上海某辦公樓給排水系統(tǒng)畢業(yè)設(shè)計(jì)
上海某辦公樓給排水系統(tǒng)畢業(yè)設(shè)計(jì),上海,辦公樓,排水系統(tǒng),畢業(yè)設(shè)計(jì)
上海XXXX學(xué)院土木與建筑工程系畢業(yè)設(shè)計(jì)開題報(bào)告 課題名稱:上海某辦公樓給排水系統(tǒng)設(shè)計(jì) 專業(yè):建筑環(huán)境與設(shè)備工程 班級:XXXXXXX 姓名:XX 導(dǎo)師:XXX1課題名稱:上海某辦公樓給排水系統(tǒng)設(shè)計(jì)2課題研究背景給水排水工程是現(xiàn)代化城市基礎(chǔ)設(shè)施建設(shè)與工業(yè)企業(yè)建設(shè)的重要組成部分之一,它的建設(shè)與發(fā)展直接關(guān)系到城市(鎮(zhèn))居民的生活水平、生活質(zhì)量的提高與工業(yè)企業(yè)規(guī)模的擴(kuò)大與發(fā)展,但同時(shí)也受到當(dāng)?shù)刈匀毁Y源狀況、經(jīng)濟(jì)發(fā)展水平、文化背景與發(fā)展歷史的限制。隨著我國城市化步伐的加速和工業(yè)經(jīng)濟(jì)的發(fā)展,城市居民生活用水和工業(yè)企業(yè)用水需求量日益增加,對用水水質(zhì)的要求也日益嚴(yán)格。但是,我國是一個(gè)人均水資源量十分貧乏的國家,目前嚴(yán)重的水污染使得部分水體喪失原有功能,更加劇了水資源的緊張局面,缺水已成為城市與工業(yè)發(fā)展最為重要的限制條件之一,有效利用現(xiàn)有的有限水資源成為擺在給水排水工程技術(shù)人員面前的一個(gè)重要而緊迫的課題。3課題的意義畢業(yè)設(shè)計(jì)是高等院校培養(yǎng)具有創(chuàng)新精神和實(shí)踐能力的高級專業(yè)人才不可缺少的重要實(shí)踐教學(xué)環(huán)節(jié),是教學(xué)計(jì)劃的重要組成部分,是對我們學(xué)生進(jìn)行綜合訓(xùn)練的重要階段。通過畢業(yè)設(shè)計(jì),能夠培養(yǎng)我們綜合運(yùn)用專業(yè)知識及相關(guān)知識的能力和工程實(shí)踐能力,在指導(dǎo)教師的幫助下,在查閱中外文獻(xiàn)、資料收集及調(diào)查研究、計(jì)算機(jī)編程及應(yīng)用、工程設(shè)計(jì)及圖紙繪制、設(shè)計(jì)計(jì)算說明書的撰寫等方面的能力得到一定程度的提高,進(jìn)而提高適應(yīng)實(shí)際工作需要的能力。工程設(shè)計(jì)是對擬建工程的實(shí)施在技術(shù)和經(jīng)濟(jì)上所進(jìn)行的全面而詳盡的安排,是聯(lián)系項(xiàng)目決策與工程實(shí)體的橋梁,是工程建設(shè)最為重要的階段。建筑給排水系統(tǒng)的設(shè)計(jì)看似簡單,但它與我們的日常生活息息相關(guān)。作為工程設(shè)計(jì)人員,應(yīng)本著技術(shù)、安全、經(jīng)濟(jì)性原則,在實(shí)踐中努力創(chuàng)新,尋求最佳的給排水設(shè)計(jì)方案,適應(yīng)建筑設(shè)計(jì)發(fā)展的新要求,滿足不同的使用要求。通過設(shè)計(jì)訓(xùn)練,我們不僅要學(xué)會工程設(shè)計(jì)的基本方法,也要學(xué)會運(yùn)用工程經(jīng)濟(jì)思想綜合解決工程問題。同時(shí),通過畢業(yè)設(shè)計(jì),我們應(yīng)樹立正確的設(shè)計(jì)思想,培養(yǎng)嚴(yán)肅認(rèn)真的科學(xué)態(tài)度和嚴(yán)謹(jǐn)求實(shí)的科學(xué)作風(fēng)。能遵守紀(jì)律,善于與他人合作和敬業(yè)精神,樹立正確的工程觀點(diǎn)、生產(chǎn)觀點(diǎn)、經(jīng)濟(jì)觀點(diǎn)和全局觀點(diǎn)。4文獻(xiàn)調(diào)研情況針對此次的畢業(yè)設(shè)計(jì),主要學(xué)習(xí)研究建筑中給水、排水系統(tǒng)及消防系統(tǒng)的設(shè)計(jì)及相關(guān)技術(shù)。4.1 我國近年建筑給排水技術(shù)情況回顧4.1.1 建筑給水建筑給水的任務(wù)是將符合水質(zhì)標(biāo)準(zhǔn)的水送至生活、生產(chǎn)和消防給水系統(tǒng)各用水點(diǎn),滿足水量和水壓的要求。這涉及到水的分配、計(jì)量、輸送、儲存和加壓以及水質(zhì)標(biāo)準(zhǔn)和防水質(zhì)污染。水的分配方面,我國已明令限期禁用普通旋啟式水龍頭,而代之以瓷片式水龍頭。瓷片式水龍頭節(jié)水,使用方便,冷熱水混合效果好,但缺點(diǎn)是水流阻力大,對系統(tǒng)的影響是:直接影響水箱設(shè)置高度和給水方式。節(jié)水技術(shù)方面光電和紅外感應(yīng)控制已從水龍頭出水控制擴(kuò)大至小便器和大便器的沖洗用水。水的輸送突出表現(xiàn)在塑料管的推廣應(yīng)用,建設(shè)部等四部委1999年12月發(fā)文:“關(guān)于在住宅建設(shè)中淘汰落后產(chǎn)品的通知”,明確2000年6月1日起在城鎮(zhèn)新建住宅中禁用使用冷鍍鋅鋼管于室內(nèi)給水管道,并根據(jù)當(dāng)?shù)貙?shí)際情況,逐步限時(shí)淘汰熱浸鍍鋅鋼管。推薦應(yīng)用鋁塑復(fù)合管、交聯(lián)聚乙烯管和三型聚丙烯管等新型管材。世界上不少發(fā)達(dá)國家早在十多年前已規(guī)定,建筑中不準(zhǔn)使用鍍鋅鋼管;香港水務(wù)局在1995年起已明確規(guī)定,新建筑中不得使用鍍鋅鋼管,舊建筑物內(nèi)原有管道亦必須限期改造;而上海也已規(guī)定,凡1998年5月1日起設(shè)計(jì)的施工圖和1998年10月1日起開工的住宅、多層住宅和多層公共建筑,其室內(nèi)的給水管道,禁止設(shè)計(jì)、使用鍍鋅鋼管,推廣使用塑料給水管。給水流量計(jì)算,在概率法計(jì)算給水設(shè)計(jì)秒流量作了有益的探索,用生活用水定額來確定用水概率已達(dá)到實(shí)用階段。管道連接除了不同材質(zhì)的給水塑料管采用相應(yīng)的接口方式外,溝槽式管接頭是一項(xiàng)重大進(jìn)展,溝槽式連接方式不破壞鍍鋅層、拆卸方便、不動用明火、施工快速、口徑運(yùn)用范圍大、耐壓值高、優(yōu)點(diǎn)突出,已成為和螺紋、法蘭、承插口連接并列的一種新的接頭方式。水的儲存方面,已經(jīng)歷了水箱的材質(zhì)改善、補(bǔ)氣式氣壓給水設(shè)備補(bǔ)氣方式改進(jìn)和隔膜式氣壓給水設(shè)備隔膜形式發(fā)展三大進(jìn)展,目前儲水裝置成為熱點(diǎn)的問題是氣壓水罐調(diào)節(jié)水量的確定和氣壓水罐的主功能探索。水質(zhì)方面,建筑給水系統(tǒng)已從單一系統(tǒng)的單一水質(zhì)標(biāo)準(zhǔn)一生活飲用水水質(zhì)標(biāo)準(zhǔn),發(fā)展為標(biāo)準(zhǔn)高的飲用凈水系統(tǒng)和標(biāo)準(zhǔn)低的雜用水系統(tǒng),多種水質(zhì)標(biāo)準(zhǔn)多種系統(tǒng)適用于各種不同用途的用水要求。防水質(zhì)污染措施管是建筑給水的薄弱環(huán)節(jié)。在現(xiàn)階段,建筑給水水質(zhì)保障技術(shù)受到高度重視,措施全面而且可行,其中防污隔斷閥的應(yīng)用更使防回流污染落到實(shí)處。4.1.2 建筑排水節(jié)水型衛(wèi)生器具重點(diǎn)推薦采用6L的沖洗水箱,在現(xiàn)階段地漏也受到關(guān)注,用于不同場合的不同型式的地漏先后得到應(yīng)用,傳統(tǒng)的鐘罩式地漏和防返溢地漏受到挑戰(zhàn),對地漏的學(xué)術(shù)討論日益深化。排水塑料管的噪聲防治,或采用改變水流狀態(tài)的方法、或采用改變管道結(jié)構(gòu)型式、或兼用兩種方式,都有一定效果。排水塑料管的推廣應(yīng)用已從以室內(nèi)為重點(diǎn),轉(zhuǎn)到側(cè)重于室外埋地排水管,加筋管、波紋管、纏繞管和玻璃鋼夾砂管用于室外埋地排水充分發(fā)揮了塑料管的材質(zhì)特性。建筑中水是污水處理回用中的一個(gè)重要環(huán)節(jié)。不少城市有關(guān)建筑中水工程的指令性規(guī)定,有利于建筑中水技術(shù)的進(jìn)展。雨水利用已列入議事日程。為緩解室外排水系統(tǒng)滿流、室內(nèi)排出管因房屋沉降而倒坡等排出管排水工況惡化問題,重力排水系統(tǒng)止回閥得到認(rèn)可。4.1.3 建筑消防建筑消防為建筑給水排水技術(shù)人員所重視。建筑消防正處于以消火栓給水系統(tǒng)為主向以自動噴水滅火系統(tǒng)為主,臨時(shí)高壓消防給水系統(tǒng)向穩(wěn)高壓消防給水系統(tǒng)發(fā)展、鹵代烷滅火系統(tǒng)向系統(tǒng)替代和鹵代烷替代物替代的轉(zhuǎn)折期。4.2 西方發(fā)達(dá)國家目前建筑給排水的一些特點(diǎn)4.2.1 衛(wèi)生間安裝的工廠化對于各類高級建筑,如豪華酒店、高級辦公樓等,大量的衛(wèi)生間和緊張的工期使其安裝的工廠化成為必要。以阿爾及利亞希爾頓豪華五星級酒店為例,在施工過程中,采用了瑞士GEBERIT公司的GIS支撐系統(tǒng)(GEBERIT INSTALLTION SYSTEM)。該系統(tǒng)為金屬支撐骨架結(jié)構(gòu),具有足夠的強(qiáng)度??梢宰鳛楠?dú)立墻,也可以依靠現(xiàn)有建筑隔墻,厚度在10cm到22cm之間。高度從1.2m到整個(gè)層高,可以根據(jù)需要調(diào)整。它的作用是通行和隱蔽管道,懸掛并固定衛(wèi)生潔具,坐便器的水箱也安裝在該隔墻里。完整的GIS系統(tǒng)包括:支撐構(gòu)件;安裝連接件;給水和排水管;面板。GEBERIT公司是世界著名的給排水材料和附件生產(chǎn)廠家,應(yīng)用該公司提供的工作軟件,我們根據(jù)衛(wèi)生間的建筑布置和詳細(xì)尺寸,作出GIS隔墻的材料下料表。拿到這些表格的工人在車間里進(jìn)行預(yù)制加工,隔墻內(nèi)的給水管和排水管的安裝也同時(shí)完成。完成后的管道預(yù)留與立管的接頭和與衛(wèi)生潔具的接口,并以GEBERIT專用的管帽或管堵作好封堵。這一過程快速簡便,還能與土建的施工交叉,很好地解決了工程工期緊迫的矛盾。一旦土建條件具備,這些預(yù)制元件就能馬上搬運(yùn)至現(xiàn)場就位,同衛(wèi)生潔具和先期完成的管道井立管連接。當(dāng)然,GIS系統(tǒng)也不可避免地存在一些問題:首先是提高了安裝的造價(jià);另外在設(shè)計(jì)方案階段就必須綜合考慮,因?yàn)镚IS系統(tǒng)的厚度會影響到衛(wèi)生間的建筑面積,給后期帶來一些協(xié)調(diào)方面的問題和變更。4.2.2 設(shè)計(jì)體現(xiàn)節(jié)水和衛(wèi)生安全發(fā)達(dá)國家在節(jié)水方面仍然走在前列,他們在城市節(jié)水的技術(shù)與管理上都有很大發(fā)展。