Cikakken bincike na SMT patch da TTHT ta hanyar toshe-in PCBA uku anti fenti tsari da key fasahar!
Yayin da girman abubuwan PCBA ya zama ƙarami kuma ƙarami, yawancin ya zama mafi girma kuma mafi girma;Tsawon tsayin tallafi tsakanin na'urori da na'urori (tazara tsakanin PCB da share ƙasa) shima yana ƙara ƙarami, kuma tasirin abubuwan muhalli akan PCBA shima yana ƙaruwa.Saboda haka, mun sanya gaba mafi girma bukatun a kan amincin PCBA na lantarki kayayyakin.
1.Abubuwan muhalli da tasirin su
Abubuwan muhalli gama gari kamar zafi, ƙura, fesa gishiri, mold, da sauransu, na iya haifar da matsalolin gazawa iri-iri na PCBA
Danshi
Kusan duk kayan aikin PCB na lantarki a cikin yanayin waje suna cikin haɗarin lalata, wanda ruwa shine mafi mahimmancin matsakaici don lalata.Kwayoyin ruwa suna da ƙanƙanta don shiga ratar ƙwayar ƙwayar cuta ta wasu kayan polymer kuma su shiga ciki ko isa ga ƙarfen da ke ƙasa ta cikin ramin rufin don haifar da lalata.Lokacin da yanayi ya kai ga wani zafi, zai iya haifar da ƙaura na PCB electrochemical, yayyo halin yanzu da kuma murdiya sigina a babban mitar kewaye.
Tururi/humidity + gurɓataccen ion (gishiri, masu aiki masu aiki) = electrolytes masu aiki + ƙarfin ƙarfin damuwa = ƙaurawar lantarki
Lokacin da RH a cikin yanayi ya kai 80%, za a sami fim ɗin ruwa mai kauri na 5 ~ 20 kwayoyin halitta, kuma kowane nau'in kwayoyin halitta na iya motsawa cikin yardar kaina.Lokacin da carbon ya kasance, halayen electrochemical na iya faruwa.
Lokacin da RH ya kai 60%, saman Layer na kayan aiki zai samar da 2 ~ 4 kwayoyin ruwa mai kauri fim, lokacin da gurɓataccen abu ya narke, za a sami halayen sinadaran;
Lokacin da RH <20% a cikin yanayi, kusan dukkanin abubuwan lalata suna tsayawa.
Sabili da haka, tabbatar da danshi shine muhimmin sashi na kariyar samfur.
Don na'urorin lantarki, danshi yana zuwa nau'i uku: ruwan sama, daskarewa da tururin ruwa.Ruwa shine electrolyte wanda ke narkar da ions masu lalata da yawa masu lalata karafa.Lokacin da yawan zafin jiki na wani ɓangare na kayan aiki ya kasance ƙasa da "raɓan raɓa" (zazzabi), za a sami ƙugiya a saman: sassa na tsarin ko PCBA.
Kura
Akwai ƙura a cikin yanayi, ƙurar da ke lalata ion gurɓataccen iska ta zauna a cikin kayan aikin lantarki kuma yana haifar da gazawa.Wannan matsala ce ta gama gari tare da gazawar lantarki a fagen.
An raba kura zuwa iri biyu: m ƙura shine diamita na 2.5 ~ 15 microns na ƙwayoyin da ba su dace ba, gabaɗaya ba zai haifar da kuskure ba, arc da sauran matsalolin, amma yana shafar haɗin haɗin haɗin;Ƙaƙƙarfan ƙura shine ɓangarorin da ba daidai ba tare da diamita na ƙasa da microns 2.5.Ƙura mai kyau tana da takamaiman mannewa akan PCBA (veneer), wanda za'a iya cire shi kawai ta hanyar goga ta anti-a tsaye.
Hadarin kura: a.Saboda ƙaƙƙarfar ƙura a saman PCBA, ana haifar da lalatawar electrochemical, kuma ƙimar gazawar ta karu;b.Dust + zafi zafi + gishiri hazo ya haifar da mafi girman lalacewa ga PCBA, kuma gazawar kayan aikin lantarki shine mafi yawa a cikin masana'antar sinadarai da yankin hakar ma'adinai kusa da bakin teku, hamada (ƙasar gishiri-alkali) da kudancin kogin Huaihe a lokacin mildew kuma lokacin ruwan sama.
