埋弧焊不銹鋼管焊接參數比焊條電弧焊多一些,包括焊接電流、電弧電壓、焊接速度、焊接材料、焊絲直徑、焊絲偏移量、焊絲干伸長度、焊絲輸送速度等。


①. 焊接電流


   焊(han)接電(dian)流(liu)的(de)(de)大(da)小直接影響焊(han)接熔(rong)池(chi)(chi)的(de)(de)深淺(qian),焊(han)接電(dian)流(liu)大(da),熱輸(shu)入(ru)大(da)、電(dian)弧挺度大(da),焊(han)接熔(rong)池(chi)(chi)深;反之(zhi)則淺(qian)。當焊(han)接電(dian)流(liu)較大(da)時(shi),由于熔(rong)深較深,而(er)焊(han)縫(feng)(feng)寬(kuan)度變化不(bu)大(da),所得到的(de)(de)焊(han)縫(feng)(feng)成形(xing)系(xi)數(焊(han)縫(feng)(feng)的(de)(de)寬(kuan)度與(yu)焊(han)縫(feng)(feng)有(you)效厚度的(de)(de)比值稱為焊(han)縫(feng)(feng)成形(xing)系(xi)數)較小。這樣(yang)的(de)(de)焊(han)縫(feng)(feng),對熔(rong)池(chi)(chi)中(zhong)氣體和夾渣物(wu)的(de)(de)上浮(fu)和溢出(chu)十分不(bu)利(li),易產生氣孔(kong)、夾渣和熱裂(lie)紋。所以(yi)一般(ban)增加(jia)電(dian)流(liu)時(shi),必(bi)須(xu)相應的(de)(de)提高電(dian)弧電(dian)壓,以(yi)保(bao)證得到合理的(de)(de)焊(han)縫(feng)(feng)形(xing)狀,一般(ban)焊(han)縫(feng)(feng)成形(xing)系(xi)數控制在(zai)1.3~2.0之(zhi)間,這樣(yang)對熔(rong)池(chi)(chi)中(zhong)的(de)(de)氣體溢出(chu)以(yi)及防止產生夾渣或熱裂(lie)紋等缺陷有(you)利(li)。


②. 電弧電壓


   電(dian)弧(hu)電(dian)壓(ya)隨著電(dian)弧(hu)長度(du)的(de)變化而變化,電(dian)弧(hu)拉長了,電(dian)弧(hu)電(dian)壓(ya)則升高,電(dian)弧(hu)挺度(du)下(xia)降,母材受熱面增加,所(suo)以焊(han)(han)接熔池的(de)深(shen)度(du)減小(xiao),焊(han)(han)縫(feng)寬度(du)明顯增寬。適(shi)當的(de)增加電(dian)弧(hu)電(dian)壓(ya),會(hui)提高焊(han)(han)縫(feng)質量(liang),但(dan)應與增加焊(han)(han)接電(dian)流相配(pei)合(he)。單(dan)純地(di)增加電(dian)弧(hu)電(dian)壓(ya),會(hui)使熔深(shen)減小(xiao),造(zao)成(cheng)焊(han)(han)件未焊(han)(han)透。而且(qie)焊(han)(han)劑的(de)熔化量(liang)大(da),增加焊(han)(han)劑的(de)消(xiao)耗量(liang)。焊(han)(han)縫(feng)表面粗糙,脫渣困難,嚴重時,會(hui)造(zao)成(cheng)焊(han)(han)縫(feng)邊(bian)緣咬邊(bian)。


③. 焊接速度


   當(dang)焊(han)(han)(han)(han)接電(dian)流和電(dian)弧電(dian)壓不變時,焊(han)(han)(han)(han)接速度(du)提高(gao),電(dian)弧給予焊(han)(han)(han)(han)接熔(rong)(rong)池中(zhong)單位(wei)長度(du)的(de)熱量勢必(bi)減(jian)少(shao),導致焊(han)(han)(han)(han)縫(feng)熔(rong)(rong)深(shen)和焊(han)(han)(han)(han)縫(feng)寬度(du)減(jian)小。過分的(de)增(zeng)加(jia)焊(han)(han)(han)(han)接速度(du),會導致焊(han)(han)(han)(han)接電(dian)弧對(dui)工件的(de)加(jia)熱不足(zu),造(zao)成焊(han)(han)(han)(han)件未焊(han)(han)(han)(han)透和邊(bian)緣(yuan)未熔(rong)(rong)合等缺陷(xian)。