體現(xiàn)在建筑內(nèi)生活用水的節(jié)約上,就是采用優(yōu)質(zhì)管材和連接,供給衛(wèi)生用水,減少滲漏;使用節(jié)水型設(shè)備和配件(夾氣水嘴、夾氣淋浴頭等),減少用水量;在公共區(qū)域使用全自動開關(guān)(紅外線檢測控制開關(guān)等)取代傳統(tǒng)的易造成水浪費(fèi)的機(jī)械式開關(guān),同時(shí)也減少了污染;利用污水處理和回用達(dá)到節(jié)水目的。在安全方面,目前仍在我國大量使用的金屬鍍鋅管使用年限稍長便會發(fā)生銹蝕,影響水質(zhì),危害到人的健康。而歐共體國家的法律對取自管道和設(shè)備的水都有嚴(yán)格規(guī)定,這些國家從材料和技術(shù)上進(jìn)行研究,生產(chǎn)出適用于供水系統(tǒng)的塑料管道來保證水質(zhì)符合衛(wèi)生方面的要求。這些塑料具有不導(dǎo)電的特性,是抗腐蝕的新型材料。現(xiàn)在國內(nèi)已有GEBERIT公司和其它西歐公司的相似產(chǎn)品生產(chǎn)并得到應(yīng)用,國家有關(guān)部門逐步淘汰鍍鋅管材的強(qiáng)制性法規(guī)也在醞釀之中,我們的生活飲用水質(zhì)將會不斷地得到提高。4.2.3 以人為本的宗旨和嚴(yán)格的質(zhì)量意識在設(shè)計(jì)中,工程師通過技術(shù)手段處處體現(xiàn)以人為本、為人服務(wù)的宗旨。 仍以希爾頓酒店為例,所有客房衛(wèi)生間的管道均在本層GIS隔墻中通行,在管道井內(nèi)和立管連接。避免檢修維護(hù)時(shí)到不相關(guān)的下層去,保證了入住賓客的個(gè)人私密性。也避免了因管道穿過樓板可能帶來的漏水現(xiàn)象。針對管道噪音問題,所有的主干管都采取了隔音消聲處理,為客戶創(chuàng)造了更安靜的環(huán)境等。不管是優(yōu)質(zhì)材料、設(shè)備和新技術(shù)的應(yīng)用,還是節(jié)水安全、以人為本的宗旨,都體現(xiàn)出西方工程師對工程質(zhì)量的嚴(yán)格要求。施工前,設(shè)計(jì)師制定了非常詳細(xì)的技術(shù)條款對工程的有關(guān)技術(shù)參數(shù)、材料設(shè)備和實(shí)施手段進(jìn)行了描述。施工過程中,現(xiàn)場由設(shè)計(jì)方指定的監(jiān)理根據(jù)技術(shù)條款對承包商的工作進(jìn)行監(jiān)督。承包商按照技術(shù)條款選用的設(shè)備材料都必須制成技術(shù)卡片,標(biāo)明產(chǎn)地,材質(zhì),技術(shù)指標(biāo)等,呈送設(shè)計(jì)師備案,只有經(jīng)過設(shè)計(jì)師審批通過方能用于工程當(dāng)中。設(shè)計(jì)師也定期到現(xiàn)場處理問題,監(jiān)督施工。4.2.4 其他西歐一些國家普遍采用安裝DN25自救水槍并預(yù)留DN65水龍帶接口的方法,DN65接口供消防隊(duì)員使用,不再備用大口徑水龍帶。西歐國家工程師在設(shè)計(jì)中更注重人的因素和給排水系統(tǒng)的環(huán)境與社會效益。發(fā)達(dá)國家的先進(jìn)科技支持著他們產(chǎn)品的開發(fā)和應(yīng)用,使設(shè)備的性能更趨安全、高效;衛(wèi)生潔具節(jié)水,低噪、美觀、舒適;管材和配件性能更優(yōu)越。這正是我國和發(fā)達(dá)國家的差距之所在,也是我們建筑給排水發(fā)展的大趨向。建筑給水排水技術(shù)是水工業(yè)中的一個(gè)重要分支,其發(fā)展是與社會進(jìn)步、國力增強(qiáng)密切相關(guān)的。作為建筑設(shè)備的重要組成部分,給排水系統(tǒng)設(shè)計(jì)是否合理,對今后的裝修、日常使用與維護(hù)將產(chǎn)生重要影響。因此作為一名設(shè)計(jì)人員,在進(jìn)行工程設(shè)計(jì)時(shí)應(yīng)當(dāng)綜合考慮各方面因素,以尋求最佳的設(shè)計(jì)方案。我認(rèn)為我國今后的建筑給排水技術(shù)的發(fā)展,應(yīng)當(dāng)以兩點(diǎn)為核心:以人為本、節(jié)約用水。通過對阿爾及利亞希爾頓豪華酒店的給排水系統(tǒng)工程的了解,可以看到在“以人為本”方面,我國與發(fā)達(dá)國家仍存在著差距。我們完全可以借鑒國外先進(jìn)的技術(shù)的同時(shí)結(jié)合我國的國情,根據(jù)工程的具體情況,采用不同的技術(shù)手段來達(dá)到“以人為本”,并逐步趕上發(fā)達(dá)國家的水平?!肮?jié)水”更是一個(gè)全球性的話題。隨著人民生活質(zhì)量的提高,對供水量和質(zhì)的要求正不斷擴(kuò)展,同時(shí)實(shí)施水的可持續(xù)利用和保護(hù),使水資源不受破壞,并能進(jìn)入良性的水質(zhì)、水量再生循環(huán),也已成為政府和廣大人民群眾關(guān)注的焦點(diǎn)。這一切都給建筑給排水工程的設(shè)計(jì)提出了許多新的要求,供水技術(shù)先進(jìn)化的步伐急待加快。而目前節(jié)水最關(guān)鍵的是人們節(jié)水的意識,人們的用水習(xí)慣。據(jù)調(diào)查目前這種觀念尚未真正有效樹立。應(yīng)倡導(dǎo)人們將淡水資源當(dāng)作一種珍稀資源,節(jié)制使用,呼吁全民節(jié)水。而我們也應(yīng)當(dāng)在節(jié)水技術(shù)上不斷探索、研究,以期取得更好的節(jié)水效果。5設(shè)計(jì)主要內(nèi)容本課題要求根據(jù)所給建筑圖圖紙及圖紙中各房間的用途,對該辦公樓進(jìn)行給排水系統(tǒng)設(shè)計(jì),從而保證辦公設(shè)施使用人員的正常工作生活。5.1 建筑給水系統(tǒng)設(shè)計(jì)主要內(nèi)容:確定生活給水設(shè)計(jì)標(biāo)準(zhǔn)與參數(shù)進(jìn)行用水量計(jì)算;選擇給水方式,布置給水管道及設(shè)備;進(jìn)行給水管網(wǎng)水力計(jì)算及室內(nèi)所需水壓的計(jì)算;高位水箱、貯水池容積計(jì)算并確定構(gòu)造尺寸;選擇生活水泵;確定管材及設(shè)備;繪制給水系統(tǒng)的平面圖、系統(tǒng)圖及衛(wèi)生間大樣圖。5.2 建筑排水系統(tǒng)設(shè)計(jì)主要內(nèi)容:選擇排水體制;確定排水系統(tǒng)的形式和污水處理方法;排水管道水力計(jì)算及通氣系統(tǒng)計(jì)算;選擇管材及管道安裝;繪制排水系統(tǒng)的平面圖及系統(tǒng)圖。5.3 建筑消防系統(tǒng)設(shè)計(jì)(消火栓系統(tǒng))主要內(nèi)容:消防水量計(jì)算;消防給水方式的確定;消防栓、消防管道布置;消防管道水力計(jì)算及消防水壓計(jì)算;消防泵的選擇;確定穩(wěn)壓系統(tǒng);繪制消火栓系統(tǒng)的平面圖及系統(tǒng)圖。6成果形式最終設(shè)計(jì)成果有:設(shè)計(jì)圖紙,要求使用計(jì)算機(jī)繪圖;計(jì)算說明書和設(shè)計(jì)說明,包含有管道直徑的選用計(jì)算過程、水力計(jì)算過程和設(shè)備的選用計(jì)算過程等詳細(xì)內(nèi)容。7進(jìn)度計(jì)劃此次設(shè)計(jì)工作的起止日期為:2005年4月4日2005年6月22日?,F(xiàn)制定以下簡要進(jìn)度計(jì)劃:4.44.22 文獻(xiàn)初步調(diào)研,完成開題報(bào)告。在此過程中查閱各類相關(guān)文獻(xiàn),明確設(shè)計(jì)程序及具體采用的方法,結(jié)合畢業(yè)實(shí)習(xí)所學(xué)知識,為設(shè)計(jì)工作打下良好基礎(chǔ)。4.245.27 根據(jù)建筑圖紙和所掌握的資料,進(jìn)行系統(tǒng)設(shè)計(jì),并繪圖。5.306.20 完成計(jì)算說明書與設(shè)計(jì)說明,設(shè)計(jì)圖定稿,并對設(shè)計(jì)成果進(jìn)行檢查,避免不必要的錯(cuò)、漏現(xiàn)象發(fā)生。6.206.24 畢業(yè)設(shè)計(jì)答辯。8論文提綱 前言 目錄一、 設(shè)計(jì)任務(wù)及設(shè)計(jì)資料(一) 設(shè)計(jì)任務(wù)書(二) 設(shè)計(jì)文件及設(shè)計(jì)資料二、 設(shè)計(jì)計(jì)算(一) 建筑給水系統(tǒng)的計(jì)算(二) 建筑排水系統(tǒng)的計(jì)算(三) 建筑消防系統(tǒng)的計(jì)算三、 設(shè)計(jì)說明(一) 建筑給水工程(二) 建筑排水工程(三) 建筑消防工程(四) 主要構(gòu)筑物與設(shè)備 總結(jié) 主要參考文獻(xiàn)9參考文獻(xiàn) (1)姜文源主編,建筑給水排水常用設(shè)計(jì)規(guī)范詳解手冊,北京,中國建筑工業(yè)出版社,1996年; (2)趙基興編著,建筑給排水實(shí)用新技術(shù),上海,同濟(jì)大學(xué)出版社,2000年; (3)馬金 等編著,建筑給水排水工程,北京,清華大學(xué)出版社,2004年; (4)陳秀生主編,給水排水設(shè)計(jì)手冊建筑給水排水,第二版,北京,中國建筑工業(yè)出版社,2001年。上海某辦公樓給排水系統(tǒng)設(shè)計(jì)設(shè)計(jì)總說明一、設(shè)計(jì)任務(wù)來源此次設(shè)計(jì)的對象是上海某辦公樓給排水工程(含消防),經(jīng)復(fù)興東路隧道工程隧道管理中心委托,由上海市隧道工程軌道交通設(shè)計(jì)研究院委派進(jìn)行設(shè)計(jì)。二、設(shè)計(jì)標(biāo)準(zhǔn) 本設(shè)計(jì)中,給排水系統(tǒng)設(shè)計(jì)嚴(yán)格按照設(shè)計(jì)規(guī)范:建筑給水排水設(shè)計(jì)規(guī)范(GB50015-2003)實(shí)施;消防系統(tǒng)設(shè)計(jì)則按照設(shè)計(jì)規(guī)范:上海民用建筑水滅火系統(tǒng)設(shè)計(jì)規(guī)程(DGJ08-94-2001)實(shí)施。三、設(shè)計(jì)原則(一)設(shè)計(jì)依據(jù)及設(shè)計(jì)范圍根據(jù)業(yè)主所提設(shè)計(jì)委托書及有關(guān)部門批文,按照現(xiàn)行設(shè)計(jì)規(guī)范和有關(guān)規(guī)定,負(fù)責(zé)本工程的室內(nèi)給排水系統(tǒng)及消防系統(tǒng)的設(shè)計(jì)。(二)給水排水系統(tǒng)由于市政給水管網(wǎng)所提供的壓力常年不足,本設(shè)計(jì)生活給水系統(tǒng)為水池水泵供水系統(tǒng),水池水泵集中設(shè)于地下室。15T屋頂水箱僅用于消防,貯存室內(nèi)10min的消防用水量,由生活水泵供水。生活水泵采用自動啟動。本工程室內(nèi)原則上采用污廢水分流排放。(三)消防系統(tǒng)室內(nèi)消火栓系統(tǒng)采用臨時(shí)高壓系統(tǒng),消防用水量為20L/s,由設(shè)在消防泵房內(nèi)的消火栓泵兩臺(互備),直接抽吸市政消防給水管,設(shè)水泵結(jié)合器二套。