Saboda haka, kariyar ƙura wani muhimmin sashi ne na samfurin.
Gishiri fesa
Samuwar gishirin fesa:Ana haifar da feshin gishiri ta hanyar abubuwa na halitta kamar raƙuman ruwa, raƙuman ruwa, yanayin yanayi (damina) matsa lamba, hasken rana da sauransu.Za ta yi tafiya cikin ƙasa da iska, kuma hankalinta zai ragu tare da nisa daga bakin teku.Yawancin lokaci, yawan ƙwayar gishiri shine 1% na bakin teku lokacin da yake da nisan kilomita 1 daga bakin tekun (amma zai yi nisa a lokacin guguwa).
Illar feshin gishiri:a.lalata rufin sassan tsarin ƙarfe;b.Hanzarta saurin lalata electrochemical yana haifar da karaya na wayoyi na karfe da gazawar abubuwan da aka gyara.
Makamantan tushen lalata:a.gumi na hannu ya ƙunshi gishiri, urea, lactic acid da sauran sinadarai, waɗanda ke da tasiri iri ɗaya na lalata kayan lantarki kamar feshin gishiri.Sabili da haka, ya kamata a sa safar hannu yayin taro ko amfani da shi, kuma kada a taɓa abin rufewa da hannaye;b.Akwai halogens da acid a cikin jujjuyawar, waɗanda yakamata a tsaftace su kuma a sarrafa ragowar su.
Don haka, rigakafin feshin gishiri muhimmin bangare ne na kariyar kayayyakin.
Mold
Mildew, sunan gama gari na fungi na filamentous, yana nufin "fungi mai laushi," yakan haifar da mycelium mai ban sha'awa, amma ba sa samar da manyan jikin 'ya'yan itace kamar namomin kaza.A wurare masu dausayi da ɗumi, abubuwa da yawa suna tsirowa akan ido tsirara wasu daga cikin ƙauyuka masu kamanni, flocculent ko sifar yanar gizo, wato mold.
FIG.5: PCB al'amarin mildew
Cutarwar mold: a.mold phagocytosis da yaduwa suna sa rufin kayan aikin ya ragu, lalacewa da gazawa;b.Metabolites na mold sune kwayoyin acid, wanda ke shafar rufi da ƙarfin lantarki kuma suna samar da baka na lantarki.
Saboda haka, anti-mold wani muhimmin sashi ne na kayan kariya.
Yin la'akari da abubuwan da ke sama, dole ne a tabbatar da amincin samfurin mafi kyau, dole ne a ware shi daga yanayin waje kamar yadda zai yiwu, don haka an gabatar da tsarin suturar siffar.
Rufe PCB bayan aiwatar da shafi, a ƙarƙashin tasirin harbin fitila mai shuɗi, murfin asali na iya zama kyakkyawa sosai!
Uku anti-paint shafiyana nufin lulluɓe siriri mai kariya mai kariya a saman PCB.Ita ce hanyar shafa bayan walda da aka fi amfani da ita a halin yanzu, wani lokaci ana kiranta da rufin saman da kuma suturar daidaitawa (Sunan Ingilishi: shafi, shafi mai daidaituwa).Zai keɓe abubuwan haɗin lantarki masu mahimmanci daga yanayi mai tsauri, zai iya haɓaka aminci da amincin samfuran lantarki da tsawaita rayuwar samfuran.Uku anti-paint shafi iya kare kewaye / sassa daga muhalli dalilai kamar danshi, pollutants, lalata, danniya, girgiza, inji vibration da thermal sake zagayowar, yayin da inganta inji ƙarfi da kuma rufi halaye na samfurin.
Bayan shafi tsari na PCB, samar da wani m m fim a kan surface, iya yadda ya kamata hana ruwa da danshi kutsawa, kauce wa yayyo da kuma gajeren kewaye.
