20# ipayipi lensimbi elingenamthungo liyibanga lezinto ezibonakalayo elishiwo ku-GB3087-2008 “Amapayipi ensimbi angenamthungo wamabhoyela anengcindezi ephansi naphakathi”. Kuyipayipi lensimbi yensimbi engenamthungo yekhwalithi ephezulu ye-carbon structural elungele ukukhiqiza amabhayela ahlukahlukene anengcindezi ephansi kanye naphakathi. Kuyinto evamile futhi enomthamo omkhulu wepayipi lensimbi. Lapho umkhiqizi wezinto zikabhayela enza isihloko se-reheater esezingeni eliphansi, kwatholakala ukuthi kukhona amaphutha amakhulu aguquguqukayo e-crack endaweni engaphakathi yenqwaba yamajoyinti amapayipi. Impahla ehlangene yepayipi bekuyinsimbi engama-20 enencazelo engu-Φ57mm×5mm. Sahlola ipayipi lensimbi eliqhekekile futhi senza uchungechunge lokuhlola ukuze sikhiqize kabusha isici futhi sithole imbangela yokuqhekeka okuphambene.

1. Ukuhlaziywa kwesici sokuqhekeka
I-crack morphology: Kungabonakala ukuthi kunemifantu eminingi ephambanayo esabalaliswe ngobude bepayipi lensimbi. Imifantu ihlelwe ngobunono. Umfantu ngamunye unesici esimagagasi, esinokuchezuka kancane endaweni ye-longitudinal futhi akukho mihuzuko ye-longitudinal. Kukhona i-angle ethile yokuphambuka phakathi kokuqhekeka kanye nobuso bepayipi lensimbi nobubanzi obuthile. Kukhona ama-oxide kanye ne-decarburization emaphethelweni okuqhekeka. Iphansi libuthuntu futhi alukho uphawu lokunwetshwa. Isakhiwo se-matrix yi-ferrite evamile + i-pearlite, esatshalaliswa ngebhande futhi inosayizi wokusanhlamvu 8. Isizathu sokuqhekeka sihlobene nokungqubuzana phakathi kodonga lwangaphakathi lwepayipi yensimbi kanye nesikhunta sangaphakathi ngesikhathi sokukhiqizwa ipayipi lensimbi.

Ngokwezici ze-macroscopic kanye ne-microscopic morphological of the crack, kungase kuthiwe ukuqhekeka kwakhiqizwa ngaphambi kokwelashwa kokushisa kokugcina kwepayipi lensimbi. Ipayipi lensimbi lisebenzisa ishubhu eliyindilinga elingu-Φ90mm billet. Izinqubo zokwakheka eziyinhloko ebhekana nazo ukubhoboza okushisayo, ukugoqa okushisayo nokunciphisa ububanzi, kanye nemidwebo emibili ebandayo. Inqubo ethize iwukuthi i-Φ90mm round tube billet igoqelwa ku-Φ93mm×5.8mm ishubhu elimahhadla, bese ishisa igoqwe futhi yehliselwe ku-Φ72mm×6.2mm. Ngemuva kokukhetha nokugcoba, umdwebo wokuqala obandayo wenziwa. Ukucaciswa ngemuva komdwebo obandayo ngu-Φ65mm×5.5mm. Ngemuva kokukhishwa kwe-annealing okuphakathi, ukukhethwa, nokugcotshwa, umdwebo wesibili obandayo uyenziwa. Ukucaciswa ngemuva komdwebo obandayo ngu-Φ57mm×5mm.

Ngokusho kokuhlaziywa kwenqubo yokukhiqiza, izici ezithinta ukungqubuzana phakathi kodonga lwangaphakathi lwepayipi lensimbi kanye nokufa kwangaphakathi ngokuyinhloko kuyikhwalithi yokugcoba futhi zihlobene nepulasitiki yepayipi yensimbi. Uma i-plasticity yepayipi yensimbi impofu, kungenzeka ukuthi ukudweba imifantu kuzokwanda kakhulu, futhi i-plasticity empofu ihlobene nokwelashwa kokucindezeleka okuphakathi kwe-annealing heat. Ngokusekelwe kulokhu, kucatshangwa ukuthi imifantu ingase ikhiqizwe kunqubo yokudweba ebandayo. Ngaphezu kwalokho, ngenxa yokuthi imifantu ayivulwanga ngezinga elikhulu futhi akukho sibonakaliso esicacile sokwandisa, kusho ukuthi imifantu ayizange ithole ithonya le-deformation yesibili yokudweba ngemva kokwakhiwa, ngakho-ke kuphinde kuqondiswe ukuthi kungenzeka kakhulu. isikhathi sokuthi imifantu yenziwe kufanele kube inqubo yesibili yokudweba ebandayo. Izici ezingaba nomthelela kakhulu ukungagcobi kahle kanye/noma ukuncishiswa okuncane kokukhululeka kwengcindezi.