(四)設(shè)備及管材配件 1. 主要設(shè)備及配件見主要設(shè)備及材料表。 2. 管材及閥門 a. 給水管采用PP-R管,熱熔連接;污、廢水管采用硬聚氯乙烯排水管; b. 水箱、水池的進(jìn)水管、出水管、排污管,自水箱、水池至閥門間的管段也采用PP-R管。水池內(nèi)壁貼瓷磚; c. 消防管道均采用鑄鐵管,法蘭連接; d. 水管上的閥門DN50,采用J11T-10型截止閥,DN50采用Z45T-10型閘閥。(五)管道及設(shè)備安裝 1. 管道水平支吊架應(yīng)根據(jù)需要現(xiàn)場設(shè)置,具體做法參見國標(biāo)S161。所有管道應(yīng)盡量貼樓板,梁,柱安裝。 2. 國產(chǎn)衛(wèi)生設(shè)備安裝見國標(biāo)99S304。 3. 室內(nèi)排水管道的坡度:De50i = 0.035De75i = 0.025De110i = 0.020 4. 排水管道的橫管與橫管、橫管與立管的連接,應(yīng)采用45三通或四通和90斜三通或斜四通。立管底部與排出管連接處,應(yīng)采用兩個(gè)45彎頭或采用半徑不小于4倍管徑的90彎頭。 5. 所有衛(wèi)生潔具自帶或配套存水彎。 6. 管道穿越樓板、屋面處,其空隙部分采用C10細(xì)石混凝土二次搗實(shí),底部應(yīng)采用M10水泥砂漿,砌筑寬度不小于30mm,阻水圈高度不小于25mm,或設(shè)置高出地平面不小于50mm的硬聚氯乙烯護(hù)套管,套管根部應(yīng)窩嵌在地面找平層內(nèi)。 7. 給排水管道穿梁、樓板等處需預(yù)留孔洞,施工單位務(wù)必在澆鑄混凝土前與土建密切合作,復(fù)核預(yù)留孔洞的定位及尺寸大小。 8. 室內(nèi)消火栓箱除無墻處明裝外其余嵌墻安裝,每個(gè)消火栓箱安裝參見2001滬S313。 9. 水泵接合器型號為SQ型地上式消防水泵接合器(帶安全閥)。(六)管道設(shè)備油漆及保溫 1. 油漆室內(nèi)明露的金屬設(shè)備支吊架,均需除銹后刷紅丹兩道,防銹漆兩道。 2. 保溫室內(nèi)明露的給水管道均采用超細(xì)玻璃棉保溫,保溫層厚度為30mm。外包玻璃布防水,具體做法詳見國標(biāo)87S159。(七)管道試壓 1. 室內(nèi)生活給水管道安裝完后,應(yīng)以1.5倍的工作壓力試壓,消防試壓為1.6Mpa,試壓要求按DBJ/CT501-99規(guī)程執(zhí)行。 2. 室內(nèi)暗裝或埋地的排水管道,在隱蔽前必須做灌水試驗(yàn),其灌水高度應(yīng)不低于底層高度。灌水15分鐘水面下降后,再灌滿延續(xù)5分鐘,液面不下降為合格。 3. 排水立管需作通水通球試驗(yàn)。本說明未述及部分,按國家有關(guān)規(guī)定和圖紙上的補(bǔ)充說明處理。本設(shè)計(jì)圖紙除標(biāo)高以米計(jì)外,其余均以毫米計(jì),室內(nèi)外地坪標(biāo)高為相對標(biāo)高,并以底層室內(nèi)地坪標(biāo)高作為基準(zhǔn)標(biāo)高。給水管是指管中心標(biāo)高,排水管是指管內(nèi)底標(biāo)高。四、主要技術(shù)資料(一)建筑設(shè)計(jì)資料1. 建筑物各層平面圖,立面圖,衛(wèi)生間大樣圖。2. 該辦公樓為五層高鋼筋混凝土框架結(jié)構(gòu)的建筑物,地下室層高4.9米,一至五層層高依次為4.5米、3.8米、5.5米、4.9米及3.8米;首層室內(nèi)地面標(biāo)高為0.000米。(二)建筑物使用情況1. 建筑物概述:本設(shè)計(jì)的建筑物為五層辦公樓。2. 給水水源:建筑物東面有城市給水干管作為本建筑物水源,北面有市政消防給水管網(wǎng),管徑為DN150,管頂覆土厚度為1米,常年可提供的工作壓力為100kPa。 3. 排水條件:建筑物北面有城市排水管道,管徑為DN400,管頂覆土厚度為1.8米。Water Supply And Drainage Engineering Design for A Certain Office Building of ShanghaiGeneral Illustrate of the DesignI. Source of the designThe target of the design is water supply and drainage engineering of a certain office building of Shanghai. The task is entrusted by the “Tunnel Project Tunnel Administration Center of East Fu Xing Road”, appointed to design by the “Tunnel Project Track Traffic Design Research Institute of Shanghai”.II. Design standardThe water supply and drainage engineering design is processed according to the design specification, “Code for Design of Building Water Supply and Drainage” (GB50015-2003) strictly, while the fire-fighting system design is according to the “Code for Design of Water Extinguishing System Of Civil Buildings” (DGJ08-94-2001).III. Design principle 1. Design considerations and range of the designingAccording to the design trust deed and written instructions or comments of the related departments given by the owner, the design of the water supply and drainage system and fire-fighting system in the room is carried out according to current design specification and relevant regulations. 2. Water supply and drainage systemBecause the pressure of the municipal water supply pipe network is insufficient throughout the year, the life water supply system is the pond - the water supply system of the water pump originally. The pond and the water pump concentrate on locating the basement. 15T roof water tank is used in fire control only, storing indoor fire control water consumption of 10min. The water is supplied by the life water pump. The life water pump is started automatically.In this project, it is adopted dirty to abolish moisture discharged to shed in principle. 3. Fire-fighting systemThe indoor fire hydrant system adopts the temporary high-pressure system. The water consumption of fire control is 20L/s. Two fire pumps which are set up in the pump house for fire control (standby for each other) suck the feed pipe of municipal fire control directly. Two sets combining device of water pumps are set up. 4. Equipment and pipe fittings (1) Capital equipment and fittings meet the capital equipment and material form. (2) Pipe material and valvea. Feed pipes adopt PP-R pipes, hot to melt and join; the drainage pipes adopt UPVC pipes;b. Penstock, outlet pipes, blowdown pipes of the water tank and pond, and the pipes since water tank and pond to valves also adopt PP-R pipes all. The pond inboard wall sticks to the ceramic tile;c. The fire control pipeline adopts cast iron pipe, the flange is joined;d. Valves on the water pipe, DN50, adopt the stop valve of the Model J11T-10, while DN50, adopt the floodgate valve of the Model Z45T-10. 5. The pipeline and rig up(1) Pipeline level prop hanger should set up live according to need, concrete method pay respects to national standard S161. All pipelines should try best to be installed stick to the floor , roof beam, the post.(2) See national standard 99S304 in domestic hygiene rig up.(3) The slope of the indoor drainage pipeline:De50i = 0.035De75i = 0.025De110i = 0.020(4) Drainage pipeline should adopt 45 three direct links or four direct links and 90oblique three direct links or oblique four direct links.(5) All cleaners and polishes are taken by oneself or related trap .