2. Main maki na shafi tsari
Dangane da buƙatun IPC-A-610E (Ma'aunin Gwajin Wutar Lantarki), galibi ana nunawa a cikin abubuwan da ke gaba:
Yanki
1. Wuraren da ba za a iya shafa su ba:
Wuraren da ke buƙatar haɗin wutar lantarki, irin su gwal na zinariya, yatsun zinariya, karfe ta ramuka, ramukan gwaji;
Batura da masu gyara baturi;
Mai haɗawa;
Fuse da casing;
Na'urar kashe zafi;
Jumper waya;
Ruwan tabarau na na'urar gani;
Potentiometer;
Sensor;
Babu maɓalli da aka rufe;
Sauran wuraren da shafa zai iya shafar aiki ko aiki.
2. Wuraren da dole ne a rufe su: duk solder gidajen abinci, fil, aka gyara da conductors.
3. Wuraren zaɓi
Kauri
Ana auna kauri akan lebur, mara tsangwama, wanda aka warke daga ɓangaren da'irar da aka buga ko akan farantin da aka makala wanda ke gudana tare da sashin.Allolin da aka makala na iya zama abu ɗaya da allunan da aka buga ko wasu kayan da ba su da ƙarfi, kamar ƙarfe ko gilashi.Hakanan za'a iya amfani da ma'aunin kaurin fim ɗin rigar azaman hanyar zaɓin zaɓi na ma'aunin kauri, muddin akwai alaƙar juzu'i tsakanin jika da busassun kauri.
Tebur 1: Matsakaicin kewayon kauri don kowane nau'in kayan shafa
Hanyar gwaji na kauri:
1. Dry film kauri kayan aiki aunawa: a micrometer (IPC-CC-830B);b Dry Fim mai kauri mai gwadawa (baƙin ƙarfe)
Hoto 9. Micrometer bushe kayan aikin fim
2. Wet film kauri ma'auni: da kauri daga rigar fim za a iya samu ta rigar fim kauri ma'auni kayan aiki, sa'an nan kuma lasafta da rabo daga manne m abun ciki.
Kauri na bushe fim
A cikin FIG.10, an sami kaurin fim ɗin rigar ta hanyar gwajin kaurin fim ɗin jika, sannan aka ƙididdige kaurin fim ɗin busasshen.
Ƙaddamarwar gefen
Ma'anarsa: A karkashin yanayi na al'ada, fesa bawul ɗin fesa daga gefen layin ba zai zama madaidaiciya ba, koyaushe za a sami wani buro.Mun ayyana nisa na burr azaman ƙudurin gefen.Kamar yadda aka nuna a ƙasa, girman d shine ƙimar ƙudurin gefen.
Lura: Ƙaddamarwar gefen tabbas ita ce mafi ƙarami, amma buƙatun abokin ciniki daban-daban ba iri ɗaya ba ne, don haka ƙayyadaddun ƙayyadaddun ƙididdiga masu rufi muddin ya dace da bukatun abokin ciniki.
Hoto 11: Kwatancen ƙudurin Edge
Daidaituwa
Manna ya kamata ya zama kamar kauri na uniform da santsi da kuma m fim da aka rufe a cikin samfurin, da girmamawa ne a kan uniformity na manne rufe a cikin samfurin sama da yankin, sa'an nan, dole ne ya zama guda kauri, babu wani tsari matsaloli: fasa, stratification, orange Lines, gurbatawa, capillary sabon abu, kumfa.