④. 焊接材料(liao)


   a. 壓力容(rong)器常(chang)用(yong)(yong)不銹(xiu)(xiu)鋼埋弧焊(han)(han)(han)(han)焊(han)(han)(han)(han)絲(si)、焊(han)(han)(han)(han)劑(ji)(ji)見表(biao)4-14,常(chang)用(yong)(yong)奧氏體(ti)(ti)型(xing)耐熱鋼埋弧焊(han)(han)(han)(han)焊(han)(han)(han)(han)劑(ji)(ji)與焊(han)(han)(han)(han)絲(si)見表(biao)4-15,結構件常(chang)用(yong)(yong)奧氏體(ti)(ti)不銹(xiu)(xiu)鋼埋弧焊(han)(han)(han)(han)焊(han)(han)(han)(han)劑(ji)(ji)與焊(han)(han)(han)(han)絲(si)見表(biao)4-16。


    b.  常(chang)用不銹鋼埋(mai)弧焊用焊劑烘焙要(yao)求見表(biao) 4-17 。


   c. 焊劑(ji)顆粒度。熔煉焊劑(ji)顆粒度為2.5~0.45mm(4~40目),燒結焊劑(ji)顆粒度為2~0.28mm(10~60目),焊劑(ji)允許重復(fu)(fu)使(shi)用(yong),但重復(fu)(fu)使(shi)用(yong)前須(xu)篩出細粉和渣殼(ke),并(bing)與新焊劑(ji)混(hun)勻后使(shi)用(yong)。





 ⑤. 焊絲直(zhi)徑


   焊絲直徑加(jia)粗,電(dian)弧范(fan)圍擴大(da),使熔寬增加(jia);如果焊接(jie)電(dian)流(liu)保持(chi)不變,電(dian)流(liu)密度減小,電(dian)弧挺度下降(jiang),則熔深將相應地減小。


 ⑥. 焊絲偏移量a


    焊(han)(han)(han)接(jie)環焊(han)(han)(han)縫(feng)時(shi)(shi),焊(han)(han)(han)絲(si)不(bu)應在最高點或(huo)最低點,而(er)應在下(xia)坡焊(han)(han)(han)的位置(zhi)上,如圖(tu)4-19所(suo)(suo)示。焊(han)(han)(han)絲(si)偏(pian)移(yi)量(liang)(liang)直(zhi)(zhi)接(jie)影響焊(han)(han)(han)縫(feng)成(cheng)形,見(jian)(jian)圖(tu)4-18。焊(han)(han)(han)絲(si)偏(pian)移(yi)量(liang)(liang)與焊(han)(han)(han)件外(wai)徑和(he)焊(han)(han)(han)接(jie)線(xian)能量(liang)(liang)有(you)關。當(dang)焊(han)(han)(han)接(jie)線(xian)能量(liang)(liang)大(da)時(shi)(shi),熔(rong)池停留時(shi)(shi)間較(jiao)長,所(suo)(suo)以焊(han)(han)(han)絲(si)偏(pian)移(yi)量(liang)(liang)可選較(jiao)大(da)值。當(dang)焊(han)(han)(han)接(jie)線(xian)能量(liang)(liang)小(xiao)時(shi)(shi),熔(rong)池停留時(shi)(shi)間較(jiao)短,所(suo)(suo)以焊(han)(han)(han)絲(si)偏(pian)移(yi)量(liang)(liang)選取較(jiao)小(xiao)值。當(dang)焊(han)(han)(han)件外(wai)徑較(jiao)大(da)時(shi)(shi),熔(rong)池中(zhong)的液態金屬(shu)外(wai)溢的傾(qing)向較(jiao)小(xiao),此時(shi)(shi),焊(han)(han)(han)絲(si)偏(pian)移(yi)量(liang)(liang)可取較(jiao)大(da)值。焊(han)(han)(han)絲(si)直(zhi)(zhi)徑小(xiao)于3mm時(shi)(shi),焊(han)(han)(han)絲(si)偏(pian)移(yi)量(liang)(liang)一般不(bu)超(chao)過(guo)5~10mm,焊(han)(han)(han)絲(si)直(zhi)(zhi)徑大(da)于3mm時(shi)(shi),焊(han)(han)(han)絲(si)偏(pian)移(yi)量(liang)(liang)見(jian)(jian)表(biao)4-18。