(6) The pipeline passes through the floor, roofing place , its space part adopts the detailed stone concrete of C10 two times to smash really, the bottom should adopt the cement mortar of M10. The width of bricks laying are not smaller than 30mm, and the height of water blocking ring is not smaller than 25mm. Sleeve pipe root inlay in ground making level layer in conformity with nest.(7) Give drainage pipeline wear roof beam , floor ,etc., it should reserve holes in a utensil, unit in charge of construction must cooperate with the building construction closely in front of the concrete in casting, check the localization and size of reserving holes.(8) Indoor fire hydrant case have wall office to put the others inlay wall install , each fire hydrant case is to see 2001 Shanghai S313 to install.(9) The adapter type of the water pump, for the SQ type on the ground fire control water pump adapter (taking the relief valve). 6. Pipeline equipment painting and warm keeping(1) PaintingRoom metal equipments that reveal prop up hanger , are needed to be brushed two layers of red lead after eliminating, and two layers of antirust paint.(2) Warm keepingThe water supply pipeline that will be exposed installation in the room adopts the ultra thin glass wool to keep warm , the thickness of heat preservation is 30mm. Outside make glass cloth to be waterproof, the concrete method can be looked up from national standard 87S159. 7. Pressure in pipelines test(1) After the supply water pipeline is installed in the room, it should be tested by 1.5 times of working pressure. The fire-fighting pipeline pressure test is processed by 1.6MPa.(2) The drainage pipeline of the ground is put or buried secretly in the room , must be poured water to test before being concealed. It should highly not be lower than the height of ground floor to pour water. Pouring water for 15 minutes after the surface of water drops, fill with and last 5 minutes , it is qualified not to drop to the liquid .(3) Drain off water and set up and is in charge of needing to make open ball of open water to test.Originally prove that has not been stated, deal with the additional remarks on the drawing according to the pertinent regulations of state.This design drawing is except that elevation is counted with the rice, the others are counted with mm. , level ground elevation is the relative elevation inside and outside the room, regard inland level ground elevation of room of ground floor as basic elevation . The feed pipe refers to in charge of the centre elevationing , the drain pipe refers to the bottom elevation while managing.IV. Architectural design materials 1. Construction design material(1) The plane figure of every storey of the building, elevation, the big master drawing of the bathroom.(2) This office building is a building of structure of a five-storey reinforced concrete frame. Storey of the basement is 4.9m high, and the 1st floor to the 5th floor is successively 4.5m, 3.8m, 5.5m, 4.9m, 3.8m high. The elevation of the first layer of indoor ground is 0.000m. 2. Operating position of the building The building originally designed is the five - storey office building .There are the municipal water supply pipe network in the east of the building, municipal fire control water supply pipe network in the north. The pipe diameter is DN150, it is 1 meter to in charge of carrying and covering the thickness of soil, long-term working pressure that can be offered is 100kPa.目錄1 緒論 1 1.1 本課題研究背景 1 1.2 課題的意義與目的 1 1.1.1 意義 1 1.1.2 目的和作用 1 1.3 技術(shù)要求及指導(dǎo)思想 1 1.4 本課題在國內(nèi)外的發(fā)展?fàn)顩r 2 1.4.1 我國近年建筑給排水技術(shù)情況回顧 2 1.4.2 西方發(fā)達(dá)國家目前建筑給排水的一些特點(diǎn) 3 1.5 本課題應(yīng)解決的主要問題 42 設(shè)計(jì)說明書 5 2.1 室內(nèi)給水工程 5 2.1.1 給水系統(tǒng)選擇 5 2.1.2 系統(tǒng)組成 5 2.1.3 加壓設(shè)備及構(gòu)筑物 5 2.2 室內(nèi)排水工程 5 2.2.1 排水系統(tǒng)選擇 5 2.2.2 系統(tǒng)組成 5 2.3 室內(nèi)消防工程 5 2.3.1 消防系統(tǒng)選擇 5 2.3.2 系統(tǒng)組成 6 2.3.3 主要設(shè)備 6 2.4 管道布置及設(shè)備安裝要求 6 2.4.1 給水管道布置與設(shè)備安裝要求 6 2.4.2 排水管道布置與設(shè)備安裝要求 7 2.4.3 消防管道布置與設(shè)備安裝要求 83 計(jì)算說明書 11 3.1 室內(nèi)給水系統(tǒng)的計(jì)算 11 3.1.1 給水用水定額及時(shí)變化系數(shù) 11 3.1.2 最高日用水量 11 3.1.3 最高日最大時(shí)用水量 11 3.1.4 設(shè)計(jì)秒流量的計(jì)算 11 3.1.5 室內(nèi)所需水壓的計(jì)算 11 3.1.6 水箱、貯水池的容積計(jì)算 12 3.1.7 水泵的選型計(jì)算 12 3.2 室內(nèi)排水系統(tǒng)的計(jì)算 14 3.2.1 設(shè)計(jì)要點(diǎn) 14 3.2.2 設(shè)計(jì)計(jì)算 14 3.3 消火栓系統(tǒng)的計(jì)算 20 3.3.1 消火栓的保護(hù)半徑 20 3.3.2 消火栓口所需壓力 20 3.3.3 消防用水量計(jì)算 20致謝 23參考文獻(xiàn) 24Laminar and Turbulent Flow Observation shows that two entirely different types of fluid flow exist. This was demon- strated by Osborne Reynolds in 1883 through an experiment in which water was discharged from a tank through a glass tube. The rate of flow could be controlled by a valve at the outlet, and a fine filament of dye injected at the entrance to the tube. At low velocities, it was found that the dye filament remained intact throughout the length of the tube, showing that the particles of water moved in parallel lines. This type of flow is known as laminar, viscous