Hoto 12: Axial atomatik AC jerin atomatik shafi inji shafi sakamako, uniformity ne sosai m
3. Ganewar tsarin shafi
Tsarin sutura
1 Shirya
Shirya samfurori da manne da sauran abubuwan da ake bukata;
Ƙayyade wurin kariyar gida;
Ƙayyade cikakkun bayanan tsari na maɓalli
2: Wanke
Ya kamata a tsabtace a cikin mafi guntu lokaci bayan waldi, don hana walda datti yana da wuya a tsaftace;
Ƙayyade ko babban gurɓataccen abu ne mai iyakacin duniya, ko wanda ba na iyakacin duniya ba, don zaɓar wakili mai tsaftacewa mai dacewa;
Idan ana amfani da wakili mai tsaftace barasa, dole ne a kula da al'amuran aminci: dole ne a sami isasshen iska mai kyau da sanyaya da ka'idojin bushewa bayan wankewa, don hana ragowar sauran ƙarfi volatilization lalacewa ta hanyar fashewa a cikin tanda;
Tsabtace ruwa, tare da ruwa mai tsabta na alkaline (emulsion) don wanke ruwa, sa'an nan kuma kurkura tare da ruwa mai tsabta don tsaftace ruwa mai tsabta, don saduwa da ka'idodin tsaftacewa;
3. Kariyar abin rufe fuska (idan ba a yi amfani da kayan shafa mai zaɓi ba), wato, abin rufe fuska;
Ya kamata a zaɓi fim ɗin da ba a ɗaure ba ba zai canja wurin tef ɗin takarda ba;
Ya kamata a yi amfani da tef ɗin anti-static don kariya ta IC;
Dangane da bukatun zane-zane don wasu na'urori don kare kariya;
4. Dehumidification
Bayan tsaftacewa, PCBA mai kariya (bangaren) dole ne a riga an bushe shi kuma a cire shi kafin shafa;
Ƙayyade zafin jiki/lokacin bushewa bisa ga zafin da PCBA ya yarda (bangaren);
Ana iya ba da izinin PCBA (bangaren) don ƙayyade yawan zafin jiki/lokacin teburin bushewa
5 Tufafi
Tsarin suturar siffar ya dogara da buƙatun kariya na PCBA, kayan aikin da ake da su da kuma tanadin fasaha na yanzu, wanda galibi ana samun su ta hanyoyi masu zuwa:
a.Goga da hannu
Hoto 13: Hanyar goge hannu
Brush shafi ne mafi yadu zartar da tsari, dace da kananan tsari samar, PCBA tsarin hadaddun da m, bukatar garkuwa da kariya bukatun na m kayayyakin.Domin ana iya sarrafa murfin goga da yardar kaina, ta yadda sassan da ba a yarda su yi fenti ba za su gurɓata ba;
Rufin goge yana cinye mafi ƙarancin abu, wanda ya dace da farashin mafi girma na fenti guda biyu;
Tsarin zanen yana da manyan buƙatu akan mai aiki.Kafin ginawa, zane-zane da buƙatun sutura ya kamata a nutsar da su a hankali, a gane sunayen abubuwan PCBA, kuma sassan da ba a yarda da su ba ya kamata a yi musu alama tare da alamun kama ido;
Ba a ƙyale masu aiki su taɓa filogin da aka buga da hannayensu a kowane lokaci don guje wa gurɓatawa;
b. Tsoma da hannu
Hoto 14: Hanyar tsoma hannun hannu
Tsarin suturar tsoma yana samar da sakamako mafi kyau.Za'a iya amfani da yunifom, mai ci gaba da shafi zuwa kowane bangare na PCBA.Tsarin suturar tsoma bai dace da PCbas tare da masu iya daidaitawa ba, madaidaiciyar muryoyin maganadisu mai kyau, potentiometers, muryoyin maganadisu mai siffar kofi da wasu sassa tare da rufewa mara kyau.
Mabuɗin maɓalli na tsarin suturar tsoma:
Daidaita danko mai dacewa;
Sarrafa saurin da aka ɗaga PCBA don hana kumfa daga samuwa.Yawancin lokaci bai wuce mita 1 a sakan daya ba;
c.Fesa
Fesa ita ce mafi yawan amfani da ita, mai sauƙin yarda da hanyar aiwatarwa, zuwa kashi biyu masu zuwa:
① Yin feshi da hannu
Hoto 15: Hanyar fesa da hannu
Dace da workpiece ne mafi hadaddun, wuya a dogara da aiki da kai kayan aiki taro samar halin da ake ciki, kuma dace da samfurin line iri-iri amma kasa halin da ake ciki, za a iya fesa zuwa wani karin musamman matsayi.
