摘要:塔式熔鹽吸(xi)熱器是光熱發電(dian)系統中最重(zhong)要(yao)的設(she)備(bei)之一,其制造(zao)方式與常規鍋爐產品存在很大差別。本文主(zhu)要(yao)闡(chan)述了塔式光熱發電(dian)吸(xi)熱器的結構特點、制造(zao)難(nan)點及解決(jue)方案。
引言
隨著(zhu)環境問題的(de)(de)加劇(ju),可(ke)再生能(neng)源(yuan)已成為(wei)(wei)各國(guo)能(neng)源(yuan)戰略的(de)(de)重(zhong)中(zhong)之(zhi)重(zhong)。為(wei)(wei)避免不(bu)穩定能(neng)源(yuan)對(dui)電(dian)(dian)網造(zao)成沖擊(ji),各地(di)方(fang)電(dian)(dian)網針對(dui)新上風電(dian)(dian)、光伏出臺了配(pei)備(bei)(bei)儲能(neng)的(de)(de)要求(qiu)。在當前技(ji)術條(tiao)件下(xia),以光伏作為(wei)(wei)可(ke)再生能(neng)源(yuan)發(fa)電(dian)(dian)項目儲能(neng)方(fang)式(shi)綜合成本較低(di),市場前景(jing)廣(guang)闊(kuo)。塔(ta)式(shi)熔(rong)鹽吸熱(re)器是光熱(re)發(fa)電(dian)(dian)系統中(zhong)最重(zhong)要的(de)(de)設(she)備(bei)(bei)之(zhi)一,我公(gong)司與某業主共同研發(fa)設(she)計吸熱(re)器設(she)備(bei)(bei),該(gai)設(she)備(bei)(bei)采用薄(bo)壁鎳(nie)基管排連接不(bu)銹鋼集箱的(de)(de)結(jie)構(gou),受光部分進行(xing)吸熱(re)涂料噴(pen)涂,內部介質為(wei)(wei)熔(rong)鹽,運行(xing)工況惡劣,需進行(xing)每(mei)日啟停,其(qi)制造(zao)方(fang)式(shi)與常規鍋爐(lu)產品(pin)存在很大差別,有必(bi)要對(dui)其(qi)制造(zao)工藝技(ji)術進行(xing)專門的(de)(de)研究。
1工作原理與結構特點
1.1工作原理
在塔(ta)式熔鹽太(tai)(tai)陽能發電系統中(zhong),熔鹽吸(xi)熱(re)(re)(re)器(qi)是實(shi)現(xian)太(tai)(tai)陽能發電最(zui)為關鍵(jian)的(de)設備之一(yi),來自電站(zhan)冷(leng)(leng)罐的(de)冷(leng)(leng)熔鹽通過入口緩沖(chong)罐進入多塊(kuai)吸(xi)熱(re)(re)(re)器(qi)吸(xi)熱(re)(re)(re)板,吸(xi)收來自鏡場的(de)熱(re)(re)(re)量,熔鹽在最(zui)后一(yi)塊(kuai)吸(xi)熱(re)(re)(re)板的(de)末端達到(dao)其額(e)定出口溫度,加熱(re)(re)(re)后的(de)熔鹽流過出口緩沖(chong)罐到(dao)達電站(zhan)的(de)熱(re)(re)(re)罐,并(bing)從熱(re)(re)(re)罐通過泵(beng)輸送到(dao)蒸(zheng)汽發生系統,實(shi)現(xian)太(tai)(tai)陽能從光能到(dao)熱(re)(re)(re)能的(de)轉化(hua)。
1.2結構特點
