熱水(shui)(shui)(shui)供應系(xi)統的安裝(zhuang)(zhuang)(zhuang)技術(shu)要求與(yu)熱水(shui)(shui)(shui)采暖(nuan)系(xi)統安裝(zhuang)(zhuang)(zhuang)技術(shu)要求相同。用水(shui)(shui)(shui)點(又稱(cheng)配水(shui)(shui)(shui)點)多為(wei)衛(wei)生(sheng)設(she)備,安裝(zhuang)(zhuang)(zhuang)要求見給、排水(shui)(shui)(shui)、衛(wei)生(sheng)設(she)備安裝(zhuang)(zhuang)(zhuang)相關部分。


 熱水(shui)(shui)供應(ying)系統所(suo)(suo)需(xu)設備如(ru)圖2-52所(suo)(suo)示,主要有循環水(shui)(shui)泵(beng)、補充(chong)水(shui)(shui)泵(beng)、冷水(shui)(shui)箱、閉式膨脹水(shui)(shui)箱、自動排氣閥、安全閥、水(shui)(shui)的(de)加(jia)熱裝置等(deng)。


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  冷水(shui)(shui)(shui)(shui)箱可(ke)以(yi)采(cai)(cai)用(yong)(yong)熱(re)(re)水(shui)(shui)(shui)(shui)采(cai)(cai)暖中(zhong)的膨(peng)脹(zhang)水(shui)(shui)(shui)(shui)箱,并且還可(ke)斟情省略一些管道,設(she)計和施工中(zhong)可(ke)采(cai)(cai)用(yong)(yong)國際中(zhong)有(you)關水(shui)(shui)(shui)(shui)箱標準圖(tu)。閉式膨(peng)脹(zhang)水(shui)(shui)(shui)(shui)箱完全可(ke)以(yi)采(cai)(cai)用(yong)(yong)熱(re)(re)水(shui)(shui)(shui)(shui)采(cai)(cai)暖系(xi)統(tong)(tong)中(zhong)低(di)位(wei)膨(peng)脹(zhang)水(shui)(shui)(shui)(shui)箱,該裝置接人系(xi)統(tong)(tong)后如圖(tu)2-52(b)所示,啟動(dong)補水(shui)(shui)(shui)(shui)泵(beng)(beng)(beng)(beng),水(shui)(shui)(shui)(shui)被送(song)(song)(song)入(ru)管網時,也同時送(song)(song)(song)入(ru)罐體(ti)膠(jiao)(jiao)(jiao)(jiao)囊(nang)(nang)(nang)內,在運(yun)行壓(ya)(ya)(ya)力(li)(li)較低(di)時(即系(xi)統(tong)(tong)用(yong)(yong)水(shui)(shui)(shui)(shui)較多、水(shui)(shui)(shui)(shui)位(wei)下降),補水(shui)(shui)(shui)(shui)泵(beng)(beng)(beng)(beng)把水(shui)(shui)(shui)(shui)不(bu)斷(duan)送(song)(song)(song)入(ru)系(xi)統(tong)(tong)并送(song)(song)(song)入(ru)膠(jiao)(jiao)(jiao)(jiao)囊(nang)(nang)(nang)內,膠(jiao)(jiao)(jiao)(jiao)囊(nang)(nang)(nang)不(bu)斷(duan)向外(wai)擴大而(er)擠壓(ya)(ya)(ya)氣(qi)(qi)(qi)室(shi),氣(qi)(qi)(qi)室(shi)的縮小(xiao)使(shi)壓(ya)(ya)(ya)力(li)(li)升高(gao),當壓(ya)(ya)(ya)力(li)(li)達到設(she)計最高(gao)壓(ya)(ya)(ya)力(li)(li)時,膠(jiao)(jiao)(jiao)(jiao)囊(nang)(nang)(nang)內的容水(shui)(shui)(shui)(shui)量達到設(she)計值,此時膠(jiao)(jiao)(jiao)(jiao)囊(nang)(nang)(nang)內外(wai)壓(ya)(ya)(ya)力(li)(li)相等,膠(jiao)(jiao)(jiao)(jiao)囊(nang)(nang)(nang)不(bu)脹(zhang)不(bu)縮,處于暫(zan)時平衡狀態(tai)。補水(shui)(shui)(shui)(shui)泵(beng)(beng)(beng)(beng)通(tong)過(guo)壓(ya)(ya)(ya)力(li)(li)控制(zhi)器而(er)停(ting)運(yun)。水(shui)(shui)(shui)(shui)泵(beng)(beng)(beng)(beng)停(ting)運(yun)后,氣(qi)(qi)(qi)室(shi)中(zhong)氣(qi)(qi)(qi)體(ti)壓(ya)(ya)(ya)力(li)(li)擠壓(ya)(ya)(ya)膠(jiao)(jiao)(jiao)(jiao)囊(nang)(nang)(nang),使(shi)膠(jiao)(jiao)(jiao)(jiao)囊(nang)(nang)(nang)內的水(shui)(shui)(shui)(shui)流人系(xi)統(tong)(tong),氣(qi)(qi)(qi)室(shi)壓(ya)(ya)(ya)力(li)(li)也隨(sui)之減小(xiao),當氣(qi)(qi)(qi)壓(ya)(ya)(ya)降到設(she)計最低(di)壓(ya)(ya)(ya)力(li)(li)時,通(tong)過(guo)壓(ya)(ya)(ya)力(li)(li)控制(zhi)器啟動(dong)水(shui)(shui)(shui)(shui)泵(beng)(beng)(beng)(beng),又(you)(you)使(shi)水(shui)(shui)(shui)(shui)送(song)(song)(song)進系(xi)統(tong)(tong)和膠(jiao)(jiao)(jiao)(jiao)囊(nang)(nang)(nang),這就既保(bao)證了用(yong)(yong)戶供(gong)(gong)熱(re)(re)水(shui)(shui)(shui)(shui)(或(huo)供(gong)(gong)冷水(shui)(shui)(shui)(shui))的需要,又(you)(you)使(shi)水(shui)(shui)(shui)(shui)泵(beng)(beng)(beng)(beng)有(you)條件地間斷(duan)工作,節約了電能。目(mu)前已(yi)成為熱(re)(re)水(shui)(shui)(shui)(shui)供(gong)(gong)應系(xi)統(tong)(tong)或(huo)無塔(ta)供(gong)(gong)水(shui)(shui)(shui)(shui)的常用(yong)(yong)設(she)備。其規格見(jian)表2-24。