Lura ga feshin hannu: hazo mai fenti zai gurɓata wasu na'urori, kamar su PCB plug-in, soket na IC, wasu lambobi masu mahimmanci da wasu sassa na ƙasa, waɗannan sassan suna buƙatar kula da amincin kariyar tsari.Wani batu kuma shi ne cewa ma'aikacin bai kamata ya taɓa filogin da aka buga da hannunsa ba a kowane lokaci don hana gurɓata fuskar filogi.
② Yin feshi ta atomatik
Yawancin lokaci yana nufin fesa atomatik tare da zaɓin kayan shafa.Dace da taro samar, mai kyau daidaito, high madaidaici, kadan gurbata muhalli.Tare da haɓaka masana'antu, haɓakar farashin aiki da ƙaƙƙarfan buƙatun kariyar muhalli, kayan aikin fesa atomatik a hankali yana maye gurbin sauran hanyoyin shafa.
Tare da karuwar buƙatun aiki da kai na masana'antu 4.0, mayar da hankali ga masana'antar ya canza daga samar da kayan aikin da suka dace don magance matsalar duk tsarin sutura.Na'ura mai zaɓaɓɓen zaɓi na atomatik - rufewa daidai kuma babu ɓata kayan abu, dace da babban adadi mai yawa, mafi dacewa da adadi mai yawa na murfin fenti guda uku.
Kwatantaatomatik shafa injikumatsarin sutura na gargajiya
PCBA na gargajiya mai huda uku-uku:
1) Rufin gogewa: akwai kumfa, raƙuman ruwa, goge gashi;
2) Rubutun: jinkirin da yawa, daidaitattun ba za a iya sarrafa su ba;
3) Jiƙa duka yanki: fenti mai ɓata sosai, jinkirin gudu;
4) Fesa gun fesa: don kare kariya, nitsewa da yawa
Rufe inji mai rufi:
1) Yawan fentin feshin, wurin fenti da wuri an saita su daidai, kuma babu buƙatar ƙara mutane don goge allo bayan fentin feshin.
2) Wasu kayan haɗin toshe tare da babban tazara daga gefen farantin za a iya fentin su kai tsaye ba tare da shigar da kayan aiki ba, adana ma'aikatan shigarwa na farantin.
3) Babu iskar gas, don tabbatar da yanayin aiki mai tsabta.
4) Duk substrate baya buƙatar yin amfani da kayan aiki don rufe fim ɗin carbon, kawar da yiwuwar haɗuwa.
5) Uku anti-paint shafi kauri uniform, ƙwarai inganta samar yadda ya dace da samfurin ingancin, amma kuma kauce wa Paint sharar gida.
PCBA atomatik uku anti Paint shafi inji, an musamman tsara don fesa uku anti Paint na fasaha fesa kayan aiki.Saboda kayan da za a fesa da ruwan feshin da ake amfani da shi ya bambanta, injin ɗin da ke cikin aikin zaɓin kayan aikin kuma ya bambanta, injin anti-paint guda uku yana ɗaukar sabon tsarin sarrafa kwamfuta, yana iya gane haɗin axis uku, a lokaci guda sanye take da tsarin saka kyamara da tsarin bin diddigi, na iya sarrafa wurin da ake fesawa daidai.
Na'ura mai hana fenti guda uku, wanda kuma aka sani da na'ura mai hana fenti guda uku, na'urar fenti mai fenti guda uku, injin fenti mai fenti guda uku, na'urar fentin fenti guda uku, na musamman don sarrafa ruwa, a saman PCB. an rufe shi da wani Layer na maganin fenti guda uku, kamar impregnation, spraying ko hanyar shafa mai a saman PCB wanda aka lulluɓe da Layer na photoresist.
Yadda za a warware sabon zamani na buƙatun maganin fenti guda uku, ya zama matsala cikin gaggawa don warwarewa a cikin masana'antar.Kayan aiki na atomatik wanda aka wakilta ta hanyar ingantacciyar na'ura mai ɗaukar hoto tana kawo sabuwar hanyar aiki,shafi daidai kuma babu ɓata kayan aiki, mafi dacewa da adadi mai yawa na murfin fenti guda uku.