吸熱(re)器(qi)主要由(you)吸熱(re)管、上(shang)下(xia)部(bu)(bu)集箱、支撐桁架(jia)等(deng)幾部(bu)(bu)分組成(cheng),并且需(xu)要在廠內安裝保溫(wen)、電伴熱(re)后方可出廠,吸熱(re)器(qi)結構見圖1。吸熱(re)管采用鎳基薄壁(bi)管,由(you)中間直管加兩(liang)端(duan)彎(wan)管組成(cheng),管子壁(bi)厚薄且長,中間直管需(xu)焊接鎳基附件,兩(liang)端(duan)彎(wan)管與不(bu)銹鋼(gang)集箱連(lian)接;吸熱(re)管受光部(bu)(bu)分需(xu)噴涂太陽能高溫(wen)吸熱(re)涂料(liao),涂料(liao)噴涂前需(xu)對待涂表面進行(xing)預處(chu)理(li)以保證涂層性(xing)能滿足設(she)計(ji)要求。
圖1吸熱器結構
2制造工藝流程
1)吸熱管(guan)兩端(duan)彎管(guan):下料(管(guan)接(jie)(jie)頭(tou)和彎頭(tou))→管(guan)接(jie)(jie)頭(tou)機加→接(jie)(jie)長(chang)→彎管(guan)→通球(qiu)→與中(zhong)間直管(guan)接(jie)(jie)長(chang)。
2)吸熱管(guan)中(zhong)間直管(guan):定尺來料→去余(yu)量(liang)→加(jia)工坡口→裝焊附(fu)件→清理油污→噴(pen)砂→與兩端彎管(guan)接長→通球→總裝。
3)總裝(zhuang):放樣→裝(zhuang)焊管(guan)束→裝(zhuang)焊集箱端蓋→水壓→油漆→漆膜固化(hua)→裝(zhuang)焊桁架→裝(zhuang)保(bao)溫、電伴(ban)熱→油漆包(bao)裝(zhuang)。
3難點分析與解決辦法
3.1薄壁鎳基管彎管
吸熱管(guan)采用薄壁(bi)(bi)鎳基管(guan),由于材質(zhi)為新材質(zhi)且管(guan)壁(bi)(bi)較薄,彎(wan)(wan)管(guan)時易出現變形(xing)及凹坑,且彎(wan)(wan)管(guan)存在空間彎(wan)(wan)結構(gou),空間角(jiao)度不易控制。彎(wan)(wan)管(guan)變形(xing)情況見圖2。
圖2薄壁(bi)鎳基管(guan)彎管(guan)變形(xing)
解決辦法:針對(dui)(dui)彎(wan)(wan)(wan)管(guan)(guan)(guan)變形問(wen)題,對(dui)(dui)彎(wan)(wan)(wan)管(guan)(guan)(guan)工裝進行優化,改進彎(wan)(wan)(wan)管(guan)(guan)(guan)模型腔尺寸,使其更(geng)適用于(yu)薄壁管(guan)(guan)(guan)彎(wan)(wan)(wan)制,反復調試彎(wan)(wan)(wan)管(guan)(guan)(guan)參數,同時(shi)對(dui)(dui)模具不夠圓滑的(de)表面進行修(xiu)磨(mo),避免造成(cheng)彎(wan)(wan)(wan)管(guan)(guan)(guan)表面凹坑,最終使吸熱(re)管(guan)(guan)(guan)彎(wan)(wan)(wan)管(guan)(guan)(guan)質量滿足標準要求。
3.2薄壁鎳基管焊接
鎳基(ji)(ji)材料(liao)極易氧化,同(tong)時(shi)薄(bo)壁(bi)管(guan)散熱慢容(rong)易超溫(wen),所以(yi)鎳基(ji)(ji)薄(bo)壁(bi)管(guan)焊接(jie)易發生氧化變色,見圖3,焊接(jie)附件時(shi),由于管(guan)子(zi)壁(bi)厚太薄(bo),極易焊漏(lou)在管(guan)子(zi)內壁(bi)形成鼓包,見圖4;薄(bo)壁(bi)管(guan)焊接(jie)特別考驗焊工操(cao)作(zuo)手法(fa),焊接(jie)過程中局部(bu)停留時(shi)間(jian)稍長便容(rong)易造(zao)成焊漏(lou)。
圖3鎳(nie)基薄(bo)壁管焊接發生氧化變(bian)色
圖4鎳(nie)基薄壁管(guan)焊接附件內壁鼓包
