A cikin aikin samar da injunan takarda, nadi iri-iri suna taka rawar da ba za a iya ba, tun daga ɓarkewar jikayar yanar gizo zuwa saitin busassun yanar gizo. A matsayin daya daga cikin mahimman fasahohin da ke cikin ƙirar na'urar takarda, "kambi" - duk da alamar bambance-bambancen geometric da ya ƙunshi - kai tsaye yana ƙayyade daidaituwa da kwanciyar hankali na ingancin takarda. Wannan labarin zai yi cikakken nazarin fasahar kambi na injin takarda daga bangarorin ma'anar, ƙa'idar aiki, rarrabuwa, mahimman abubuwan da ke tasiri a cikin ƙira, da kiyayewa, yana bayyana mahimmancin ƙimarsa a cikin samar da takarda.

1. Ma'anar Crown: Muhimmin Aiki a Ƙananan Bambance-bambance

“Crown” (wanda aka bayyana a Turanci a matsayin “Crown”) musamman yana nufin wani tsari na geometric na musamman na injin takarda yana birgima tare da axial direction (tsawon tsayi). Diamita na tsakiyar yanki na jikin nadi yana da ɗan girma fiye da na ƙarshen yankunan, yana samar da kwane-kwane mai kama da "digon kugu". Wannan bambance-bambancen diamita yawanci ana auna shi ne a cikin micrometers (μm), kuma ƙimar kambi na wasu manyan naɗaɗɗen latsa na iya kaiwa 0.1-0.5 mm.

Mahimmin ma'auni don auna ƙirar kambi shine "ƙimar kambi", wanda aka ƙididdige shi a matsayin bambanci tsakanin matsakaicin diamita na jikin mirgina (yawanci a tsakiyar tsakiya na axial direction) da diamita na mirgina ya ƙare. A zahiri, ƙirar rawanin ya ƙunshi saita wannan ɗan ƙaramin bambance-bambancen diamita don daidaita nakasar "tsakiyar sag" na nakasar da abubuwan da ke haifar da su kamar ƙarfi da canjin yanayi yayin aiki na ainihi. Daga ƙarshe, yana cimma daidaitattun rarraba matsi na lamba a cikin faɗin faɗin saman nadi da gidan yanar gizo na takarda (ko wasu abubuwan haɗin gwiwa), yana shimfiɗa tushe mai ƙarfi don ingancin takarda.

2. Muhimman Ayyuka na Crown: Rage lalacewa da Kula da Matsi na Uniform

A lokacin aikin na'ura na takarda, nakasawa ba makawa ne saboda nauyin injina, canjin yanayin zafi, da sauran dalilai. Ba tare da zane na kambi ba, wannan nakasar zai haifar da matsa lamba mara daidaituwa tsakanin saman mirgine da gidan yanar gizon takarda - "mafi girma matsa lamba a duka iyakar da ƙananan matsa lamba a tsakiya" - kai tsaye yana haifar da manyan batutuwa masu inganci irin su rashin daidaito nauyi da rashin daidaituwa na dewatering na takarda. Babban darajar kambi ya ta'allaka ne a cikin rayayye ramawa ga waɗannan nakasar, wanda ke bayyana musamman a cikin abubuwan da ke biyowa:

2.1 Ramuwa don Nakasar Lankwasawa

Lokacin da ainihin na'urorin na'urorin takarda, kamar latsawa rolls da calender rolls, ke aiki, suna buƙatar yin matsa lamba mai mahimmanci ga gidan yanar gizon takarda. Misali, matsa lamba na layi na latsawa na iya kaiwa 100-500 kN/m. Don rolls tare da babban girman tsayi-zuwa diamita (misali, tsayin latsawa a cikin injunan takarda mai faɗi na iya zama mita 8-12), nakasar lankwasa ta ƙasa a tsakiya tana faruwa a ƙarƙashin matsin lamba, kama da “ƙarancin sandar kafada ƙarƙashin kaya”. Wannan nakasawa yana haifar da matsananciyar lamba mai yawa tsakanin iyakar juyi da gidan yanar gizon takarda, yayin da matsa lamba a tsakiya bai isa ba. Sakamakon haka, gidan yanar gizon takarda ya zama ruwan sama a duka iyakar (sakamakon babban bushewa da ƙananan nauyin nauyi) da kuma rashin ruwa a tsakiya (sakamakon rashin bushewa da nauyin nauyi).