Ukuze kutholakale imbangela yokuqhekeka, ukuhlolwa kokukhiqizwa kabusha kwe-crack kwenziwa ngokubambisana nabakhiqizi bepayipi lensimbi. Ngokusekelwe ekuhlaziyweni okungenhla, kwenziwa lezi zivivinyo ezilandelayo: Ngaphansi kwesimo sokuthi izinqubo zokunciphisa ukubhobozwa kanye nokuginqika okushisayo zihlala zingashintshile, ukugcotshwa kanye/noma izimo zokwelapha ukushisa okudambisa ingcindezi kuyashintshwa, futhi amapayipi ensimbi adonswe ahlolwe ukuze zama ukukhiqiza kabusha amaphutha afanayo.

2. Uhlelo lokuhlola
Izinhlelo zokuhlola eziyisishiyagalolunye zihlongozwa ngokushintsha inqubo yokugcoba kanye nemingcele yenqubo yokudonsa. Phakathi kwazo, imfuneko evamile ye-phosphating kanye nesikhathi sokugcotshwa yi-40min, imfuneko evamile yokunciphisa ingcindezi emaphakathi yi-830 ℃, kanti imfuneko yesikhathi sokufaka esijwayelekile yi-20min. Inqubo yokuhlola isebenzisa iyunithi yokudweba ebandayo engu-30t kanye nesithando somlilo sokushisa esingaphansi.

3. Imiphumela yokuhlolwa
Ngokuhlola amapayipi ensimbi akhiqizwa amapulani angu-9 angenhla, kwatholakala ukuthi ngaphandle kwezinhlelo 3, 4, 5, no-6, ezinye izinhlelo zinemifantu enyakazayo noma ephambanayo ngamazinga ahlukahlukene. Phakathi kwabo, uhlelo 1 lwalunesinyathelo sonyaka; izikimu 2 no-8 zazinemifantu ephambanayo, futhi i-crack morphology yayifana kakhulu naleyo etholakala ekukhiqizeni; amasu 7 no-9 ayezamazama, kodwa akuzange kutholakale imifantu enqamulayo.

4. Ukuhlaziya kanye nengxoxo
Ngochungechunge lokuhlola, kwaqinisekiswa ngokugcwele ukuthi ukugcotshwa kanye nokunciphisa ingcindezi kwamaphakathi phakathi nenqubo yokudweba okubandayo kwamapayipi ensimbi kunomthelela obalulekile kwikhwalithi yamapayipi ensimbi aqediwe. Ikakhulukazi, ama-scheme 2 no-8 akhiqize kabusha amaphutha afanayo odongeni lwangaphakathi lwepayipi yensimbi etholakala ekukhiqizeni okungenhla.

I-Scheme 1 iwukwenza umdwebo wokuqala obandayo eshubhuni likamama eligoqiwe elincishisiwe ngaphandle kokwenza inqubo ye-phosphating neyokugcoba. Ngenxa yokuntuleka kokugcoba, umthwalo odingekayo ngesikhathi senqubo yokudweba okubandayo usufinyelele umthwalo omkhulu womshini wokudweba obandayo. Inqubo yokudweba ebandayo inzima kakhulu. Ukunyakaziswa kwepayipi lensimbi kanye nokungqubuzana nesikhunta kubangela izinyathelo ezicacile odongeni lwangaphakathi lwethubhu, okubonisa ukuthi lapho i-plasticity ye-tube yomama ihle, nakuba umdwebo ongasetshenzisiwe unomphumela omubi, akulula ukubangela. imifantu ephambene. Kuhlelo lwesi-2, ipayipi lensimbi elinephosphating eliphansi kanye nokugcobisa lidonswa ngokuqhubekayo ngaphandle kokuncishiswa kwengcindezi okumaphakathi, okuholela ekuqhekekeni okufanayo okuphambene. Kodwa-ke, kuSikimu sesi-3, azikho iziphambeko ezitholakele emdwebeni obandayo oqhubekayo wepayipi lensimbi elinephosphating enhle kanye nokugcoba ngaphandle kokunciphisa ukucindezeleka okumaphakathi, okubonisa ngaphambilini ukuthi ukugcotshwa okungalungile kuyimbangela eyinhloko yokuqhekeka okuphambene. Amasu 4 kuya ku-6 awokushintsha inqubo yokwelapha ukushisa kuyilapho eqinisekisa ukugcotshwa kahle, futhi akukho kulimala kokudweba okwenzeke ngenxa yalokho, okubonisa ukuthi ukunqanyulwa kwengcindezi okumaphakathi akuyona into ehamba phambili eholela ekuveleni kwemifantu ephambanayo. Amasu 7 kuya ku-9 ashintsha inqubo yokwelapha ukushisa ngenkathi efinyeza isikhathi se-phosphating nesokugcoba ngesigamu. Ngenxa yalokho, amapayipi ensimbi eSikimu 7 no-9 anemigqa enyakazayo, futhi iSikimu 8 sikhiqiza imifantu efanayo ephambanayo.