or streamline, the particles of fluid moving in an orderly manner and retaining the same relative positions in successive cross- sections.As the velocity in the tube was increased by opening the outlet valve, a point was eventually reached at which the dye filament at first began to oscillate and then broke up so that the colour was diffused over the whole cross-section, showing that the particles of fluid no longer moved in an orderly manner but occupied different relative position in successive cross-sections. This type of flow is known as turbulent and is characterized by continuous small fluctuations in the magnitude and direction of the velocity of the fluid particles, which are accompanied by corresponding small fluctuations of pressure.When the motion of a fluid particle in a stream is disturbed, its inertia will tend to carry it on in the new direction, but the viscous forces due to the surrounding fluid will tend to make it conform to the motion of the rest of the stream. In viscous flow, the viscous shear stresses are sufficient to eliminate the effects of any deviation, but in turbulent flow they are inadequate. The criterion which determines whether flow will be viscous of turbulent is therefore the ratio of the inertial force to the viscous force acting on the particle.The ratioThus, the criterion which determines whether flow is viscous or turbulent is the quantity vl/, known as the Reynolds number. It is a ratio of forces and, therefore, a pure number and may also be written as ul/v where is the kinematic viscosity (v=/).Experiments carried out with a number of different fluids in straight pipes of different diameters have established that if the Reynolds number is calculated by making 1 equal to the pipe diameter and using the mean velocity v, then, below a critical value of vd/ = 2000, flow will normally be laminar (viscous), any tendency to turbulence being damped out by viscous friction. This value of the Reynolds number applies only to flow in pipes, but critical values of the Reynolds number can be established for other types of flow, choosing a suitable characteristic length such as the chord of an aerofoil in place of the pipe diameter. For a given fluid flowing in a pipe of a given diameter, there will be a critical velocity of flow corresponding to the critical value of the Reynolds number, below which flow will be viscous.In pipes, at values of the Reynolds number 2000, flow will not necessarily be turbulent. Laminar flow has been maintained up to Re = 50,000, but conditions are unstable and any disturbance will cause reversion to normal turbulent flow. In straight pipes of constant diameter, flow can be assumed to be turbulent if the Reynolds number exceeds 4000.Pipe Networks An extension of compound pipes in parallel is a case frequently encountered in municipal distribution system, in which the pipes are interconnected so that the flow to a given outlet may come by several different paths. Indeed, it is frequently impossible to tell by inspection which way the flow travels. Nevertheless, the flow in any networks, however complicated, must satisfy the basic relations of continuity and energy as follows:1. The flow into any junction must equal the flow out of it.2. The flow in each pipe must satisfy the pipe-friction laws for flow in a single pipe.3. The algebraic sum of the head losses around any closed circuit must be zero.Pipe networks are generally too complicated to solve analytically, as was possible in the simpler cases of parallel pipes. A practical procedure is the method of successive approximations, introduced by Cross. It consists of the following elements, in order:1. By careful inspection assume the most reasonable distribution of flows that satisfies condition 1.2. Write condition 2 for each pipe in the form hL = KQn (7.5)where K is a constant for each pipe. For example, the standard pipe-friction equation would yield K = 1/C2 and n = 2 for constant f. Minor losses within any circuit may be included, but minor losses at the junction points are neglected.3. To investigate condition 3, compute the algebraic sum of the head losses around each elementary circuit. hL = KQn. Consider losses from clockwise flows as positive, counterclockwise negative. Only by good luck will these add to zero on the first trial.4. Adjust the flow in each circuit by a correction, Q, to balance the head in that circuit and give KQn = 0. The heart of this method lies in the determination of Q. For any pipe we may writeQ = Q0 Qwhere Q is the correct discharge and Q0 is the assumed discharge. Then, for a circuit (7.6)It must be emphasized again that the numerator of Eq. (7.6) is to be summed algebraically, with due account of sign, while the denominator is summed arithmetically. The negative sign in Eq. (7.6) indicates that when there is an excess of head loss around a loop in the clockwise direction, the Q must be subtracted from clockwise Q0s and added to counterclockwise ones. The reverse is true if there is a deficiency of head loss around a loop in