發布時間:2026-04-21 09:37:24 人氣:266623 來源:
1.泵自身構體引起的振動
離心泵是由軸、軸承及安裝在軸上的葉輪,驅動裝置(如電機、汽輪機、燃氣輪機驅動等)構成的。泵軸振動、轉子不平衡、驅動軸不同心、軸承缺陷、葉片及軸上其他部件鬆動等,都有可能引起振動。使用振動監測裝置可以測得單個振動頻率,用於分析這些振源類型。
裝在泵軸上的秭歸機械密封有不同的振動頻率,低時可在泵轉速以下,高時可達每秒數千次。如果振動頻率剛好與秭歸機械密封中(zhong)的(de)彈(dan)性(xing)元(yuan)件(jian)固(gu)有(you)頻(pin)率(lv)相(xiang)同(tong),就(jiu)可(ke)造(zao)成(cheng)摩(mo)擦(ca)副(fu)磨(mo)損(sun)加(jia)快(kuai)或(huo)疲(pi)勞(lao)損(sun)傷(shang)。當(dang)然(ran),這(zhe)種(zhong)損(sun)傷(shang)還(hai)有(you)其(qi)他(ta)因(yin)素(su)。所(suo)以(yi)在(zai)設(she)計(ji)或(huo)選(xuan)型(xing)時(shi),必(bi)須(xu)保(bao)證(zheng)可(ke)預(yu)測(ce)的(de)共(gong)振(zhen)頻(pin)率(lv)不(bu)要(yao)與(yu)激(ji)勵(li)頻(pin)率(lv)重(zhong)合(he),應(ying)采(cai)取(qu)可(ke)靠(kao)減(jian)振(zhen)措(cuo)施(shi),設(she)計(ji)的(de)臨(lin)界(jie)轉(zhuan)速(su)不(bu)能(neng)與(yu)工(gong)作(zuo)轉(zhuan)速(su)相(xiang)距(ju)太(tai)近(jin);在操作溫度下,將安裝誤差減至最小,因為這些誤差會導致密封彈性裝置的位移;轉子要充分平衡;垂直安裝軸上的軸承,其承受的載荷應使滾動件打滑的可能性減至最小。

需要說明的是:
(1)秭歸機械密封的彈性元件(包括單彈簧和多彈簧),彈簧本身可承受大部分振動載荷,輔助密封也有一定減振效果,如楔形環、O形圈、膨脹石墨等;
(2)對於支承在彈簧上的質量較小的密封,如石墨密封環的結構,其固有頻率相對較大;
(3)zhichengzaididanxingdanhuangshangdezhiliangjiaodademifeng,qiguyoupinlvxiangduijiaoxiao,qieqiangtineiyalijiaodiqingkuangxiachuxiangongzhenkenengxingjiaoxiao,jinshubowenguanxingmifenggenjubutongdeqiangdusheji,qidanxingyougaoyoudi;
(4)由於沒有滑動的輔助密封,所以依靠密封端麵上的液膜或液體減振,當然也可以設計帶滑動的輔助密封,提高它的穩定性和剛性;
(5)大多數秭歸機械密封的固有頻率都遠高於正常的操作轉速,對於金屬波紋管型秭歸機械密封,要特別注意避免軸向共振,異常振動會加劇波紋管疲勞斷裂。如泵軸上軸承的軸向遊隙調整不當就容易出現這現象。
另(ling)外(wai)根(gen)據(ju)密(mi)封(feng)環(huan)材(cai)料(liao)的(de)不(bu)同(tong),特(te)別(bie)是(shi)當(dang)采(cai)用(yong)碳(tan)化(hua)鎢(wu)類(lei)高(gao)密(mi)度(du)材(cai)料(liao)時(shi),更(geng)應(ying)注(zhu)意(yi)共(gong)振(zhen)問(wen)題(ti)。因(yin)此(ci),當(dang)支(zhi)承(cheng)在(zai)彈(dan)性(xing)元(yuan)件(jian)的(de)密(mi)封(feng)環(huan)需(xu)要(yao)采(cai)用(yong)硬(ying)質(zhi)材(cai)料(liao)時(shi),條(tiao)件(jian)允(yun)許(xu)情(qing)況(kuang)下(xia)一(yi)般(ban)都(dou)選(xuan)用(yong)密(mi)度(du)相(xiang)對(dui)較(jiao)低(di)的(de)碳(tan)化(hua)矽(gui)、陶瓷等材料。
2.在正常及擾動條件下產生的振動
泵運行時,其轉子及秭歸機械密封huishoudaoyelizhendongyingxiang,dangliuliangfashengbianhuashi,yelunrukouchuyetihuichanshengbodong,ruobushizaizuijiaxiaolvxiayunxing,yelunrukoujikuoyaguanchudeliutiyatouhuizengda。diyuhuogaoyuzuijiaxiaolvdiandeliuliangshi,huoshusongjiezhiwufadadaobengdeqishiyuliangshi,doukenengchanshengqishixianxiang,zemifengjizhenjiugengmingxian。lingwai,rukouchujiezhideliudonghaihuishoudaobengneijiezhizixunhuandeganrao。