Ukuhlaziywa okuqhathanisayo okungenhla kukhombisa ukuthi imifantu evundlile izokwenzeka kuzo zombili izimo zokugcotshwa okubi + akukho ukuncibilika okuphakathi nendawo kanye nokugcotshwa okungekuhle + izinga lokushisa eliphansi le-anneal elimaphakathi. Ezimeni zokuthambisa okungekuhle + ukuthungatha okuhle okuphakathi, ukugcotshwa okuhle + akukho ukuthungathwa okuphakathi nendawo, kanye nokugcotshwa okuhle + izinga lokushisa eliphansi le-annealing eliphakathi nendawo, nakuba ukukhubazeka komugqa wokuzamazama kuzokwenzeka, imifantu ephambanayo ngeke yenzeke odongeni lwangaphakathi lwepayipi lensimbi. Ukugcotshwa okungalungile kuyimbangela eyinhloko yokuqhekeka okuguquguqukayo, kanye nokungafinyeleli kahle kokukhululeka kwengcindezi okumaphakathi kuyimbangela eyisizayo.

Njengoba ukucindezeleka komdwebo wepayipi yensimbi ilingana namandla okungqubuzana, ukugcoba okungahambi kahle kuzoholela ekwandeni kwamandla okudweba nokunciphisa izinga lokudweba. Ijubane liphansi uma ipayipi lensimbi lidonswa okokuqala. Uma ijubane liphansi kunenani elithile, okungukuthi, lifinyelela iphuzu le-bifurcation, i-mandrel izokhiqiza ukudlidliza okuzithokozisayo, okuholela ekunyakazeni imigqa. Endabeni yokugcoba okwanele, ukungqubuzana kwe-axial phakathi kwendawo (ikakhulukazi indawo yangaphakathi) yensimbi kanye nokufa ngesikhathi sokudweba kwanda kakhulu, okuholela ekusebenzeni kanzima. Uma izinga lokushisa elilandelanayo lokukhulula ingcindezi ekufakweni kokushisa kwepayipi lensimbi linganele (njengokuthi cishe 630 ℃ okusethwe ekuhlolweni) noma lingekho i-anneal, kulula ukubangela ukuqhekeka kwendawo.

Ngokwezibalo zethiyori (izinga lokushisa eliphansi kakhulu le-recrystallization ≈ 0.4×1350℃), izinga lokushisa lokuphinda libe yi-20# yensimbi licishe libe ngu-610℃. Uma izinga lokushisa le-annealing liseduze nezinga lokushisa le-recrystallization, ipayipi lensimbi lihluleka ukuvuselela ngokugcwele, futhi ukuqina komsebenzi akuqediwe, okuholela epulasitikini yezinto ezibonakalayo, ukugeleza kwensimbi kuvinjiwe ngesikhathi sokungqubuzana, futhi izingqimba zensimbi zangaphakathi nangaphandle zinzima kakhulu. ikhubazekile ngokungalingani, ngaleyo ndlela idale ingcindezi enkulu ye-axial eyengeziwe. Ngenxa yalokho, ukucindezeleka kwe-axial yensimbi yangaphakathi yensimbi yepayipi yensimbi idlula umkhawulo wayo, ngaleyo ndlela ikhiqize imifantu.

5. Isiphetho
Ukukhiqizwa kwemifantu evundlile odongeni lwangaphakathi lwepayipi lensimbi engenamthungo elingu-20# kubangelwe umphumela ohlangene wokugcotshwa okungekuhle ngesikhathi sokudweba kanye nokuntuleka okwanele kokuqeda ingcindezi okumaphakathi kokwelashwa kokushisa (noma ukungaxhumi). Phakathi kwazo, ukugcotshwa okungalungile kuyimbangela eyinhloko, futhi ukuncipha kokucindezelwa okumaphakathi okungekuhle (noma ukunganciphisi) kuyimbangela eyisizayo. Ukuze ugweme amaphutha afanayo, abakhiqizi kufanele bafune ukuthi opharetha bamaworkshop balandele ngokuqinile imithethonqubo yezobuchwepheshe efanele yenqubo yokugcoba nokushisa ekukhiqizeni. Ngaphezu kwalokho, njengoba isithando somlilo esiqhubekayo se-roller-bottom siyisithando somlilo esiqhubekayo, nakuba kulula futhi kuyashesha ukulayisha nokulayisha, kunzima ukulawula izinga lokushisa kanye nesivinini sezinto ezicacisiwe kanye nobukhulu obuhlukahlukene esithandweni somlilo. Uma kungenziwanga ngokuqinile ngokuvumelana nemithethonqubo, kulula ukubangela izinga lokushisa le-anneal elingalingani noma isikhathi esifushane kakhulu, okuholela ekungeneni kabusha kwekristalu okwanele, okuholela ekulimaleni ekukhiqizeni okulandelayo. Ngakho-ke, abakhiqizi abasebenzisa izithando zokushisa eziqhubekayo ze-roller-bottom zokwelashwa kokushisa kufanele balawule izidingo ezihlukahlukene kanye nokusebenza kwangempela kokwelashwa kokushisa.