可(ke)變彈簧支吊架的核(he)心(xin)部件是一個被(bei)(bei)控制(zhi)的圓柱(zhu)彈簧,當被(bei)(bei)支承(cheng)管道發(fa)生豎向位(wei)移時,會帶動圓柱(zhu)彈簧的控制(zhi)板(ban)使彈簧被(bei)(bei)壓縮(suo)或被(bei)(bei)拉長。
國家標(biao)(biao)準GB 10182共給出(chu)了A、B、C、D、E、F、G七種標(biao)(biao)準形式,與HG/T 20644標(biao)(biao)準是一致的,如圖9-37所示(shi):A型(xing)(xing)(xing)(xing)為(wei)上螺紋懸(xuan)吊型(xing)(xing)(xing)(xing);B型(xing)(xing)(xing)(xing)為(wei)單(dan)耳懸(xuan)吊型(xing)(xing)(xing)(xing);C型(xing)(xing)(xing)(xing)為(wei)雙耳懸(xuan)吊型(xing)(xing)(xing)(xing);D型(xing)(xing)(xing)(xing)為(wei)上調節擱置(zhi)型(xing)(xing)(xing)(xing);E型(xing)(xing)(xing)(xing)為(wei)下調節擱置(zhi)型(xing)(xing)(xing)(xing);F型(xing)(xing)(xing)(xing)為(wei)支承擱置(zhi)型(xing)(xing)(xing)(xing);G型(xing)(xing)(xing)(xing)為(wei)并聯懸(xuan)吊型(xing)(xing)(xing)(xing)。它們的適用情況分述(shu)如下。
A、B、C三種形式(shi)均為懸(xuan)吊(diao)(diao)型可變彈(dan)簧吊(diao)(diao)架,上端通(tong)過(guo)吊(diao)(diao)桿(gan)與(yu)生根部(bu)件相連(lian),下端則(ze)通(tong)過(guo)可調螺母和吊(diao)(diao)桿(gan)與(yu)附管部(bu)件相連(lian)。三者所不同的(de)(de)是上端與(yu)吊(diao)(diao)桿(gan)的(de)(de)連(lian)接(jie)方式(shi)不同。
D型(xing)(xing)和(he)E型(xing)(xing)為擱(ge)置型(xing)(xing)可(ke)變(bian)彈(dan)簧(huang)吊架,即其底座擱(ge)置于(yu)支承(cheng)(cheng)梁或(huo)平臺梁的(de)上面(mian),下端則通過可(ke)調(diao)螺母和(he)吊桿與附管部件(jian)相(xiang)連。與A、B、C三種形式(shi)相(xiang)比(bi),D型(xing)(xing)、E型(xing)(xing)更容易使操作(zuo)人員接近,以便(bian)從(cong)彈(dan)簧(huang)支吊架的(de)刻度指示板上了解支承(cheng)(cheng)點(dian)的(de)位(wei)移情況,并(bing)與計算值進行對比(bi)。D型(xing)(xing)和(he)E型(xing)(xing)僅(jin)僅(jin)是吊桿與彈(dan)簧(huang)連接的(de)方式(shi)不同,前者(zhe)便(bian)于(yu)隨時(shi)調(diao)節彈(dan)簧(huang)荷載(zai),而后者(zhe)則對防(fang)止雨水進入彈(dan)簧(huang)支架有(you)利。
F型為支(zhi)托型可(ke)變(bian)(bian)彈簧(huang)支(zhi)架,它與(yu)前面幾(ji)種吊架形式相比(bi)剛(gang)性較大(da),但當(dang)管道在支(zhi)承點(dian)(dian)同時(shi)有橫(heng)向位(wei)移時(shi),會(hui)因摩擦力的作(zuo)用使(shi)它發生傾斜甚至失穩。為此,一些(xie)生產廠則開發出(chu)了帶滾(gun)輪的支(zhi)托型可(ke)變(bian)(bian)彈簧(huang)支(zhi)架,當(dang)管子在支(zhi)承點(dian)(dian)的橫(heng)向位(wei)移大(da)于6mm時(shi),應考慮選用帶滾(gun)輪的支(zhi)托型可(ke)變(bian)(bian)彈簧(huang)支(zhi)架。