zhuanzixitongdezhendongjizuoyongzaimifengshangyalizhuangkuangdebianhua,suoyinqidezhendongdezhenfuhepinlvshisuijide。zaishejixitonghexuanzebengshi,yingshiqizaizuijiaxiaolvzhuangtaixiayunxing,baozhengbengzaifuyaqingkuangxiagongzuowending,jibaozhengbengyouzugouqishiyuliang,fangzhijiezhizai秭歸機械密封的表麵氣蝕產生激振。
3.溫度及壓力變化使泵變形而產生的振動
泵運行過程中,溫度發生變化時,泵的各部件會產生熱變形,這時泵相對於驅動裝置會發生偏移,引起秭歸機械密封zhendong。ciwai,wenduduiketihezhuanzideyingxiangchengdubuyiyang,yibanqingkuangxia,zhuanziyaobiketibianhuaxunsu。dangyunxingwendubodongshi,mifengchuleyaochengshoubujiancuoweichanshengdezhendongwai,haiyaochengshoudipinlvdazhenfudezhendong。youyu秭歸機械密封的一側固定在殼體上,而另一端固定在轉軸上,所以必須有吸收這兩種不同振動的能力。
壓力也能使泵體變形,從而多秭歸機械密封產生幹擾。當密封腔內壓力發生變化時,作用在密封端麵上的載荷也會隨之發生變化,從而產生突變載荷引起振動。
4.製造安裝原因產生的振動
mifengduanmiancucaoduguoda,bunengbaozhenghenhaodetiehexing,mifengdewendingxingjiuhuishoudaoyingxiang,yingxiangchengdubujinqujueyumifengdejutijiegou,erqiequjueyumifengyunxingcanshu。mifengmeixuanzhuanyizhouqibuchanghuandouyaozuoxiangyingdeyunxing,congerbaozhengmifengduanmiandetiehexing。duiyuhuadongfuzhumifengjian,ruO形xing圈quan或huo楔xie形xing環huan,密mi封feng麵mian上shang的de載zai荷he沿yan圓yuan周zhou變bian化hua,應ying盡jin量liang防fang止zhi不bu受shou載zai荷he的de一yi側ce發fa生sheng泄xie漏lou,受shou載zai荷he的de一yi側ce出chu現xian過guo度du磨mo損sun的de現xian象xiang。泄xie漏lou會hui使shi流liu體ti的de雜za粒li滲shen到dao端duan麵mian液ye膜mo中zhong,從cong而er加jia速su密mi封feng端duan麵mian磨mo損sun。
mifengjianzaijiagongguochengzhong,yibanbunengyongjixiefangfajiayipingheng。zaishejizhongyaojinliangjianshaobupinghengyinsu,rudandanhuangjiuhuizaochengbupingheng,tebieshizaizhizaocucaodedonghuanhuoxiangmifengjianchuandidedonglijuyou“尾隨脈衝”情況時,更應注意不平衡問題。
zaicaiyongneizhuangshijixiemifengshi,zuoyongzaimifengshangdechongjilichangchangshiyoubengsongjiezhidezixunhuanzaochengde。weiquebaomifengxingneng,zixunhuanyetiyingcongliangmifengduandewaicetongguo。ruoliuliangguoda,zezuoyongzaimifenghuanshangdechongjilikenenghuishimifengduancuowei,qihouguoziranshizhendong。
為減輕振動的影響,可以使自循環流體,由切向入口;如ru有you可ke能neng,循xun環huan流liu量liang可ke以yi通tong過guo密mi封feng腔qiang內nei襯chen套tao的de配pei合he間jian隙xi加jia以yi控kong製zhi,或huo者zhe將jiang密mi封feng腔qiang內nei的de吸xi入ru管guan和he排pai出chu管guan反fan接jie,使shi流liu向xiang改gai變bian而er形xing成cheng逆ni循xun環huan。後hou一yi種zhong方fang法fa常chang在zai立li式shi泵beng中zhong采cai用yong,因yin為wei它ta同tong時shi解jie決jue了le密mi封feng腔qiang上shang部bu的de排pai氣qi問wen題ti;但是,這常被人們所忽視,甚至在臥式泵的設計中,密封腔內由於逆循環產生的壓差而會顯著改善密封效果。