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 水(shui)(shui)(shui)的(de)加熱設備是熱水(shui)(shui)(shui)供應的(de)熱源部分,又稱加熱器(qi)(qi)。根據系統(tong)范圍大小可采用(yong)水(shui)(shui)(shui)-水(shui)(shui)(shui)熱交(jiao)換器(qi)(qi)、汽(qi)一水(shui)(shui)(shui)熱交(jiao)換器(qi)(qi)、電熱水(shui)(shui)(shui)器(qi)(qi)、燃氣熱水(shui)(shui)(shui)器(qi)(qi)、太陽能熱水(shui)(shui)(shui)器(qi)(qi)等多種。如要(yao)(yao)求這些熱水(shui)(shui)(shui)器(qi)(qi)不僅起加熱作用(yong),還(huan)要(yao)(yao)有(you)(you)貯存和調節水(shui)(shui)(shui)量的(de)功(gong)能,就(jiu)必須(xu)有(you)(you)一定的(de)盛水(shui)(shui)(shui)體(ti)積,這種加熱器(qi)(qi)稱為容(rong)積式,對于只起加熱稱為快速式。


 容積式(shi)加(jia)(jia)熱器的結(jie)構(gou)如圖(tu)2-52所(suo)示,由罐(guan)體(ti)、盤管(guan)等組成(cheng)。盤管(guan)內送人高溫熱水或(huo)(huo)蒸(zheng)汽(qi),將(jiang)熱量(liang)通(tong)過盤管(guan)表面(mian)積傳給冷(leng)水。罐(guan)體(ti)由支座直接(jie)用(yong)(yong)地(di)腳螺栓固定在(zai)地(di)基上,高溫熱水或(huo)(huo)蒸(zheng)汽(qi)通(tong)過管(guan)道(dao)與加(jia)(jia)熱器相連接(jie)。采用(yong)(yong)蒸(zheng)汽(qi)加(jia)(jia)熱時其蒸(zheng)汽(qi)凝結(jie)水出口還(huan)要連接(jie)疏水閥等附件(jian)。