G型為并聯懸(xuan)吊(diao)型可變(bian)彈簧(huang)(huang)吊(diao)架(jia),它常用(yong)于生根(gen)條件不(bu)太合適,或彈簧(huang)(huang)承載過大而需要并聯設置時(shi)。當然,選用(yong)A~E中(zhong)任(ren)何一種的兩個可變(bian)彈簧(huang)(huang)支(zhi)吊(diao)架(jia)并聯也可以(yi),應視(shi)方便而定(ding)。
可變(bian)彈簧(huang)支吊架(jia)標準系列中都給(gei)出(chu)了它們的對應關系數據表,選用時查(cha)表即可。
當管系中某點的垂(chui)直位移量(liang)較(jiao)大(da)時(shi),從(cong)標(biao)準(zhun)彈(dan)簧(huang)支(zhi)吊(diao)(diao)架(jia)表中可能(neng)已(yi)選(xuan)不(bu)到(dao)合適的彈(dan)簧(huang)支(zhi)吊(diao)(diao)架(jia),即要(yao)(yao)(yao)么找不(bu)到(dao)最大(da)工(gong)作(zuo)位移能(neng)滿足荷(he)載要(yao)(yao)(yao)求的標(biao)準(zhun)系列,要(yao)(yao)(yao)么因剛度較(jiao)大(da)而使荷(he)載變化率超出標(biao)準(zhun)要(yao)(yao)(yao)求,此(ci)時(shi)可考慮(lv)采用串聯可變彈(dan)簧(huang)支(zhi)吊(diao)(diao)架(jia)。如果彈(dan)簧(huang)支(zhi)吊(diao)(diao)點的垂(chui)直位移比較(jiao)大(da),選(xuan)用兩個可變彈(dan)簧(huang)串聯仍(reng)不(bu)能(neng)滿足要(yao)(yao)(yao)求時(shi),可以串聯更多的可變彈(dan)簧(huang),但此(ci)時(shi)應考慮(lv)是否(fou)改用恒力彈(dan)簧(huang)更合適。
當管(guan)(guan)道支(zhi)(zhi)承(cheng)點(dian)的(de)荷載(zai)超出標(biao)準可變(bian)彈簧(huang)支(zhi)(zhi)吊架(jia)(jia)的(de)最大(da)允許荷載(zai)時,或(huo)者受支(zhi)(zhi)承(cheng)條(tiao)件(jian)(如豎管(guan)(guan)支(zhi)(zhi)承(cheng))、生根條(tiao)件(jian)等限(xian)制不宜采(cai)用單個可變(bian)彈簧(huang)支(zhi)(zhi)吊架(jia)(jia)進行(xing)支(zhi)(zhi)承(cheng)時,可選(xuan)用兩個或(huo)兩個以上的(de)可變(bian)彈簧(huang)支(zhi)(zhi)吊架(jia)(jia)并聯支(zhi)(zhi)承(cheng)。
可變彈(dan)(dan)簧(huang)支吊架串(chuan)聯安裝時(shi),應選用(yong)(yong)最(zui)大荷(he)載相同(tong)的(de)彈(dan)(dan)簧(huang),每(mei)個彈(dan)(dan)簧(huang)的(de)壓(ya)縮量(liang)應按(an)其工作位移范圍比例進行(xing)分配。可變彈(dan)(dan)簧(huang)支吊架并聯安裝時(shi),應選用(yong)(yong)同(tong)一型號的(de)彈(dan)(dan)簧(huang),每(mei)個彈(dan)(dan)簧(huang)承受的(de)荷(he)載應按(an)并聯彈(dan)(dan)簧(huang)個數(shu)平均分配。