家用電器不銹鋼化的首要問題就是可能會增加成本。即便如此,全自動不銹鋼桶洗衣機、滾筒式洗滌干燥機由于其清潔性,耐用性銷售量爆發式大增,繼而家用電器全部不銹鋼化,就連衣類干燥機也由表面處理鋼板改為不銹鋼。


1. 洗衣機(ji)


  無論何種洗衣機都是要和水接觸,因此大多數洗衣機都是先用不銹鋼的代表鋼種06Cr19Ni10(304)。也可以選用0022Cr18Ti(439)、019Cr17MoNb(436L)等可進行深度拉深的鋼種,可作為洗衣機的首選鋼種。它在制造洗衣機洗滌桶時,無論是采用焊接結構或是鉚接結構,均可以確保有足夠的耐腐蝕性能。


  洗衣(yi)機加工(gong)(gong)(gong)時(shi)使(shi)(shi)用(yong)厚度0.5mm或(huo)0.6mm的(de)(de)(de)(de)不(bu)銹(xiu)鋼薄板,采(cai)(cai)(cai)(cai)用(yong)焊接(jie)(jie)(jie)方(fang)(fang)法(fa)或(huo)是(shi)鉚(liu)接(jie)(jie)(jie)方(fang)(fang)法(fa)制(zhi)造。洗滌(di)桶(tong)的(de)(de)(de)(de)中間桶(tong)體可(ke)以采(cai)(cai)(cai)(cai)用(yong)不(bu)銹(xiu)鋼卷材或(huo)板材采(cai)(cai)(cai)(cai)用(yong)壓沖(chong)工(gong)(gong)(gong)藝(yi)進行(xing)(xing)連(lian)續(xu)加工(gong)(gong)(gong)業(ye)。為脫水而設置許多小孔,使(shi)(shi)用(yong)沖(chong)床的(de)(de)(de)(de)沖(chong)頭(凸模(mo))進行(xing)(xing)沖(chong)孔,為了使(shi)(shi)洗滌(di)物不(bu)被(bei)劃傷,要施行(xing)(xing)去毛刺(ci)(ci)工(gong)(gong)(gong)序,將所(suo)有沖(chong)孔的(de)(de)(de)(de)毛刺(ci)(ci)、銳(rui)(rui)邊(bian)(bian)、尖角去除(chu),然(ran)后壓制(zhi)出像洗衣(yi)板樣的(de)(de)(de)(de)凸點,接(jie)(jie)(jie)著進行(xing)(xing)桶(tong)體卷圓成形(xing)(xing)(xing)。對(dui)接(jie)(jie)(jie)部(bu)分采(cai)(cai)(cai)(cai)用(yong)TIG焊接(jie)(jie)(jie)方(fang)(fang)式(shi)和鉚(liu)接(jie)(jie)(jie)方(fang)(fang)式(shi)進行(xing)(xing)連(lian)接(jie)(jie)(jie)。然(ran)后,桶(tong)腹部(bu)的(de)(de)(de)(de)上沿其邊(bian)(bian)緣要進行(xing)(xing)卷邊(bian)(bian),使(shi)(shi)其形(xing)(xing)(xing)成圓形(xing)(xing)(xing)邊(bian)(bian)緣。下部(bu)分則要和不(bu)銹(xiu)鋼桶(tong)底相(xiang)接(jie)(jie)(jie)合。不(bu)銹(xiu)鋼桶(tong)底,采(cai)(cai)(cai)(cai)用(yong)鉚(liu)接(jie)(jie)(jie)方(fang)(fang)式(shi)較多。鉚(liu)接(jie)(jie)(jie)方(fang)(fang)式(shi)有如(ru)上所(suo)述幾種加工(gong)(gong)(gong)工(gong)(gong)(gong)序,為了防止產(chan)生毛刺(ci)(ci)、銳(rui)(rui)角或(huo)尖邊(bian)(bian),加工(gong)(gong)(gong)時(shi)需要潤滑,大多數是(shi)采(cai)(cai)(cai)(cai)用(yong)在(zai)不(bu)銹(xiu)鋼薄板上貼附表面保護薄膜的(de)(de)(de)(de)狀態下,進行(xing)(xing)加工(gong)(gong)(gong)。但(dan)是(shi),如(ru)采(cai)(cai)(cai)(cai)用(yong)TIG焊接(jie)(jie)(jie)方(fang)(fang)式(shi),因(yin)表面保護薄膜而不(bu)利(li)于焊接(jie)(jie)(jie),可(ke)改用(yong)在(zai)焊接(jie)(jie)(jie)過程中自行(xing)(xing)揮(hui)(hui)發(fa)狀態的(de)(de)(de)(de)揮(hui)(hui)發(fa)性加工(gong)(gong)(gong)油,以實現(xian)連(lian)續(xu)性批量(liang)生產(chan)。采(cai)(cai)(cai)(cai)用(yong)TIG焊接(jie)(jie)(jie)方(fang)(fang)式(shi)的(de)(de)(de)(de)焊接(jie)(jie)(jie)速度是(shi)產(chan)量(liang)和生產(chan)成本的(de)(de)(de)(de)關鍵工(gong)(gong)(gong)序。