the clockwise direction.5. After each circuit is given a first correction, the losses will still not balance because of the interaction of one circuit upon another (pipes which are common to two circuits receive two independent corrections, one for each circuit). The procedure is repeated, arriving at a second correction, and so on, until the corrections become negligible.Either form of Eq. (7.6) may be used to find Q. As values of K appear in both numerator and denominator of the first form, values proportional to the actual K may be used to find the distribution. The second form will be found most convenient for use with pipe-friction diagrams for water pipes.An attractive feature of the approximation method is that errors in computation have the same effect as errors in judgment and will eventually be corrected by the process.The pipe-networks problem lends itself well to solution by use of a digital computer. Programming takes time and care, but once set up, there is great flexibility and many man-hours of labor can be saved.The Future of Plastic Pipe at Higher PressuresParticipants in an AGA meeting panel on plastic pipe discussed the possibility of using polyethylene gas pipe at higher pressures. Topics included the design equation, including work being done by ISO on an updated version, and the evaluation of rapid crack propagation in a PE pipe resin. This is of critical importance because as pipe is used at higher pressure and in larger diameters, the possibility of RCP increases.Several years ago, AGAs Plastic Pipe Design Equation Task Group reviewed the design equation to determine if higher operating pressures could be used in plastic piping systems. Members felt the performance of our pipe resins was not truly reflected by the design equation. It was generally accepted that the long-term properties of modern resins far surpassed those of older resins. Major considerations were new equations being developed and selection of an appropriate design factor.Improved pipe performanceMany utilities monitored the performance of plastic pipe resins. Here are some of the long-term tests used and the kinds of performance change they have shown for typical gas pipe resins.Elevated temperature burst testThey used tests like the Elevated Temperature Burst Test, in which the long-term performance of the pipe is checked by measuring the time required for formation of brittle cracks in the pipe wall under high temperatures and pressures (often 80 degrees C and around 4 to 5-MPa hoop stress). At Consumers Gas we expected early resins to last at least 170 hrs. at 80 degrees C and a hoop stress of 3 MPa. Extrapolation showed that resins passing these limits should have a life expectancy of more than 50 yrs. Quality control testing on shipments of pipe made from these resins sometimes resulted in product rejection for failure to meet this criterion.At the same temperature, todays resins last thousands of hours at hoop stresses of 4.6 MPa. Tests performed on pipe made from new resins have been terminated with no failure at times exceeding 5,700 hrs. These results were performed on samples that were squeezed off before testing. Such stresses were never applied in early testing. When extrapolated to operating conditions, this difference in test performance is equivalent to an increase in lifetime of hundreds (and in some cases even thousands) of years.Environmental stress crack resistance testSome companies also used the Environmental Stress Crack Resistance test which measured brittle crack formation in pipes but which used stress cracking agents to shorten test times.This test has also shown dramatic improvement in resistance brittle failure. For example, at my company a test time of more than 20 hrs. at 50 degrees C was required on our early resins. Todays resins last well above 1,000 hrs. with no failure.Notch testsNotch tests, which are quickly run, measure brittle crack formation in notched pipe or molded coupon samples. This is important for the newer resins since some other tests to failure can take very long times. Notch test results show that while early resins lasted for test times ranging between 1,000 to 10,000 min., current resins usually last for longer than 200,000 min.All of our tests demonstrated the same thing. Newer resins are much more resistant to the growth of brittle crack than their predecessors. Since brittle failure is considered to be the ultimate failure mechanism in polyethylene pipes, we know that new materials will last much longer than the old. This is especially reassuring to the gas industry since many of these older resins have performed very well in the field for the past 25 yrs. with minimal detectable change in properties.While the tests showed greatly improved performance, the equation used to establish the pressure rating of the pipe is still identical to the original except for a change in 1978 to a single design factor for all class locations.To many it seemed that the methods used to pressure rate our pipe were now unduly conservative