解決辦法(fa):對于對接(jie)焊縫,采用半圈焊后冷(leng)卻降(jiang)溫再焊下半弧的焊接(jie)順(shun)序,采用斷弧焊接(jie)手(shou)法(fa)取代焊工常(chang)用連弧焊接(jie)手(shou)法(fa)可減(jian)輕(qing)鎳基管(guan)對接(jie)處母材氧化(hua)(hua),同(tong)時(shi)做(zuo)好氣體保(bao)護措施。對于附(fu)(fu)(fu)件(jian)(jian)角焊縫,通過設計優(you)化(hua)(hua)減(jian)小(xiao)附(fu)(fu)(fu)件(jian)(jian)焊腳尺寸,附(fu)(fu)(fu)件(jian)(jian)兩側用砂輪打(da)磨出倒角,減(jian)小(xiao)焊接(jie)處附(fu)(fu)(fu)件(jian)(jian)厚(hou)度,減(jian)小(xiao)焊接(jie)電流,增加(jia)焊接(jie)速度,減(jian)少熱輸入;焊接(jie)時(shi)焊接(jie)電弧偏(pian)向附(fu)(fu)(fu)件(jian)(jian)側,既保(bao)證較厚(hou)附(fu)(fu)(fu)件(jian)(jian)熔化(hua)(hua),又減(jian)少管(guan)側熱輸入,有(you)效預(yu)防(fang)管(guan)子焊漏及背部(bu)氧化(hua)(hua)。同(tong)時(shi)加(jia)強焊工考試(shi),焊前采用試(shi)樣進行(xing)焊工培訓,保(bao)證焊工具(ju)備薄(bo)壁鎳基管(guan)焊接(jie)資格(ge)。
3.3高溫吸熱涂料噴涂
吸熱(re)(re)(re)管(guan)受光部分需(xu)進(jin)(jin)行吸熱(re)(re)(re)涂(tu)(tu)(tu)(tu)(tu)(tu)(tu)料噴(pen)(pen)(pen)涂(tu)(tu)(tu)(tu)(tu)(tu)(tu),噴(pen)(pen)(pen)涂(tu)(tu)(tu)(tu)(tu)(tu)(tu)效果直接影響(xiang)吸熱(re)(re)(re)器(qi)性(xing)能(neng)指標。吸熱(re)(re)(re)涂(tu)(tu)(tu)(tu)(tu)(tu)(tu)料噴(pen)(pen)(pen)涂(tu)(tu)(tu)(tu)(tu)(tu)(tu)過程對于(yu)場地(di)環境(jing)、吸熱(re)(re)(re)管(guan)表面質量及噴(pen)(pen)(pen)涂(tu)(tu)(tu)(tu)(tu)(tu)(tu)參數都(dou)有嚴(yan)格的標準要求,由于(yu)對吸熱(re)(re)(re)涂(tu)(tu)(tu)(tu)(tu)(tu)(tu)層噴(pen)(pen)(pen)涂(tu)(tu)(tu)(tu)(tu)(tu)(tu)尚無(wu)實際生產(chan)經驗(yan),同(tong)時(shi)吸熱(re)(re)(re)管(guan)壁薄(bo)且尺寸較長,在(zai)噴(pen)(pen)(pen)涂(tu)(tu)(tu)(tu)(tu)(tu)(tu)前(qian)表面預處理過程中(zhong)吸熱(re)(re)(re)管(guan)易發生變形,吸熱(re)(re)(re)涂(tu)(tu)(tu)(tu)(tu)(tu)(tu)料噴(pen)(pen)(pen)涂(tu)(tu)(tu)(tu)(tu)(tu)(tu)質量難以保證。進(jin)(jin)爐(lu)固(gu)化前(qian)漆膜不(bu)能(neng)完全干燥存在(zai)一(yi)定粘性(xing),噴(pen)(pen)(pen)涂(tu)(tu)(tu)(tu)(tu)(tu)(tu)后(hou)(hou)需(xu)對漆膜做(zuo)好防護防止沾染灰塵等造(zao)成污染,影響(xiang)漆膜性(xing)能(neng);涂(tu)(tu)(tu)(tu)(tu)(tu)(tu)料噴(pen)(pen)(pen)涂(tu)(tu)(tu)(tu)(tu)(tu)(tu)后(hou)(hou)漆膜很(hen)薄(bo),磕碰后(hou)(hou)易產(chan)生破(po)損,需(xu)對噴(pen)(pen)(pen)涂(tu)(tu)(tu)(tu)(tu)(tu)(tu)后(hou)(hou)漆膜進(jin)(jin)行防護。