Duk da haka, tsarin "dimbin ganga" na zane na rawanin yana tabbatar da cewa bayan an lanƙwasa nadi, gabaɗayan saman nadi ya kasance a layi daya tare da gidan yanar gizon takarda, yana samun rarraba matsa lamba iri ɗaya. Wannan yana magance ingantattun haɗarin da ke haifarwa ta hanyar lanƙwasawa.

2.2 Ramuwa don Nakasar Rubutun Thermal

Wasu nadi, kamar nadi na jagora da jujjuyawar kalanda a cikin sashin bushewa, suna fuskantar faɗaɗa yanayin zafi yayin aiki saboda tuntuɓar yanar gizo na takarda mai zafi da dumama tururi. Tun da tsakiyar ɓangaren juzu'i ya fi zafi sosai (ƙarshen suna da alaƙa da bearings kuma suna watsar da zafi da sauri), haɓakar zafinta ya fi na ƙarshen, yana haifar da "kumburi na tsakiya" na jikin nadi. A wannan yanayin, yin amfani da ƙirar kambi na al'ada zai kara tsananta matsa lamba mara daidaituwa. Sabili da haka, "kambi mara kyau" (inda diamita na tsakiya ya ɗan ƙarami fiye da na ƙarshen, wanda kuma aka sani da "kambin baya") yana buƙatar tsarawa don daidaita ƙarin haɓakar haɓakar haɓakar thermal, yana tabbatar da matsa lamba iri ɗaya akan saman nadi.

2.3 Matsakaicin Rarraba Rarraba Sayen Sama

A lokacin aiki na dogon lokaci, wasu naɗaɗɗen naɗaɗɗen (kamar latsa na roba) suna fuskantar rikice-rikice akai-akai a gefuna na gidan yanar gizon takarda (kamar yadda gefuna na gidan yanar gizo ke ɗaukar ƙazanta), yana haifar da saurin lalacewa a ƙarshen fiye da tsakiyar. Ba tare da zane-zane na kambi ba, saman mirgina zai nuna "bugewa a tsakiya da sag a ƙarshen" bayan lalacewa, wanda hakan yana rinjayar rarraba matsa lamba. Ta hanyar saita kambi, ana iya kiyaye daidaiton kwandon saman nadi a farkon matakin lalacewa, tsawaita rayuwar sabis ɗin nadi da rage haɓakar samarwa da lalacewa ta haifar.

3. Rarraba Sarauta: Zaɓuɓɓukan Fasaha waɗanda Aka Daidaita zuwa Yanayin Aiki daban-daban

Dangane da nau'in na'ura na takarda (ƙananan sauri / babban sauri, kunkuntar nisa / nisa), aikin mirgine (latsawa / calending / jagora), da buƙatun tsari, za a iya raba kambi zuwa nau'ikan daban-daban. Daban-daban nau'ikan kambi sun bambanta cikin halayen ƙira, hanyoyin daidaitawa, da yanayin aikace-aikacen, kamar yadda cikakken bayani a cikin tebur mai zuwa:

4. Mabuɗin Mahimman Abubuwan Tasiri a Tsarin Crown: Madaidaicin ƙididdigewa don daidaitawa da buƙatun samarwa

Ba a saita ƙimar kambi ba bisa ka'ida ba; yana buƙatar ƙididdige ƙididdigewa bisa ga sigogin nadi da yanayin tsari don tabbatar da ingantaccen aikinsa. Mahimman abubuwan da ke tasiri ƙirar kambi sun haɗa da abubuwa masu zuwa:

4.1 Mirgine Girma da Material

1. Mirgine Tsawon Jikin (L): Mafi tsayin jikin nadi, mafi girma nakasar lankwasawa a ƙarƙashin matsi guda ɗaya, don haka ya fi girma darajar kambin da ake bukata. Misali, dogayen nadi a cikin injunan takarda mai faɗin suna buƙatar ƙimar kambi mai girma fiye da gajeriyar juzu'i a cikin injunan takarda mai faɗi don rama nakasar.
2. Nadin Jikin Diamita (D): Karami na diamita na jikin nadi, ƙananan tsattsauran ra'ayi, kuma mafi sauƙin jujjuya shi ne nakasawa a ƙarƙashin matsin lamba. Saboda haka, ana buƙatar ƙimar kambi mai girma. Sabanin haka, rolls tare da diamita mafi girma suna da tsayin daka mafi girma, kuma za a iya rage darajar kambi daidai.
3. Material Rigidity: Abubuwan daban-daban na jikin mirgine suna da rigidity daban-daban; misali, Rolls na karfe suna da tsayin daka fiye da simintin ƙarfe. Kayayyakin da ke da ƙananan ƙarfi suna nuna nakasar da ta fi girma a ƙarƙashin matsin lamba, suna buƙatar ƙimar kambi mai girma.

4.2 Matsin Aiki (Matsi na Layi)

Matsin aiki (matsi na layi) na rolls kamar latsawa rolls da calender rolls wani muhimmin al'amari ne da ke tasiri ƙirar kambi. Mafi girman matsi na linzamin kwamfuta, mafi mahimmancin nakasar lankwasawa na jikin bidi'a, kuma darajar rawanin yana buƙatar ƙarawa daidai da haka don daidaita nakasar. Ana iya bayyana dangantakar su da ƙayyadaddun tsari: Ƙimar darajar Crown H ≈ (P × L³)/(48×E×I), inda P shine matsi na linzamin kwamfuta, L shine tsayin yi, E shine ma'auni na kayan aiki, kuma ni shine lokacin rashin aiki na ɓangaren giciye. Misali, matsi na linzamin kwamfuta na latsa don takarda marufi yawanci ya fi 300 kN/m, don haka ƙimar kambi mai dacewa yana buƙatar ya fi girma fiye da na latsawa don takarda al'adu tare da matsananciyar madaidaiciya.

4.3 Gudun Inji da Nau'in Takarda

1. Gudun inji: Lokacin da injunan takarda mai sauri (gudun> 1200 m / min) ke aiki, gidan yanar gizo na takarda ya fi damuwa da daidaituwar matsa lamba fiye da na injunan takarda mai sauri. Ko da ƙananan matsi na iya haifar da lahani ingancin takarda. Saboda haka, injunan takarda masu sauri yawanci suna ɗaukar "kambi mai sarrafawa" don gane ainihin lokacin ramuwa don nakasa mai ƙarfi da tabbatar da matsa lamba.
2. Nau'in Takarda: Nau'in takarda daban-daban suna da buƙatu daban-daban don daidaituwar matsa lamba. Takardar nama (misali, takarda bayan gida mai nauyin tushe na 10-20 g/m²) tana da ƙananan nauyi kuma tana da matuƙar kula da jujjuyawar matsin lamba, tana buƙatar ƙirar kambi mai tsayi. Sabanin haka, takarda mai kauri (misali, kwali mai nauyin tushe na 150-400 g/m²) yana da ƙarfin jure jure jure juyi, don haka ana iya saukar da buƙatun madaidaicin rawanin yadda ya kamata.

5. Batutuwa gama gari da Kulawa: Binciken Kan lokaci don Tabbatar da Ƙarfafa Ƙarfafawa

Ƙirar kambi mara ma'ana ko kulawa mara kyau zai shafi ingancin takarda kai tsaye kuma ya haifar da jerin matsalolin samarwa. Matsalolin rawanin gama gari da matakan da suka dace sune kamar haka:

5.1 Girman Girman Girman Girman Girma

Ƙimar kambi mai girma da yawa yana haifar da matsananciyar matsa lamba a tsakiyar filin nadi, yana haifar da ƙananan nauyin nauyi da babban bushewar takarda a tsakiya. A lokuta masu tsanani, yana iya haifar da "murkushewa" (karyewar fiber), yana shafar ƙarfi da bayyanar takarda.