and that a new design equation was needed. At this time we became aware of a new equation being balloted at ISO. The methodology being used seemed to be a more technically correct method of analyzing the data and offered a number of advantages.Thermal Expansion of Piping and Its CompensationA very relevant consideration requiring careful attention is the fact that with temperature of a length of pipe raised or lowered, there is a corresponding increase or decrease in its length and cross-sectional area because of the inherent coefficient of thermal expansion for the particular pipe material. The coefficient of expansion for carbon steel is 0.012 mm/mC and for copper 0.0168mm/mC. Respective module of elasticity are for steel E = 2071.06kN/m2 and for copper E = 103106 kN/m2. As an example, assuming a base temperature for water conducting piping at 0C, a steel pipe of any diameter if heated to 120C would experience a linear extension of 1.4 mm and a similarly if heated to copper pipe would extend by 2.016 mm for each meter of their respective lengths. The unit axial force in the steel pipe however would be 39% greater than for copper. The change in pipe diameter is of no practical consequence to linear extension but the axial forces created by expansion or contraction are con- siderable and capable of fracturing any fitments which may tend to impose a restraint ; the magnitude of such forces is related to pipe size. As an example, in straight pipes of same length but different diameters, rigidly held at both ends and with temperature raised by say 100C, total magnitude of linear forces against fixed points would be near enough proportionate to the respective diameters.It is therefore essential that design of any piping layout makes adequate com- pensatory provision for such thermal influence by relieving the system of linear stresses which would be directly related to length of pipework between fixed points and the range of operational temperatures.Compensation for forces due to thermal expansion. The ideal pipework as far as expansion is concerned, is one where maximum free movement with the minimum of restraint is possible. Hence the simplest and most economical way to ensure com- pensation and relief of forces is to take advantage of changes in direction, or where this is not part of the layout and long straight runs are involved it may be feasible to introduce deliberate dog-leg offset changes in direction at suitable intervals.As an alternative, at calculated intervals in a straight pipe run specially designed expansion loops or “U” bends should be inserted. Depending upon design and space availability, expansion bends within a straight pipe run can feature the so called double offset “U” band or the horseshoe type or “l(fā)yre” loop. The last named are seldom used for large heating networks; they can be supplied in manufacturers standard units but require elaborate constructional works for underground installation. Anchored thermal movement in underground piping would normally be absorbed by three basic types of expansion bends and these include the “U” bend, the “L” bend and the “Z” bend. In cases of 90 changes indirection the “L” and “Z” bends are used. Principles involved in the design of provision for expansion between anchor points are virtually the same for all three types of compensator. The offset “U” bend is usually made up from four 90 elbows and straight pipes; it permits good thermal displacement and imposes smaller anchor loads than the other type of loop. This shape of expansion bend is the standardised pattern for prefabricated pipe-in-pipe systems.All thermal compensators are installed to accommodate an equal amount of expansion or contraction; therefore to obtain full advantage of the length of thermal movement it is necessary to extend the unit during installation thus opening up the loop by an extent roughly equal the half the overall calculated thermal movement. This is done by “cold-pull” or other mechanical means. The total amount of extension between two fixed points has to be calculated on basis of ambient temperature prevailing and operational design temperatures so that distribution of stresses and reactions at lower and higher temperatures are controlled within permissible limits. Pre-stressing does not affect the fatigue life of piping therefore it does not feature in calculation of pipework stresses .There are numerous specialist publication dealing with design and stressing calculations for piping and especially for proprietary piping and expansion units; comprehensive experience back design data as well as charts and graphs may be obtained in manufacturers publications, offering solutions for every kind of pipe stressing problem.As an alternative to above mentioned methods of compensation for thermal expansion and useable in places where space is restricted, is the more expensive bellows or telescopic type mechanical compensator. There are many proprietary types and models on the market and the following types of compensators are generally used.The bellows type expansion unit in form of an axial compensator provides for expansion movement in a pipe along its axis; motion in this bellows is due to tension or compression only. There are also articulated bellows units restrained which combine angular and lateral movement; they consist of double compensator units restrained by straps pinned over the center of each bellowsor double tied thus being restrained over its length. Such compensators are suitable for accommodating very pipeline expansion and also for combinations of angular and lateral movements.