeko
Kuti mumve zambiri za njira zowotcherera, chonde onani buku la malangizo opangira kuwotcherera kapena WPS. Pa kuwotcherera, I-mtundu wa matako olowa ndi zonse argon arc kuwotcherera anatengera mipope ndi m'mimba mwake zosakwana 76.2 mm; kwa mapaipi okhala ndi m'mimba mwake kuposa 76.2 mm, ma grooves ooneka ngati V amapangidwa, ndipo njira yowotcherera ya argon-electric ndi argon arc priming ndi kudzaza kwamitundu yambiri imagwiritsidwa ntchito kapena Njira yowotcherera argon arc. Njira yeniyeni ndiyo kusankha njira yowotcherera yofananira malinga ndi kusiyana kwa chitoliro m'mimba mwake ndi makulidwe a khoma la chitoliro mu WPS yovomerezeka ndi mwiniwake.
3) Njira yochizira kutentha
(1) Kutenthetsa musanawotchere
Kutentha kozungulira kumakhala kotsika kuposa 5 ° C, kuwotcherera kumayenera kutenthedwa, ndipo kutentha kwa preheating ndi 100-150 ° C; mtundu wa preheating ndi 100 mm mbali zonse za weld; imatenthedwa ndi lawi la oxyacetylene (lawi losalowerera ndale), ndipo kutentha kumayezedwa Cholembera chimayesa kutentha pamtunda wa 50-100 mm kuchokera pakati pa weld, ndipo mfundo zoyezera kutentha zimagawidwa mofanana kuti ziwongolere bwino kutentha. .
(2) Chithandizo cha kutentha pambuyo pa weld
Pofuna kulimbitsa mphamvu yachitsulo chotsika kutentha, zipangizo zomwe zimagwiritsidwa ntchito nthawi zambiri zimazimitsidwa ndi kutenthedwa. Kuchiza kosayenera kwa pambuyo pa weld kutentha kumawononga ntchito yake yotsika, yomwe iyenera kulipidwa mokwanira. Choncho, kupatulapo zikhalidwe zazikulu weldment makulidwe kapena zinthu kwambiri kudziletsa, pambuyo kuwotcherera kutentha mankhwala nthawi zambiri si ikuchitika kwa otsika kutentha zitsulo. Mwachitsanzo, kuwotcherera kwa mapaipi atsopano a LPG mu CSPC sikufuna chithandizo cha kutentha pambuyo pa weld. Ngati chithandizo cha kutentha pambuyo pa weld chimafunikadi m'mapulojekiti ena, kutentha kwa kutentha, nthawi yotentha nthawi zonse ndi kuzizira kwa kutentha kwa pambuyo pa weld kuyenera kutsatiridwa motsatira malamulo awa:
Pamene kutentha kumakwera pamwamba pa 400 ℃, kutentha kwa kutentha kuyenera kusapitirira 205 × 25/δ ℃/h, ndipo sayenera kupitirira 330 ℃/h. Nthawi yotentha yokhazikika iyenera kukhala ola limodzi pa makulidwe a khoma la 25 mm, ndipo osachepera mphindi 15. Panthawi ya kutentha kosalekeza, kusiyana kwa kutentha pakati pa kutentha kwakukulu ndi kotsika kwambiri kuyenera kukhala kochepa kuposa 65 ℃.
Pambuyo pa kutentha kosalekeza, kuzizira sikuyenera kupitirira 65 × 25/δ ℃/h, ndipo sayenera kupitirira 260 ℃/h. Kuzizira kwachilengedwe kumaloledwa pansi pa 400 ℃. TS-1 mtundu zida kutentha mankhwala olamulidwa ndi kompyuta.
4) Kusamala
(1) Kutenthetsa kwambiri molingana ndi malamulo, ndikuwongolera kutentha kwa interlayer, ndipo kutentha kwapakati kumayendetsedwa pa 100-200 ℃. Msoko uliwonse wowotcherera uyenera kuwotcherera nthawi imodzi, ndipo ngati wasokonezedwa, njira zoziziritsa pang'onopang'ono ziyenera kuchitidwa.
(2) Pamwamba pa kuwotcherera ndikoletsedwa kuti zisakulidwe ndi arc. Arc crater iyenera kudzazidwa ndipo zolakwikazo ziyenera kudulidwa ndi gudumu lopera pamene arc yatsekedwa. Mgwirizano pakati pa zigawo za multilayer welding ziyenera kugwedezeka.
(3) Yang'anirani mwamphamvu mphamvu ya mzere, gwiritsani ntchito magetsi ochepa, magetsi otsika, komanso kuwotcherera mwachangu. Kuwotcherera kutalika kwa aliyense W707Ni elekitirodi ndi awiri a 3.2 mm ayenera kukhala wamkulu kuposa 8 cm.
(4) Njira yogwiritsira ntchito ya arc yayifupi ndipo palibe swing iyenera kutengedwa.
(5) Njira yonse yolowera iyenera kutengedwa, ndipo iyenera kuchitidwa motsatira zofunikira za ndondomeko yowotcherera ndondomeko ndi khadi la ndondomeko.
(6) Kulimbikitsidwa kwa weld ndi 0 ~ 2mm, ndipo m'lifupi mbali iliyonse ya weld ndi ≤ 2mm.
(7) Kuyesa kosawononga kumatha kuchitidwa osachepera maola 24 pambuyo pakuwunika kowoneka bwino kwa weld. Mawotchi a mapaipi adzakhala pansi pa JB 4730-94.
(8) "Zotengera Zopanikizika: Kuyesa Kopanda Zowonongeka kwa Zotengera Zopanikizika" muyezo, Gulu lachiwiri loyenerera.
(9) Kukonza weld kuyenera kuchitidwa musanayambe chithandizo cha kutentha kwapambuyo. Ngati kukonzanso kuli kofunika pambuyo pa chithandizo cha kutentha, weld ayenera kutenthedwanso pambuyo pokonza.
(10) Ngati mawonekedwe a geometric a weld padziko lapansi amapitilira muyezo, akupera amaloledwa, ndipo makulidwe akupera sikhala ochepa kuposa momwe amapangira.
(11) Pazovuta zonse zowotcherera, kukonzanso kuwiri kumaloledwa. Ngati kukonzanso kuwiriko sikunali koyenera, weldyo iyenera kudulidwa ndikuwotchedwanso molingana ndi ndondomeko yonse yowotcherera.
Nthawi yotumiza: Jun-21-2023