解決辦法:為保(bao)證吸熱(re)涂(tu)(tu)(tu)(tu)(tu)料噴(pen)(pen)(pen)(pen)涂(tu)(tu)(tu)(tu)(tu)效果,同時(shi)最大限度保(bao)護(hu)(hu)(hu)噴(pen)(pen)(pen)(pen)涂(tu)(tu)(tu)(tu)(tu)后漆(qi)膜(mo),制(zhi)定合理(li)的(de)噴(pen)(pen)(pen)(pen)涂(tu)(tu)(tu)(tu)(tu)流(liu)程:直管噴(pen)(pen)(pen)(pen)砂(sha)前除油→噴(pen)(pen)(pen)(pen)砂(sha)→管屏(ping)總(zong)(zong)裝→吸熱(re)涂(tu)(tu)(tu)(tu)(tu)料噴(pen)(pen)(pen)(pen)涂(tu)(tu)(tu)(tu)(tu)→常溫(wen)干燥→高溫(wen)固化(hua);采用轉運工裝架用于(yu)除油、噴(pen)(pen)(pen)(pen)砂(sha)過程吸熱(re)管轉運,防(fang)(fang)止吸熱(re)管損傷、污(wu)染(ran);噴(pen)(pen)(pen)(pen)砂(sha)后用塑料保(bao)護(hu)(hu)(hu)套包(bao)裹吸熱(re)管表面(mian),以防(fang)(fang)總(zong)(zong)裝過程污(wu)染(ran)吸熱(re)管表面(mian);對(dui)噴(pen)(pen)(pen)(pen)涂(tu)(tu)(tu)(tu)(tu)場地及設備進行修整,使(shi)其滿足噴(pen)(pen)(pen)(pen)涂(tu)(tu)(tu)(tu)(tu)標(biao)準(zhun)要求;噴(pen)(pen)(pen)(pen)涂(tu)(tu)(tu)(tu)(tu)前對(dui)施工噴(pen)(pen)(pen)(pen)涂(tu)(tu)(tu)(tu)(tu)人員進行理(li)論及現場培訓,保(bao)證作業人員具備噴(pen)(pen)(pen)(pen)涂(tu)(tu)(tu)(tu)(tu)資格;整屏(ping)噴(pen)(pen)(pen)(pen)涂(tu)(tu)(tu)(tu)(tu)后采用防(fang)(fang)護(hu)(hu)(hu)蓋防(fang)(fang)護(hu)(hu)(hu)管屏(ping),防(fang)(fang)止噴(pen)(pen)(pen)(pen)涂(tu)(tu)(tu)(tu)(tu)后及進爐高溫(wen)固化(hua)時(shi)污(wu)染(ran)漆(qi)膜(mo);針對(dui)吸熱(re)涂(tu)(tu)(tu)(tu)(tu)層噴(pen)(pen)(pen)(pen)涂(tu)(tu)(tu)(tu)(tu)無實(shi)際生產(chan)經驗的(de)問題,在產(chan)前進行噴(pen)(pen)(pen)(pen)涂(tu)(tu)(tu)(tu)(tu)全流(liu)程模擬(ni)件制(zhi)造,驗證噴(pen)(pen)(pen)(pen)涂(tu)(tu)(tu)(tu)(tu)方(fang)案的(de)可實(shi)施性,噴(pen)(pen)(pen)(pen)涂(tu)(tu)(tu)(tu)(tu)模擬(ni)件見(jian)圖5。
3.4制造過程防護控制
