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（1）壓差控制閥應與閥外管網壓差相配套
　　閥(fa)外管網(wang)壓(ya)差(cha)不同(tong)，壓(ya)差(cha)控制閥(fa)工作(zuo)特性曲線是不同(tong)的(de)。因此在設計選用和管網(wang)實際運行(xing)時，應保(bao)證閥(fa)門(men)安(an)裝(zhuang)位(wei)置(zhi)點的(de)管，管網(wang)壓(ya)差(cha)在閥(fa)門(men)允許的(de)范圍內(nei)變化(hua)。實際壓(ya)差(cha)過大或過小都將使(shi)彈(dan)簧失效，導致閥(fa)門(men)無法正常(chang)工作(zuo)。

　　（2）壓差控制閥設定壓差的選取
　　壓差(cha)控制閥設定壓差(cha)應與閥內管(guan)路(lu)系(xi)統在設計流(liu)量下的阻力相匹配，以保證閥門(men)在其最(zui)佳工(gong)作區域工(gong)作。二者相差(cha)過大(da)將導致閥內管(guan)路(lu)系(xi)統實際(ji)流(liu)量過大(da)，從而造成閥外(wai)管(guan)路(lu)系(xi)統水力失調或導致閥內管(guan)路(lu)系(xi)統實際(ji)流(liu)量過小(xiao)影響供熱效(xiao)果。

　　（3）壓差控制閥口徑的選取
　　不同(tong)口(kou)徑的(de)壓差控制(zhi)閥(fa)(fa)控制(zhi)的(de)流量(liang)范圍(wei)不同(tong)。在選(xuan)用(yong)閥(fa)(fa)門(men)(men)時，應根據閥(fa)(fa)門(men)(men)工(gong)(gong)作(zuo)特性曲線將閥(fa)(fa)內管(guan)(guan)(guan)路系統(tong)設計(ji)流量(liang)取(qu)在閥(fa)(fa)門(men)(men)控制(zhi)流量(liang)范圍(wei)的(de)最佳(jia)工(gong)(gong)作(zuo)區域內偏(pian)大側較(jiao)(jiao)好。選(xuan)取(qu)閥(fa)(fa)門(men)(men)口(kou)徑過小，使閥(fa)(fa)門(men)(men)在其控制(zhi)流量(liang)范圍(wei)的(de)高端(duan)工(gong)(gong)作(zuo)，極易(yi)產生噪(zao)聲。選(xuan)取(qu)閥(fa)(fa)門(men)(men)口(kou)徑過大，使閥(fa)(fa)門(men)(men)在其控制(zhi)流量(liang)范圍(wei)的(de)低端(duan)工(gong)(gong)作(zuo)，系統(tong)流量(liang)變化范圍(wei)過大，易(yi)造(zao)成閥(fa)(fa)外管(guan)(guan)(guan)路系統(tong)水力(li)失調，同(tong)時也造(zao)成經濟上(shang)的(de)浪費。一般閥(fa)(fa)門(men)(men)口(kou)徑較(jiao)(jiao)閥(fa)(fa)內管(guan)(guan)(guan)路系統(tong)接口(kou)管(guan)(guan)(guan)徑相等或(huo)小一號(hao)較(jiao)(jiao)好。