  滾筒式(shi)洗滌干燥(zao)機,由于具有干燥(zao)功能(neng),要進行(xing)加熱(re)干燥(zao),所以(yi)必須使用(yong)不(bu)銹(xiu)鋼桶(tong)。因(yin)不(bu)銹(xiu)鋼桶(tong)是(shi)雙(shuang)層結構,所以(yi)一臺不(bu)銹(xiu)鋼用(yong)量相當于原來的2臺以(yi)上。在選(xuan)定材料和(he)加工方法方面,基(ji)本上和(he)上述(shu)全自動洗滌機類(lei)似。


2. 電熱水器(qi)


  制作(zuo)不(bu)銹鋼(gang)熱水罐曾(ceng)沿用06Cr19Ni10(304),但(dan)多(duo)次發生(sheng)應(ying)力腐(fu)蝕開裂(lie)(lie)問(wen)題。鐵素(su)體系(xi)列不(bu)銹鋼(gang)019Cr19Mo2NbTi(444),對防止應(ying)力腐(fu)蝕開裂(lie)(lie)是一種(zhong)完美對策(ce)。雖(sui)然使用鐵素(su)體系(xi)列不(bu)銹鋼(gang),但(dan)熱水罐上下(xia)封頭與筒體接(jie)合(he)處仍有零(ling)星間隙(xi)腐(fu)蝕發生(sheng),加強焊接(jie)質量及接(jie)合(he)部間隙(xi)的管理問(wen)題即可解決。


  裝配(pei)間隙(xi)過于(yu)狹窄(zhai)是造成間隙(xi)腐蝕(shi)的(de)原因。所以有必要適(shi)當(dang)加大裝配(pei)間隙(xi)。對回收的(de)舊電熱水(shui)器熱水(shui)罐內部進行調查,由于(yu)使(shi)(shi)用(yong)了019Cr19Mo2NbTi(444)而(er)使(shi)(shi)熱水(shui)罐內部幾乎沒(mei)有腐蝕(shi),質量(liang)事故多(duo)使(shi)(shi)其他(ta)零(ling)部件損(sun)壞而(er)不能(neng)使(shi)(shi)用(yong)。可以說,電熱水(shui)器筒體的(de)不銹鋼化(hua),是“機能(neng)材料選定”最(zui)適(shi)合的(de)產品。


  加工方面:上(shang)、下封頭使(shi)(shi)用厚度為(wei)1.0~1.2mm的(de)(de)不銹(xiu)鋼薄板,沖壓而(er)成(cheng)。筒體選用0.6~0.8mm的(de)(de)不銹(xiu)鋼薄板,采(cai)用TIG焊接。考慮到熱水器上(shang)部(bu)因水位高低的(de)(de)變(bian)(bian)化(hua),使(shi)(shi)得(de)氣相(xiang)和液(ye)相(xiang)在上(shang)部(bu)反復交替(ti)變(bian)(bian)化(hua),進而(er)氯離子濃(nong)(nong)度在逐漸變(bian)(bian)濃(nong)(nong),易產生(sheng)腐(fu)蝕,所以上(shang)部(bu)的(de)(de)焊縫應(ying)從內部(bu)焊接。


  圖(tu)(tu)6-5是熱水器內結構膽示意圖(tu)(tu)及可(ke)能出(chu)現腐(fu)蝕。


圖 5.jpg


  熱水(shui)器內膽(dan)加工工藝流程(cheng):下(xia)料→沖(chong)壓封頭→加工出入水(shui)孔(kong)→卷筒→焊接筒體→焊接上下(xia)封頭→耐壓檢驗。