吸熱(re)管(guan)壁厚(hou)非常薄且單根吸熱(re)管(guan)總(zong)長較長,生產、吊運過程(cheng)中極易(yi)(yi)導致管(guan)子(zi)變形,若發生磕(ke)碰(peng)極易(yi)(yi)產生凹坑;吸熱(re)管(guan)受光部分(fen)需(xu)噴(pen)(pen)涂(tu)吸熱(re)涂(tu)料,噴(pen)(pen)涂(tu)流程(cheng)較為復雜,需(xu)經歷多道表面處(chu)理工(gong)序,涂(tu)料噴(pen)(pen)涂(tu)全程(cheng)及噴(pen)(pen)涂(tu)完成后,產品表面均禁(jin)止磕(ke)碰(peng)和其它異物污染;吸熱(re)管(guan)受光區域管(guan)子(zi)不允(yun)許拼(pin)接,局部損傷(shang)后整根管(guan)子(zi)均不能使用,無法返修;針對上述情況(kuang),吸熱(re)器制(zhi)(zhi)造過程(cheng)防護控(kong)制(zhi)(zhi)非常重要。
圖5吸熱涂(tu)料(liao)噴涂(tu)模擬件
解決辦法:針(zhen)對吸(xi)熱器(qi)制(zhi)造(zao)過(guo)程(cheng)(cheng)防護(hu)控制(zhi),提出(chu)詳(xiang)細的(de)防護(hu)要求,如吸(xi)熱管采用(yong)(yong)(yong)人(ren)工(gong)(gong)搬運的(de)方式,不(bu)允許使用(yong)(yong)(yong)吊(diao)車起吊(diao),管子轉運采用(yong)(yong)(yong)轉運工(gong)(gong)裝(zhuang)架(jia),防止(zhi)管子變形(xing)、劃傷(shang)等;吸(xi)熱管裝(zhuang)焊所用(yong)(yong)(yong)料(liao)架(jia),均采用(yong)(yong)(yong)膠皮(pi)進行(xing)支(zhi)墊(dian),防止(zhi)磕碰吸(xi)熱管表(biao)面;油(you)漆后的(de)管屏,需采用(yong)(yong)(yong)專用(yong)(yong)(yong)工(gong)(gong)裝(zhuang)架(jia)進行(xing)起吊(diao)、轉運,并采用(yong)(yong)(yong)防護(hu)工(gong)(gong)裝(zhuang)進行(xing)防護(hu),防止(zhi)吸(xi)熱管表(biao)面漆膜損(sun)傷(shang)、污(wu)染等。詳(xiang)細梳理制(zhi)造(zao)過(guo)程(cheng)(cheng)防護(hu)控制(zhi)要點,編制(zhi)專門(men)(men)的(de)制(zhi)造(zao)工(gong)(gong)藝(yi)(yi)規程(cheng)(cheng)下發(fa)至相關部門(men)(men),并對相關人(ren)員進行(xing)工(gong)(gong)藝(yi)(yi)技術(shu)交底及培訓。
4結束語
通過對塔式光熱發(fa)電(dian)(dian)吸(xi)熱器(qi)制造工藝技術的(de)(de)研究,采用正確的(de)(de)工藝措施,保(bao)(bao)證(zheng)產品的(de)(de)冷(leng)作、焊接、噴涂(tu)、裝配質量,總結出塔式光熱發(fa)電(dian)(dian)吸(xi)熱器(qi)的(de)(de)相關制造工藝技術,結合我(wo)公司(si)的(de)(de)設(she)備及生產能(neng)力(li),制定(ding)合理的(de)(de)工藝方案,在保(bao)(bao)證(zheng)產品順利生產的(de)(de)同(tong)時,為后(hou)續同(tong)類(lei)產品的(de)(de)制造積累經驗(yan),對我(wo)公司(si)后(hou)續光熱項目的(de)(de)簽訂(ding)具(ju)有(you)重要意義。
本文(wen)轉自《鍋爐制造》,作者:王靜,康寶龍,宋建。