　　（4）壓差控制閥不能代替流量控制閥
　　使(shi)用(yong)(yong)壓(ya)差(cha)控(kong)制(zhi)(zhi)閥(fa)的(de)(de)(de)(de)目的(de)(de)(de)(de)是(shi)(shi)使(shi)熱用(yong)(yong)戶能夠(gou)在一(yi)定(ding)范圍內根(gen)(gen)據用(yong)(yong)熱需要調節流(liu)(liu)量(liang)(liang)(liang)，使(shi)用(yong)(yong)壓(ya)差(cha)控(kong)制(zhi)(zhi)閥(fa)的(de)(de)(de)(de)供(gong)(gong)(gong)(gong)熱系統(tong)(tong)是(shi)(shi)一(yi)個變流(liu)(liu)量(liang)(liang)(liang)系統(tong)(tong)。但目前多數(shu)供(gong)(gong)(gong)(gong)熱管(guan)網(wang)(wang)是(shi)(shi)根(gen)(gen)據供(gong)(gong)(gong)(gong)暖(nuan)的(de)(de)(de)(de)基(ji)本(ben)(ben)需要確定(ding)的(de)(de)(de)(de)，管(guan)網(wang)(wang)系統(tong)(tong)實際很難做到按需無(wu)限(xian)制(zhi)(zhi)供(gong)(gong)(gong)(gong)熱，勢必(bi)造成管(guan)網(wang)(wang)系統(tong)(tong)水(shui)力(li)(li)失調，特(te)別是(shi)(shi)在只安裝壓(ya)差(cha)控(kong)制(zhi)(zhi)閥(fa)而未(wei)裝熱表的(de)(de)(de)(de)供(gong)(gong)(gong)(gong)熱系統(tong)(tong)中，水(shui)力(li)(li)失調現象(xiang)尤為嚴重。在目前由(you)滿足基(ji)本(ben)(ben)供(gong)(gong)(gong)(gong)暖(nuan)需要向(xiang)按需供(gong)(gong)(gong)(gong)熱轉變的(de)(de)(de)(de)過渡階段，解決這(zhe)(zhe)個矛盾有兩種(zhong)方式(shi)(shi)(shi)：①加大管(guan)網(wang)(wang)流(liu)(liu)量(liang)(liang)(liang)；②在熱力(li)(li)入(ru)口處或(huo)在支干線(xian)上(shang)限(xian)制(zhi)(zhi)流(liu)(liu)量(liang)(liang)(liang)。限(xian)制(zhi)(zhi)流(liu)(liu)量(liang)(liang)(liang)的(de)(de)(de)(de)方法(fa)為設(she)(she)置(zhi)流(liu)(liu)量(liang)(liang)(liang)控(kong)制(zhi)(zhi)閥(fa)。流(liu)(liu)量(liang)(liang)(liang)控(kong)制(zhi)(zhi)閥(fa)可選用(yong)(yong)自(zi)力(li)(li)式(shi)(shi)(shi)流(liu)(liu)量(liang)(liang)(liang)控(kong)制(zhi)(zhi)閥(fa)，使(shi)管(guan)網(wang)(wang)能自(zi)動平衡(heng)流(liu)(liu)量(liang)(liang)(liang)。在每(mei)個熱力(li)(li)入(ru)口均設(she)(she)置(zhi)自(zi)力(li)(li)式(shi)(shi)(shi)流(liu)(liu)量(liang)(liang)(liang)控(kong)制(zhi)(zhi)閥(fa)，這(zhe)(zhe)種(zhong)方式(shi)(shi)(shi)費用(yong)(yong)較(jiao)高(gao)，因此較(jiao)少使(shi)用(yong)(yong)。另(ling)一(yi)種(zhong)方式(shi)(shi)(shi)是(shi)(shi)在支干線(xian)上(shang)設(she)(she)置(zhi)自(zi)力(li)(li)式(shi)(shi)(shi)流(liu)(liu)量(liang)(liang)(liang)控(kong)制(zhi)(zhi)閥(fa)。目前絕大多數(shu)熱力(li)(li)入(ru)口使(shi)用(yong)(yong)鎖閉式(shi)(shi)(shi)流(liu)(liu)量(liang)(liang)(liang)控(kong)制(zhi)(zhi)閥(fa)，這(zhe)(zhe)就要求在管(guan)網(wang)(wang)投運(yun)初期必(bi)須以人工(gong)(gong)方式(shi)(shi)(shi)做好初調節工(gong)(gong)作(zuo)，這(zhe)(zhe)項工(gong)(gong)作(zuo)費時(shi)、費力(li)(li)，較(jiao)為復雜，不易(yi)適應熱網(wang)(wang)工(gong)(gong)況的(de)(de)(de)(de)變化。但這(zhe)(zhe)是(shi)(shi)一(yi)種(zhong)經濟的(de)(de)(de)(de)保證供(gong)(gong)(gong)(gong)熱管(guan)網(wang)(wang)水(shui)力(li)(li)平衡(heng)的(de)(de)(de)(de)措施。

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