Hanyoyin magancewa: Don ƙayyadaddun kambi na kambi da aka yi amfani da su a cikin injunan takarda mai ƙananan sauri, ya zama dole don maye gurbin rolls tare da darajar kambi mai dacewa. Don jujjuyawar kambi mai sarrafawa a cikin injunan takarda mai sauri, za a iya rage matsa lamba na hydraulic ko pneumatic ta hanyar tsarin kambi mai sarrafawa don rage darajar kambi har sai an rarraba matsa lamba.

5.2 Ƙimar Ƙarfin Kambi Mai Girma

Ƙimar ƙanƙara mai ƙanƙara da ta wuce kima yana haifar da rashin isasshen matsi a tsakiyar filin nadi, yana haifar da rashin isasshen ruwa na takarda a tsakiya, ƙananan bushewa, babban nauyin nauyi, da lahani mai kyau kamar "rigakafi". A lokaci guda kuma, yana iya shafar ingancin tsarin bushewa na gaba.

Hanyoyin magancewa: Don ƙayyadaddun mirgina kambi, jikin nadi yana buƙatar sake sarrafa shi don ƙara ƙimar kambi. Don jujjuyawar kambi mai sarrafawa, ana iya ƙara matsa lamba na hydraulic ko pneumatic don haɓaka darajar kambi, tabbatar da cewa matsa lamba a tsakiyar ya cika ka'idodin tsari.

5.3 Rashin daidaituwa na Kwakwalwa na Crown

Bayan aiki na dogon lokaci, saman nadi zai fuskanci lalacewa. Idan suturar ba ta dace ba, kwandon rawanin zai zama nakasu, kuma "rauni mara kyau" zai bayyana a saman nadi. Wannan yana ƙara haifar da lahani irin su "raguwa" da "ƙasa" a kan takarda, yana da matukar tasiri ga ingancin bayyanar takarda.

Hanyoyin magancewa: A kai a kai duba saman nadi. Lokacin da lalacewa ya kai wani matakin, lokaci mai niƙa da gyara saman yi (misali, regrind da kambi kwane-kwane na latsa roba Rolls) don mayar da al'ada siffar da girman da kambi da kuma hana wuce kima lalacewa daga shafi samarwa.

6. Kammalawa

A matsayin da alama da dabara amma fasaha mai mahimmanci, kambi na injin takarda shine ainihin don tabbatar da ingancin takarda iri ɗaya. Daga kafaffen kambi a cikin injunan takarda mai ƙarancin sauri zuwa kambi mai sarrafawa a cikin injunan takarda mai sauri, mai faɗi mai faɗi, ci gaba da haɓaka fasahar kambi koyaushe ya dogara ne akan ainihin manufar "ramawa nakasawa da cimma matsa lamba", daidaitawa da bukatun daban-daban na yin aiki na takarda takarda. Ƙirar kambi mai ma'ana ba kawai yana warware matsalolin inganci kamar nauyin takarda maras kyau ba da rashin ruwa mara kyau amma kuma yana inganta ingantaccen aiki na inji na takarda (rage yawan karya takarda) kuma yana rage yawan makamashi (gujewa kan bushewa). Yana da mahimmancin tallafin fasaha mai mahimmanci a cikin ci gaban masana'antar takarda zuwa "high quality, high quality, and low energy energy". A cikin samar da takarda na gaba, tare da ci gaba da inganta kayan aiki na kayan aiki da ci gaba da ingantawa na matakai, fasahar kambi za ta zama mai ladabi da hankali, yana ba da gudummawa ga ingantaccen ci gaban masana'antar takarda.