熱水供應系(xi)統(tong)的安(an)裝(zhuang)(zhuang)技術要求與(yu)熱水采暖(nuan)系(xi)統(tong)安(an)裝(zhuang)(zhuang)技術要求相同。用水點(又稱(cheng)配水點)多為衛(wei)生(sheng)設(she)備(bei)(bei),安(an)裝(zhuang)(zhuang)要求見給、排水、衛(wei)生(sheng)設(she)備(bei)(bei)安(an)裝(zhuang)(zhuang)相關部分。


 熱水(shui)供應系統(tong)所需設備如圖2-52所示,主(zhu)要有循環水(shui)泵、補充(chong)水(shui)泵、冷水(shui)箱、閉式膨脹水(shui)箱、自(zi)動排(pai)氣閥、安全閥、水(shui)的加熱裝置等。


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  冷(leng)水(shui)(shui)(shui)(shui)(shui)(shui)箱(xiang)(xiang)(xiang)可以采用(yong)(yong)(yong)熱水(shui)(shui)(shui)(shui)(shui)(shui)采暖中的(de)(de)膨脹(zhang)水(shui)(shui)(shui)(shui)(shui)(shui)箱(xiang)(xiang)(xiang),并且還可斟(zhen)情省略一(yi)些管道(dao),設(she)計和(he)施(shi)工中可采用(yong)(yong)(yong)國際中有(you)(you)關水(shui)(shui)(shui)(shui)(shui)(shui)箱(xiang)(xiang)(xiang)標準(zhun)圖。閉式膨脹(zhang)水(shui)(shui)(shui)(shui)(shui)(shui)箱(xiang)(xiang)(xiang)完全可以采用(yong)(yong)(yong)熱水(shui)(shui)(shui)(shui)(shui)(shui)采暖系統(tong)(tong)中低(di)位(wei)膨脹(zhang)水(shui)(shui)(shui)(shui)(shui)(shui)箱(xiang)(xiang)(xiang),該(gai)裝置接人系統(tong)(tong)后如圖2-52(b)所示,啟(qi)動補(bu)(bu)水(shui)(shui)(shui)(shui)(shui)(shui)泵(beng),水(shui)(shui)(shui)(shui)(shui)(shui)被送(song)(song)入(ru)管網時(shi),也同時(shi)送(song)(song)入(ru)罐體膠(jiao)囊(nang)內(nei)(nei),在運(yun)行(xing)壓(ya)(ya)力(li)(li)較(jiao)低(di)時(shi)(即(ji)系統(tong)(tong)用(yong)(yong)(yong)水(shui)(shui)(shui)(shui)(shui)(shui)較(jiao)多、水(shui)(shui)(shui)(shui)(shui)(shui)位(wei)下降),補(bu)(bu)水(shui)(shui)(shui)(shui)(shui)(shui)泵(beng)把水(shui)(shui)(shui)(shui)(shui)(shui)不斷送(song)(song)入(ru)系統(tong)(tong)并送(song)(song)入(ru)膠(jiao)囊(nang)內(nei)(nei),膠(jiao)囊(nang)不斷向外擴大而擠(ji)(ji)壓(ya)(ya)氣(qi)室(shi),氣(qi)室(shi)的(de)(de)縮(suo)小使(shi)(shi)壓(ya)(ya)力(li)(li)升高,當(dang)(dang)壓(ya)(ya)力(li)(li)達(da)到設(she)計最高壓(ya)(ya)力(li)(li)時(shi),膠(jiao)囊(nang)內(nei)(nei)的(de)(de)容水(shui)(shui)(shui)(shui)(shui)(shui)量達(da)到設(she)計值(zhi),此(ci)時(shi)膠(jiao)囊(nang)內(nei)(nei)外壓(ya)(ya)力(li)(li)相等,膠(jiao)囊(nang)不脹(zhang)不縮(suo),處于暫時(shi)平衡狀(zhuang)態(tai)。補(bu)(bu)水(shui)(shui)(shui)(shui)(shui)(shui)泵(beng)通(tong)過(guo)壓(ya)(ya)力(li)(li)控(kong)制器(qi)而停(ting)運(yun)。水(shui)(shui)(shui)(shui)(shui)(shui)泵(beng)停(ting)運(yun)后,氣(qi)室(shi)中氣(qi)體壓(ya)(ya)力(li)(li)擠(ji)(ji)壓(ya)(ya)膠(jiao)囊(nang),使(shi)(shi)膠(jiao)囊(nang)內(nei)(nei)的(de)(de)水(shui)(shui)(shui)(shui)(shui)(shui)流人系統(tong)(tong),氣(qi)室(shi)壓(ya)(ya)力(li)(li)也隨之減小,當(dang)(dang)氣(qi)壓(ya)(ya)降到設(she)計最低(di)壓(ya)(ya)力(li)(li)時(shi),通(tong)過(guo)壓(ya)(ya)力(li)(li)控(kong)制器(qi)啟(qi)動水(shui)(shui)(shui)(shui)(shui)(shui)泵(beng),又使(shi)(shi)水(shui)(shui)(shui)(shui)(shui)(shui)送(song)(song)進系統(tong)(tong)和(he)膠(jiao)囊(nang),這就既保(bao)證(zheng)了用(yong)(yong)(yong)戶供(gong)熱水(shui)(shui)(shui)(shui)(shui)(shui)(或供(gong)冷(leng)水(shui)(shui)(shui)(shui)(shui)(shui))的(de)(de)需要,又使(shi)(shi)水(shui)(shui)(shui)(shui)(shui)(shui)泵(beng)有(you)(you)條件地間斷工作,節約了電(dian)能。目前(qian)已成為(wei)熱水(shui)(shui)(shui)(shui)(shui)(shui)供(gong)應系統(tong)(tong)或無塔(ta)供(gong)水(shui)(shui)(shui)(shui)(shui)(shui)的(de)(de)常用(yong)(yong)(yong)設(she)備。其規格見表(biao)2-24。


