Mu PCBA processing, kuwotcherera khalidwe la bolodi dera zimakhudza kwambiri ntchito ndi maonekedwe a bolodi dera. Choncho, n'kofunika kwambiri kulamulira kuwotcherera khalidwe la bolodi PCB dera.Pulogalamu ya PCBkuwotcherera khalidwe n'zogwirizana kwambiri ndi kapangidwe bolodi dera, zipangizo ndondomeko, luso kuwotcherera ndi zinthu zina.
一、Kupanga kwa board board ya PCB
1. Padi kapangidwe
(1) Popanga mapadi a zigawo za pulagi, kukula kwa pad kuyenera kupangidwa moyenera. Ngati pediyo ndi yaikulu kwambiri, malo ofalitsa solder ndi aakulu, ndipo zogwirizanitsa zomwe zimapangidwira sizimadzaza. Kumbali inayi, kugwedezeka kwapamwamba kwa zojambulazo zamkuwa za pad yaying'ono ndizochepa kwambiri, ndipo ma solder opangidwa ndi osakanikirana osanyowa. Kusiyana kofananira pakati pa kabowo ndi kabowo ndi kokulirapo ndipo ndikosavuta kuyambitsa kusokeretsa kwabodza. Pamene pobowo ndi 0.05 - 0.2mm m'lifupi kuposa kutsogolera ndi pedi awiri ndi 2 - 2.5 nthawi pobowo, ndi yabwino kuwotcherera.
(2) Popanga mapepala a zigawo za chip, mfundo zotsatirazi ziyenera kuganiziridwa: Kuti athetse "mthunzi wa mthunzi" momwe zingathere, malo otsekemera kapena zikhomo za SMD ziyenera kuyang'anizana ndi kayendetsedwe ka tini kuti tiyendetse. kukhudzana ndi kutuluka kwa tini. Chepetsani kugulitsa zabodza komanso kuperewera kwa soldering. Zigawo zing'onozing'ono siziyenera kuikidwa pambuyo pa zigawo zazikulu kuti ziteteze zigawo zazikuluzikulu kuti zisasokoneze kayendedwe ka solder ndi kukhudzana ndi mapepala a zigawo zing'onozing'ono, zomwe zimapangitsa kuti pakhale kutuluka kwa soldering.
2, PCB dera gulu flatness kulamulira
Wave soldering ali ndi zofunika kwambiri pa flatness ya matabwa osindikizidwa. Nthawi zambiri, tsamba lankhondo liyenera kukhala lochepera 0.5mm. Ngati ndi wamkulu kuposa 0.5mm, iyenera kuphwanyidwa. Makamaka, makulidwe a matabwa ena osindikizidwa ndi pafupifupi 1.5mm, ndipo zofunikira zawo zamasamba ndizokwera kwambiri. Apo ayi, khalidwe la kuwotcherera silingatsimikizidwe. Zinthu zotsatirazi ziyenera kutsatiridwa:
(1) Sungani bwino matabwa osindikizidwa ndi zigawo zake ndikufupikitsa nthawi yosungiramo momwe mungathere. Pa kuwotcherera, zojambula zamkuwa ndi chigawo chotsogolera chopanda fumbi, mafuta, ndi ma oxides zimathandizira kupanga zida zogulitsira zoyenerera. Choncho, matabwa osindikizidwa ndi zigawo zikuluzikulu ziyenera kusungidwa pamalo ouma. , m’malo oyera, ndi kufupikitsa nthawi yosungiramo momwe mungathere.
(2) Kwa matabwa osindikizidwa omwe aikidwa kwa nthawi yaitali, pamwamba pake amafunika kutsukidwa. Izi zitha kupititsa patsogolo kugulitsa ndikuchepetsa kugulitsa zabodza ndi kutsekereza. Pazikhomo zamagulu okhala ndi mlingo winawake wa okosijeni pamwamba, pamwamba ayenera kuchotsedwa poyamba. oxide wosanjikiza.
二. Kuwongolera kwapamwamba kwazinthu zopangira
Mu wave soldering, zida zazikulu zomwe zimagwiritsidwa ntchito ndi: flux ndi solder.
1. Kugwiritsa ntchito flux kumatha kuchotsa oxides pamtunda wowotcherera, kuteteza kukonzanso makutidwe ndi okosijeni wa solder ndi kuwotcherera pamwamba pa kuwotcherera, kuchepetsa kugwedezeka kwa pamwamba pa solder, ndikuthandizira kusamutsa kutentha kumalo otsekemera. Flux imakhala ndi gawo lofunikira pakuwongolera khalidwe la kuwotcherera.
2. Kuwongolera khalidwe la solder
Tin-lead solder ikupitiriza kukhala oxidize pa kutentha kwakukulu (250 ° C), kuchititsa kuti malata omwe ali mu solder ya malata mumphika achepetse mosalekeza ndikuchoka ku eutectic point, zomwe zimachititsa kuti madzi aziyenda bwino komanso mavuto amtundu uliwonse monga mosalekeza. soldering, soldering yopanda kanthu, ndi kusakwanira kwa mgwirizano wa solder mphamvu. .
三、Kuwotcherera ndondomeko parameter ulamuliro
Chikoka cha kuwotcherera ndondomeko magawo pa kuwotcherera pamwamba khalidwe ndi zovuta.
Pali mfundo zingapo zazikulu: 1. Kuwongolera kutentha kwa preheating. 2. Kuwotcherera njanji kupendekera ngodya. 3. Wave crest kutalika. 4. Kutentha kwa kutentha.
Kuwotcherera ndi njira yofunika kwambiri pakupanga ma board a PCB. Pofuna kuonetsetsa kuti zitsulo zowotcherera za bolodi la dera, munthu ayenera kukhala wodziwa bwino njira zoyendetsera khalidwe ndi luso la kuwotcherera.
