Thereflow tandaAna amfani da shi don siyar da abubuwan haɗin guntu na SMT zuwa allon kewayawa a cikin tsarin sarrafa kayan aikin SMT.Tanderun da aka sake fitarwa ya dogara ne da kwararar iska mai zafi a cikin tanderun don goge man da aka yi a kan mahaɗin solder ɗin da ke da alaƙa da keɓaɓɓiyar allo, ta yadda za a sake narkar da solder ɗin a cikin kwano mai ruwa ta yadda sassan guntu na SMT da allon kewayawa. ana welded da welded, sa'an nan kuma reflow soldering Ana sanyaya tanderun don samar da solder gidajen abinci, da kuma colloidal solder manna sha wani jiki dauki karkashin wani high zafin jiki iska kwarara don cimma nasarar soldering na tsarin SMT.
The soldering a reflow tanda ne zuwa kashi hudu matakai.Ana jigilar allunan da'ira tare da abubuwan smt ta hanyar raƙuman jagorar tanda ta hanyar yankin preheating, yankin adana zafi, yankin mai sanyaya, da yankin sanyaya na tanda mai jujjuya bi da bi, sannan bayan reflow soldering.Yankunan zafin jiki guda huɗu na tanderun sun samar da cikakkiyar ma'anar walda.Bayan haka, sayar da reflow na Guangshengde zai bayyana ka'idodin yankunan zafin jiki guda huɗu na tanda mai sake juyewa bi da bi.
Preheating shine don kunna man na'urar solder, da kuma guje wa saurin zafi mai zafi yayin nutsar da tin, wanda shine aikin dumama wanda aka yi don haifar da lahani.Manufar wannan yanki shine a ɗora PCB a zafin jiki da wuri-wuri, amma yakamata a sarrafa ƙimar dumama a cikin kewayon da ya dace.Idan ya yi sauri sosai, girgizar zafin jiki zai faru, kuma allon kewayawa da abubuwan da aka gyara na iya lalacewa.Idan yayi jinkiri sosai, sauran ƙarfi ba zai ƙafe sosai ba.Ingancin walda.Saboda saurin dumama da sauri, bambance-bambancen zafin jiki a cikin tanderun da aka sake fitarwa ya fi girma a ƙarshen yankin zafin jiki.Domin hana thermal girgiza daga žata da aka gyara, matsakaicin dumama kudi ne kullum kayyade a matsayin 4 ℃ / S, da kuma tashin kudi yawanci saita a 1 ~ 3 ℃ / S.
Babban maƙasudin mataki na adana zafi shine daidaita yanayin zafin kowane sashi a cikin tanderun da aka sake fitarwa da kuma rage bambancin zafin jiki.Ba da isasshen lokaci a cikin wannan yanki don sanya yanayin zafi na babban bangaren ya kama da ƙarami, kuma don tabbatar da cewa jujjuyawar da ke cikin manna mai siyar ya kasance cikakke.A ƙarshen sashin kula da zafi, ana cire oxides akan pads, ƙwallan solder da fitilun kayan aiki a ƙarƙashin aikin jujjuyawar, kuma yanayin zafin jiki duka yana daidaitawa.Ya kamata a lura cewa duk abubuwan da aka gyara akan SMA yakamata su sami zafin jiki iri ɗaya a ƙarshen wannan sashe, in ba haka ba, shigar da sashin reflow zai haifar da mugayen abubuwan siyarwa daban-daban saboda rashin daidaituwar zafin jiki na kowane sashi.
Lokacin da PCB ya shiga yankin reflow, zafin jiki yana tashi da sauri ta yadda manna mai siyar ya kai matsayin narkakkar.Wurin narkewar manna gubar 63sn37pb shine 183°C, kuma wurin narkewar manna gubar 96.5Sn3Ag0.5Cu shine 217°C.A cikin wannan yanki, ana saita yawan zafin jiki mai zafi, don haka zafin jiki ya tashi da sauri zuwa ƙimar darajar.Yawan zafin jiki na madaidaicin magudanar ruwa ana ƙididdige shi ta wurin zafin narkewar mai siyar da zafin juriya na ma'auni da aka haɗa.A cikin reflow sashe, da soldering zafin jiki dabam dangane da solder manna amfani.Gabaɗaya, babban zafin jiki na gubar shine 230-250 ℃, kuma zazzabin gubar shine 210-230 ℃.Idan zafin jiki ya yi ƙasa sosai, yana da sauƙi don samar da haɗin gwiwar sanyi da rashin isasshen wetting;idan yawan zafin jiki ya yi yawa, coking da delamination na epoxy guduro substrate da filastik sassa suna iya faruwa, da kuma wuce kima eutectic karfe mahadi za su samar, wanda zai kai ga gaggautsa solder gidajen abinci, wanda zai shafi waldi ƙarfi .A cikin reflow soldering yankin, ba da kulawa ta musamman ga lokacin sake dawowa don kada ya yi tsayi da yawa, don hana lalacewar wutar lantarki, yana iya haifar da mummunan ayyuka na kayan lantarki ko kuma ya sa allon kewayawa ya ƙone.
A wannan mataki, ana sanyaya zafin jiki zuwa ƙasa da ƙaƙƙarfan zafin lokaci don ƙarfafa haɗin gwiwar solder.Adadin sanyaya zai shafi ƙarfin haɗin haɗin siyar.Idan yanayin sanyaya ya yi jinkiri sosai, zai haifar da samar da mahadi masu yawa na eutectic, kuma manyan sifofi na hatsi suna da saurin faruwa a gidajen haɗin gwanon, wanda zai rage ƙarfin haɗin gwiwar solder.A sanyaya kudi a cikin sanyaya yankin ne kullum game da 4 ℃ / S, da kuma sanyaya kudi ne 75 ℃.iya.
Bayan brushing da solder manna da hawa smt guntu aka gyara, da kewaye jirgin ana hawa ta hanyar dogo na jagora na reflow soldering makera, da kuma bayan da mataki na hudu zafin jiki zones sama da reflow soldering tanderu, an kafa cikakken soldered hukumar kewaye.Wannan shi ne duk ka'idar aiki na sake kwarara tanda.
Lokacin aikawa: Yuli-29-2020