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 水(shui)(shui)(shui)(shui)的(de)加(jia)(jia)熱(re)設備是熱(re)水(shui)(shui)(shui)(shui)供應的(de)熱(re)源部分,又稱(cheng)加(jia)(jia)熱(re)器(qi)(qi)(qi)。根據系統范圍大小可采用(yong)(yong)水(shui)(shui)(shui)(shui)-水(shui)(shui)(shui)(shui)熱(re)交(jiao)換器(qi)(qi)(qi)、汽一水(shui)(shui)(shui)(shui)熱(re)交(jiao)換器(qi)(qi)(qi)、電熱(re)水(shui)(shui)(shui)(shui)器(qi)(qi)(qi)、燃(ran)氣熱(re)水(shui)(shui)(shui)(shui)器(qi)(qi)(qi)、太陽能熱(re)水(shui)(shui)(shui)(shui)器(qi)(qi)(qi)等多種。如要求這些熱(re)水(shui)(shui)(shui)(shui)器(qi)(qi)(qi)不僅起加(jia)(jia)熱(re)作用(yong)(yong),還要有貯存和調節水(shui)(shui)(shui)(shui)量的(de)功能,就必(bi)須有一定的(de)盛水(shui)(shui)(shui)(shui)體積,這種加(jia)(jia)熱(re)器(qi)(qi)(qi)稱(cheng)為容積式,對(dui)于只起加(jia)(jia)熱(re)稱(cheng)為快速(su)式。


 容積式加(jia)熱(re)(re)(re)(re)(re)器(qi)的結構(gou)如圖2-52所示,由罐體、盤管等(deng)組(zu)成。盤管內送人(ren)高溫(wen)熱(re)(re)(re)(re)(re)水(shui)或蒸(zheng)汽(qi),將熱(re)(re)(re)(re)(re)量通(tong)過盤管表面(mian)積傳給冷水(shui)。罐體由支(zhi)座直接用地(di)腳螺(luo)栓固(gu)定在(zai)地(di)基上(shang),高溫(wen)熱(re)(re)(re)(re)(re)水(shui)或蒸(zheng)汽(qi)通(tong)過管道(dao)與加(jia)熱(re)(re)(re)(re)(re)器(qi)相連接。采用蒸(zheng)汽(qi)加(jia)熱(re)(re)(re)(re)(re)時(shi)其蒸(zheng)汽(qi)凝結水(shui)出口(kou)還要連接疏水(shui)閥等(deng)附件。


 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厚的不銹鋼(gang)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(ban)式換(huan)熱器豎直地用(yong)地腳螺栓(shuan)固定在混(hun)凝土地坪上,四周(zhou)留有一定距離,以便于管道、附(fu)件(jian)的(de)(de)安(an)裝及設備(bei)的(de)(de)檢修。換(huan)熱器使用(yong)前應對熱側、冷側分別(bie)進行水壓試驗(yan),其試驗(yan)壓力為設計壓力的(de)(de)1.25倍,并保壓20min,確(que)認各密封(feng)部位無滲漏后方可(ke)投入使用(yong)。


 在作采(cai)暖時,循環水(shui)進出口均裝壓力表(biao),在使(shi)(shi)用中若壓降增大說明內部(bu)產生結垢淤塞(sai),此時應松開夾(jia)緊(jin)螺栓,移動活(huo)動壓緊(jin)板,然(ran)后(hou)進行(xing)清洗。清洗板片(pian)時要用棕刷,切勿用鋼絲刷,以免劃傷(shang)板片(pian)和橡膠墊(dian)。損壞的(de)板片(pian)要更換(huan),若沒有(you)備(bei)用板片(pian),可拆下(xia)兩個相鄰的(de)板片(pian),然(ran)后(hou)夾(jia)緊(jin)使(shi)(shi)用。


 特(te)別提醒:老(lao)化的密(mi)封(feng)橡膠墊要(yao)及時更(geng)新(xin),要(yao)把板片的密(mi)封(feng)槽清洗干(gan)凈后涂粘結劑,再(zai)把密(mi)封(feng)膠墊鑲嵌在密(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(jie)閥(fa)。為防止系統水倒灌入蒸汽系統中,在蒸汽管路上安裝逆止(zhi)閥



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