 板式換熱器是應用最多的非容積式加熱器,廣泛用于采暖和熱水供應的換熱上。板式換熱器的結構為框架式,如圖2-53所示。框架由固定壓緊板、上導梁、下導梁和支柱組成。活動壓緊板通過滾輪懸掛在上導梁上,傳熱板片置于固定壓緊板與活動壓緊板之間,大型板式換熱器的傳熱片是用掛鉤掛在上導梁上,上部卡在下導梁上。傳熱板是用0.8mm厚的不銹(xiu)鋼板壓制成雙人字形波紋板片,四角沖制圓孔洞。板片四周及圓孔處均鑲嵌有密封橡膠墊起密封作用。組裝時傳熱板片相互倒置排列,使傳熱板片上波紋的波峰與波峰間互相接觸形成網狀流道,既強化了傳熱又增加了傳熱板的剛度,同時提高了板式換熱器的承壓能力。傳熱板通過夾緊螺栓,并按照組裝尺寸要求(或傳熱面積一片數),夾緊固定壓緊板和活動壓緊板之間。固定壓緊板和活動壓緊板的四角根據工藝的需要均設孔洞,并裝有與外部管道連接用的帶法蘭的短管,與傳熱片組裝在一起,構成了供冷熱介質流動的通道。圖2-54給出了傳熱板片并聯流程組合流程圖,每兩張傳熱板片間就構成一個流道,冷熱介質交替地流過傳熱板片,同時熱量通過傳熱板片由熱介質傳給了冷介質。由于雙人字形傳熱板片的結構特性所決定,介質在傳熱板片流動時,在低流速下即可激發湍流,使冷熱介質進行強烈地熱交換,因此板式換熱器與其他換熱器相比,具有較高的傳熱系數。根據冷介質的出口溫度要求,流程可以組成串聯、并聯、混合等多種形式,在設計時提出要求,生產企業按要求進行組裝供貨。


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 板式(shi)換熱(re)器豎直地用地腳螺栓固(gu)定在(zai)混凝土地坪上,四周(zhou)留有一定距(ju)離,以便于(yu)管道、附(fu)件的(de)安裝及設備的(de)檢修。換熱(re)器使用前應對(dui)熱(re)側(ce)、冷(leng)側(ce)分別進(jin)行水壓(ya)試(shi)驗,其試(shi)驗壓(ya)力(li)為設計壓(ya)力(li)的(de)1.25倍,并保(bao)壓(ya)20min,確(que)認各密封部位無滲漏后方可投入使用。


 在作采暖時,循環(huan)水進出口均裝壓力表,在使(shi)用(yong)(yong)中若壓降增大說明內部(bu)產(chan)生結垢淤塞,此時應(ying)松開(kai)夾緊(jin)螺栓,移(yi)動活動壓緊(jin)板,然后進行清洗。清洗板片(pian)時要(yao)用(yong)(yong)棕刷,切勿用(yong)(yong)鋼絲刷,以免劃傷板片(pian)和橡膠墊。損壞的(de)板片(pian)要(yao)更(geng)換(huan),若沒有備用(yong)(yong)板片(pian),可(ke)拆下兩個相鄰(lin)的(de)板片(pian),然后夾緊(jin)使(shi)用(yong)(yong)。


 特別提醒:老化的(de)密(mi)(mi)封(feng)橡膠墊要及時更新,要把板片(pian)的(de)密(mi)(mi)封(feng)槽清洗干凈后涂粘結劑,再把密(mi)(mi)封(feng)膠墊鑲嵌在密(mi)(mi)封(feng)槽內。


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 在實際工程中,使用蒸汽直接與冷水混合產生熱水的方法也比較普遍,這種方法簡單、投資小、維修方便,但噪聲大,冷凝水不能回收利用。常用的方法有多孔管放在水箱內,送入蒸汽,蒸汽從小孔中噴出與水混合,也可采用專用的汽水混合加熱器,其構造如圖2-55所示。在外殼內裝有錐形管,管壁上布滿小孔,冷水在流動中與蒸汽在錐形管內混合,適用于具有蒸汽熱源的熱水采暖系統與熱水供應系統,同時隨熱負荷的改變,調整蒸汽閥門的開啟度即可實現溫度調節。該國標圖集供、回水溫差大小分為25℃、40℃、60℃三種型號按噴管喉口直徑大小分為6、8、10、12、14、16、18、20、25、30、35、40、50、60、70(mm)共15個型號。供熱水和采暖系統管道連接方式如圖2-56、圖2-57所示。為防止供水溫度過熱,在蒸汽管道入口設置溫度自動控制系統,如安裝自力式溫度調節閥。為防止系統水倒灌入蒸汽系統中,在蒸汽管路上安裝逆止閥(fa)



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