層流與紊流有兩種完全不同的流體流動形式存在,這一點(diǎn)在1883年就由Osborne Reynolds 用試驗(yàn)演示證明。在試驗(yàn)里,水通過玻璃管從水箱里放出。流量由出口處的閥門來控制,一股很細(xì)的染色流束由入口注入玻璃管內(nèi)。在較低的流速時(shí),可以看到染色流束在玻璃管中保持著一條完整的遷流。這表明流體粒子以平行的層狀流動。這種粘性流體的流動就是我們所知的層流,流體各層的質(zhì)點(diǎn)以有序的方式移動,并在連續(xù)的截面上保持著相同的相對位置。打開出口閥門,管子里的速度就提高。隨著速度提高,最后會達(dá)到這樣的程度,即染色流束起初開始擺動然后破碎,這樣顏色就擴(kuò)散在整個(gè)截面上,這表明流體粒子已不再有次序流動卻在連續(xù)的截面上占有相對不同的位置。這種流體的流動形式就是紊流,它的特點(diǎn)就是不斷產(chǎn)生無數(shù)大小不等的渦團(tuán),質(zhì)點(diǎn)摻混使得空間各點(diǎn)的速度隨時(shí)間無規(guī)則地變化。與之相關(guān)聯(lián),壓強(qiáng)也隨之無規(guī)則地變化。當(dāng)一條流束中的某個(gè)流體粒子的運(yùn)動被擾亂,則它的慣性會使它移向新的方向,但周圍流體的粘滯力會使它與其余流束的運(yùn)動保持一致。在粘性流體中,粘性切應(yīng)力足以抵消任何偏差的影響,但在紊流中是不夠的。因此,確定流動是粘滯性的還是紊流性的標(biāo)準(zhǔn)就是作用在粒子上的慣性力和粘性力之比:這樣,用來判斷流動是粘滯性的還是紊流性的標(biāo)準(zhǔn)就是vl/,也就是雷諾數(shù)。這是力之間的比,因此理論上也可以寫成ul/v(v=/,流體的運(yùn)動粘滯系數(shù))。在不同管徑的直管里用許多不同流體所進(jìn)行的試驗(yàn)已經(jīng)證實(shí),如雷諾數(shù)是通過使L等于管徑并且使用平均速度v來計(jì)算,那么在低于臨界值vd/ = 2000的條件下流動一般是層流(粘滯流動),任何紊流的傾向都會由于粘滯摩擦而受到抑制。這個(gè)雷諾數(shù)的值僅適用于管道中的流體,但雷諾數(shù)的臨界值可以用來確定其他形式的流動,例如選擇合適的弦桿翼剖面來代替管道直徑。對于已知直徑的管道中的流體而言,會有一個(gè)臨界流速vc,以及對應(yīng)的雷諾數(shù),如果低于這個(gè)數(shù),則表明流體是粘滯流動。在管道中,雷諾數(shù)值大于2000的情況下,流體不一定就變?yōu)槲闪鳌恿骺梢跃S持到Re = 50,000,但是條件并不穩(wěn)定,任何干擾都會使其它又變?yōu)橐话愕奈闪鳌T谥睆揭欢ǖ闹惫苤?,如果雷諾數(shù)超過4000那么流體就有可能變?yōu)槲闪鳌9芫W(wǎng)平行復(fù)合管道的延伸是市政分配系統(tǒng)中常見的一種情況,在這種情況下管道相互連接,使得通向某一出口的流體可以來自不同的路徑。的確,通過觀察往往很難說清楚流體將流經(jīng)哪一個(gè)管路。但是,不管管網(wǎng)有多復(fù)雜,其中的流體都必須確保連續(xù)性與能量的基礎(chǔ)關(guān)系。如下所述:1 流入接合處的流體必須與流出的等量;2 在每根管中的流體都必須滿足流體在單管中的管道摩擦定律;3 在任何閉合回路中,水頭損失的代數(shù)和必須為0。管網(wǎng)一般來講由于太過復(fù)雜而難以分析解決,但在簡單一些的情況下是可以的,例如平行管。Cross 介紹了一種實(shí)用的程序,采用的是連續(xù)性近似法。它由以下的原理組成,包括:1 通過仔細(xì)的觀察采取最合理的流體分配方案以滿足條件1;2 對每根管道以方程hL = KQn來判斷是否滿足條件2,式中K是每根管的特性常數(shù)。例如,標(biāo)準(zhǔn)管道摩擦方程中的K = 1/C2以及n = 2。任何環(huán)路中較小的沿程水頭損失可能是包括的,但局部水頭損失可以忽略不計(jì)。3 為了研究條件3,計(jì)算每個(gè)基本環(huán)路中水頭損失的代數(shù)和。hL = KQn。假設(shè)順時(shí)針方向流動的損失為正,逆時(shí)針的則為負(fù),那么在第一次試驗(yàn)中,它們的和只有在非常幸運(yùn)的情況下才會為零。4 通過一個(gè)修正值Q來調(diào)整每條環(huán)路中的流體,使該管路中的水頭平衡,并給出KQn = 0。這個(gè)方法的核心取決于Q的確定。對于任何管道我們有:Q = Q0 Q式中Q是準(zhǔn)確的流量而Q0是假定的流量。那么,對于一個(gè)環(huán)路而言: (7.6)必須再次強(qiáng)調(diào)的是方程(7.6)的分子和分母都是采用了適當(dāng)?shù)挠?jì)算符號確定的。方程(7.6)中的負(fù)號表明,當(dāng)順時(shí)針方向的環(huán)路上有過量的水頭損失時(shí),Q必須從順時(shí)針方向的Q0中減去,并增加到逆時(shí)針方向上去。如果順時(shí)針方向的環(huán)路上水頭損失不足時(shí),情況正好相反。5在每條環(huán)路都給予了一個(gè)最初的修正值后,由于環(huán)路之間的相互影響,損失仍不平衡(一些兩條環(huán)路共有的管道就有兩個(gè)單獨(dú)的修正值,每個(gè)值對應(yīng)一條環(huán)路)。重復(fù)這樣的程序,獲得第二個(gè)修正值,乃至第三、第四個(gè)等等,直到修正值可以忽略不計(jì)。方程(7.6)的兩種形式都可以用來找出Q。由于K值同時(shí)出現(xiàn)在第一種形式的分子和分母上,相應(yīng)實(shí)際的K值就可以用來確定分配量。結(jié)合水管的管道摩擦力圖表,第二種方程形式使用起來最簡便。近似法最吸引人的一個(gè)特點(diǎn)就是計(jì)算上的誤差與判斷誤差有相同的效果,而最終它們會在過程中被加以改正。管網(wǎng)問題非常適合于采用計(jì)算機(jī)來解決。編制程序需花費(fèi)大量的時(shí)間和精力,但是一旦完成,就有很大的機(jī)動靈活性,許多耗人費(fèi)時(shí)的勞動就可省去。更高壓力下塑料管道的前景美國煤氣協(xié)會AGA的一個(gè)針對塑料管道的專案小組的成員討論了在較高壓力下使用聚乙烯輸氣管的的可能性。討論的主題包括有設(shè)計(jì)方程(其中包括國際科學(xué)組織ISO在更新版本上完成的工作),以及對PE管樹脂上裂縫快速擴(kuò)展的評估。這一點(diǎn)非常重要,因?yàn)楫?dāng)管道在較高壓力下使用、而管徑更大的情況下,鋼筋混凝土管的可能性增加了。若干年以前,AGA的塑料管道設(shè)計(jì)任務(wù)小組檢查了設(shè)計(jì)方程,以確定是否能在塑料管道系統(tǒng)中使用更高的工作壓力。小組成員認(rèn)為管道樹脂的性能并沒有通過設(shè)計(jì)方程反映出來。一般認(rèn)為新的樹脂塑管在耐用性上遠(yuǎn)遠(yuǎn)勝過過去的樹脂塑管,因此主要考慮的問題是新方程的發(fā)展以及合適的設(shè)計(jì)要素的選擇。改良的管道性能許多設(shè)備用來監(jiān)測塑料管道樹脂的性能。在這里講述一下一些針對典型的輸氣管道樹脂進(jìn)行過的耐久性測試,以及幾種性能上的變化。溫升爆裂測試他們使用像溫升爆裂測試之類的測試。在這一測試中管系的耐久性能通過高溫和高壓下管壁形成脆裂所需的時(shí)間來校核(通常是80攝氏度和4-5MPa的環(huán)壓下)。在供應(yīng)燃?xì)鈺r(shí)我們希望老的樹脂塑管在80攝氏度、3MPa的環(huán)壓下至少可以堅(jiān)持使用170個(gè)小時(shí)。推斷表明通過了這些極限的樹脂預(yù)期其壽命應(yīng)該能超過50年。裝運(yùn)時(shí)對這些樹脂塑管質(zhì)量檢測,有時(shí)會由于沒有達(dá)到這一標(biāo)準(zhǔn)而對該產(chǎn)品拒絕使用。在相同溫度條件下,今天的樹脂塑管在4.6MPa環(huán)壓下可持續(xù)使用數(shù)千小時(shí)。測試表明用新樹脂制造的管道可使用超過5700小時(shí)而沒有任何損壞。這些結(jié)果是在臨測試前檢出的(樹脂)抽樣得出的。這種壓力從未在早期的測試中使用過。根據(jù)工作條件推斷,測試性能上的區(qū)別與數(shù)百年的壽命增長是相等的(某些情況下甚至是數(shù)千年)。環(huán)壓下的防裂測試也有些公司進(jìn)行了環(huán)壓下的防裂測試,用來測量管道中脆裂的形成,并加大了壓力來減短測試的時(shí)間。這個(gè)試驗(yàn)表明了在防止脆裂上的驚人的改進(jìn)。例如,在我的公司里對于我們的早期樹脂塑管進(jìn)行試驗(yàn)需要20小時(shí)以上的時(shí)間和50攝氏度的溫度。而現(xiàn)在的樹脂塑管能夠良好地持續(xù)1000小時(shí)以上而沒有損壞。槽口測試可以快速進(jìn)行的槽口測試,用來測量帶有槽口的管道或?qū)iT澆鑄的試驗(yàn)管中脆裂的形成。這對新的樹脂塑管非常重要,因?yàn)槠渌脑囼?yàn)需要很長的時(shí)間才能使管道發(fā)生損壞。槽口測試的結(jié)果說明早期的樹脂塑管持續(xù)的試驗(yàn)時(shí)間在1000到10000分鐘之間,而現(xiàn)在的樹脂塑管則通??沙掷m(xù)超過200000分鐘。我們所有的試驗(yàn)證實(shí)了相同的結(jié)果。更新的樹脂塑管比起它們的前輩,對脆裂的防止有著更好的效果。由于認(rèn)為脆裂是聚乙烯管道中結(jié)構(gòu)的最終損壞,因此我們知道新的材料比起舊的來能夠持續(xù)使用更久。這對于燃?xì)夤I(yè)特別可靠,因?yàn)樵S多這些舊的樹脂塑管在過去的25年時(shí)間里表現(xiàn)得非常好,而它們的性能只在最小范圍內(nèi)進(jìn)行了些改變。測試表明了管道性能很大的改進(jìn),過去用來建立管道壓力等級的方程式仍然與原有的相同,除了1978年對于一個(gè)針對所有等級的設(shè)計(jì)因素的改變。從許多方面來看,如今將管道按壓
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