18.jpg


 ⑦. 焊絲(si)干伸長度(du)L


    焊絲(si)前端到導電(dian)嘴前端的(de)距(ju)離稱為焊絲(si)干(gan)伸(shen)長(chang)度(du)(du),見(jian)圖4-20。焊絲(si)干(gan)伸(shen)長(chang)度(du)(du)L增加,焊絲(si)的(de)預熱溫度(du)(du)增加,焊絲(si)熔化(hua)速(su)度(du)(du)增加,增加焊絲(si)干(gan)伸(shen)長(chang)度(du)(du)可提(ti)高生產效率,但焊絲(si)干(gan)伸(shen)長(chang)度(du)(du)超過(guo)50mm后(hou)會(hui)出現成段爆(bao)裂現象。所以(yi)焊絲(si)干(gan)伸(shen)長(chang)度(du)(du)一般控制(zhi)在17~20mm范圍內。


 ⑧. 電流種類和電極極性


    在一般(ban)情況下,電(dian)(dian)(dian)(dian)(dian)弧(hu)陽極(ji)(ji)(ji)區(qu)(qu)的(de)溫(wen)(wen)度(du)(du)較陰(yin)極(ji)(ji)(ji)區(qu)(qu)的(de)溫(wen)(wen)度(du)(du)高,但在使(shi)用高錳高硅含(han)氟的(de)焊(han)(han)劑(ji)進行(xing)埋弧(hu)焊(han)(han)時,電(dian)(dian)(dian)(dian)(dian)弧(hu)空(kong)間氣體的(de)電(dian)(dian)(dian)(dian)(dian)離(li)勢增加(jia),這樣,氣體電(dian)(dian)(dian)(dian)(dian)離(li)后(hou)正離(li)子釋放至陰(yin)極(ji)(ji)(ji)的(de)能量(liang)也增加(jia),使(shi)陰(yin)極(ji)(ji)(ji)的(de)溫(wen)(wen)度(du)(du)提(ti)高,并大(da)(da)于陽極(ji)(ji)(ji)的(de)溫(wen)(wen)度(du)(du)。因而在用含(han)有高電(dian)(dian)(dian)(dian)(dian)離(li)電(dian)(dian)(dian)(dian)(dian)位的(de)埋弧(hu)焊(han)(han)劑(ji)時,若焊(han)(han)接電(dian)(dian)(dian)(dian)(dian)源(yuan)(yuan)為(wei)直(zhi)流(liu)(liu)正接,則焊(han)(han)絲(si)的(de)熔(rong)(rong)(rong)化速(su)度(du)(du)大(da)(da)于焊(han)(han)件(jian)的(de)熔(rong)(rong)(rong)化速(su)度(du)(du),使(shi)接頭熔(rong)(rong)(rong)深減小,焊(han)(han)縫(feng)余高增加(jia)。反之用直(zhi)流(liu)(liu)反接便可增加(jia)熔(rong)(rong)(rong)深。使(shi)用交流(liu)(liu)焊(han)(han)接電(dian)(dian)(dian)(dian)(dian)源(yuan)(yuan)時,對形狀的(de)影響介于直(zhi)流(liu)(liu)正接、反接之間。


  上述各(ge)項(xiang)焊(han)(han)接(jie)(jie)參(can)數(shu)的(de)選擇,不能(neng)(neng)(neng)單項(xiang)考慮,要(yao)有機地匹配,進行(xing)綜合平衡分(fen)析,找出(chu)(chu)一個主(zhu)要(yao)焊(han)(han)接(jie)(jie)參(can)數(shu),在(zai)充分(fen)試驗后,才能(neng)(neng)(neng)制訂出(chu)(chu)最(zui)佳(jia)參(can)數(shu)。最(zui)終要(yao)經過焊(han)(han)接(jie)(jie)接(jie)(jie)頭(tou)的(de)力學性(xing)能(neng)(neng)(neng)考核和耐(nai)腐蝕性(xing)能(neng)(neng)(neng)試驗(即(ji)焊(han)(han)接(jie)(jie)工藝評定合格(ge)),滿足產品設計圖樣要(yao)求后,方能(neng)(neng)(neng)在(zai)產品上正式施焊(han)(han)。表(biao)4-19、表(biao)4-20所列出(chu)(chu)的(de)18-8型奧氏體不銹鋼焊(han)(han)接(jie)(jie)參(can)數(shu)可供參(can)考。







聯系方式.jpg