Parker派克RS系列先導式溢流閥,Parker派克RS系列先導式溢流閥具有堅固的閥體,它是由一個DIN標準的NG25筒形插裝閥作為主級以及螺紋式插裝閥作為先導級所組成的。通過安裝在閥體上的電磁換向閥可進行電控卸壓。可在訂貨代號中常開或常閉的換向開關功能。 注意事(shi)項(xiang) 噪聲和振動 液壓(ya)(ya)裝(zhuang)置中容易產(chan)(chan)生(sheng)(sheng)(sheng)噪(zao)聲(sheng)(sheng)的(de)元(yuan)件(jian)一般(ban)認為是(shi)泵(beng)和閥(fa)(fa),閥(fa)(fa)中又以(yi)溢流(liu)(liu)閥(fa)(fa)和電磁(ci)換向(xiang)閥(fa)(fa)等為主。產(chan)(chan)生(sheng)(sheng)(sheng)噪(zao)聲(sheng)(sheng)的(de)因(yin)素很多(duo)。溢流(liu)(liu)閥(fa)(fa)的(de)噪(zao)聲(sheng)(sheng)有流(liu)(liu)速(su)聲(sheng)(sheng)和機(ji)械(xie)聲(sheng)(sheng)二種。流(liu)(liu)速(su)聲(sheng)(sheng)中主要由油液振動、空穴以(yi)及液壓(ya)(ya)沖擊等原(yuan)(yuan)因(yin)產(chan)(chan)生(sheng)(sheng)(sheng)的(de)噪(zao)聲(sheng)(sheng)。機(ji)械(xie)聲(sheng)(sheng)中主要由閥(fa)(fa)中零件(jian)的(de)撞(zhuang)擊和磨(mo)擦等原(yuan)(yuan)因(yin)產(chan)(chan)生(sheng)(sheng)(sheng)的(de)噪(zao)聲(sheng)(sheng)。 (1)壓力(li)不(bu)均勻引起的噪聲 先(xian)導(dao)型溢流閥(fa)(fa)(fa)的(de)導(dao)閥(fa)(fa)(fa)部分(fen)是一(yi)個易振部位如圖3所(suo)示。在高壓情況下溢流時(shi),導(dao)閥(fa)(fa)(fa)的(de)軸(zhou)向(xiang)開(kai)口很小,僅0.003~0.006厘米(mi)。過流面(mian)積很小,流速很高,可達200米(mi)/秒,易引起壓力分(fen)布不(bu)(bu)均勻,使錐閥(fa)(fa)(fa)徑向(xiang)力不(bu)(bu)平(ping)衡而產生(sheng)振動。另外錐閥(fa)(fa)(fa)和錐閥(fa)(fa)(fa)座加工時(shi)產生(sheng)的(de)橢圓度、導(dao)閥(fa)(fa)(fa)口的(de)臟物粘住(zhu)及調壓彈簧變形(xing)等,也會(hui)引起錐閥(fa)(fa)(fa)的(de)振動。所(suo)以一(yi)般認(ren)為導(dao)閥(fa)(fa)(fa)是發生(sheng)噪聲的(de)振源部位。 由(you)于有彈(dan)性元件(jian)(彈(dan)簧(huang))和(he)運動(dong)(dong)質(zhi)量(錐閥(fa))的存在,構成了一(yi)(yi)個產生振蕩的條件(jian),而導(dao)閥(fa)前腔又(you)起了一(yi)(yi)個共(gong)振腔的作用,所以(yi)錐閥(fa)發生振動(dong)(dong)后易引起整個閥(fa)的共(gong)振而發出噪聲,發生噪聲時(shi)一(yi)(yi)般多伴隨有劇烈的壓力跳(tiao)動(dong)(dong)。 (2)空穴產(chan)生的噪聲 當(dang)由于各種(zhong)原因,空氣(qi)被吸入(ru)油液(ye)(ye)中,或者在(zai)(zai)油液(ye)(ye)壓(ya)(ya)(ya)力低(di)于大(da)(da)氣(qi)壓(ya)(ya)(ya)時,溶解在(zai)(zai)油液(ye)(ye)中的部分空氣(qi)就會析出形成(cheng)氣(qi)泡,這些(xie)氣(qi)泡在(zai)(zai)低(di)壓(ya)(ya)(ya)區(qu)(qu)時體(ti)(ti)(ti)(ti)積較大(da)(da),當(dang)隨油液(ye)(ye)流到高壓(ya)(ya)(ya)區(qu)(qu)時,受到壓(ya)(ya)(ya)縮,體(ti)(ti)(ti)(ti)積突(tu)然(ran)變(bian)(bian)小(xiao)或氣(qi)泡消失;反之,如在(zai)(zai)高壓(ya)(ya)(ya)區(qu)(qu)時體(ti)(ti)(ti)(ti)積本(ben)來(lai)較小(xiao),而當(dang)流到低(di)壓(ya)(ya)(ya)區(qu)(qu)時,體(ti)(ti)(ti)(ti)積突(tu)然(ran)增大(da)(da),油中氣(qi)泡體(ti)(ti)(ti)(ti)積這種(zhong)急(ji)速(su)改變(bian)(bian)的現象。氣(qi)泡體(ti)(ti)(ti)(ti)積的突(tu)然(ran)改變(bian)(bian)會產(chan)生噪(zao)聲,又由于這一過(guo)程發生在(zai)(zai)瞬間,將引起局部液(ye)(ye)壓(ya)(ya)(ya)沖擊而產(chan)生振動。先導(dao)式溢流閥(fa)的導(dao)閥(fa)口和主閥(fa)口,油液(ye)(ye)流速(su)和壓(ya)(ya)(ya)力的變(bian)(bian)化很(hen)(hen)大(da)(da),很(hen)(hen)容易(yi)出現空穴現象,由此而產(chan)生噪(zao)聲和振動。 (3)液壓(ya)沖擊產生的噪聲 先(xian)導式(shi)溢流(liu)閥(fa)在(zai)卸(xie)荷(he)時(shi),會因(yin)液(ye)壓(ya)(ya)(ya)(ya)(ya)回路的(de)(de)(de)壓(ya)(ya)(ya)(ya)(ya)力急驟下降(jiang)而(er)發(fa)生壓(ya)(ya)(ya)(ya)(ya)力沖(chong)(chong)擊(ji)(ji)噪(zao)(zao)聲(sheng)。愈是(shi)高(gao)壓(ya)(ya)(ya)(ya)(ya)大容量的(de)(de)(de)工作條件(jian),這種(zhong)沖(chong)(chong)擊(ji)(ji)噪(zao)(zao)聲(sheng)愈大,這是(shi)由于溢流(liu)閥(fa)的(de)(de)(de)卸(xie)荷(he)時(shi)間很(hen)短而(er)產(chan)生液(ye)壓(ya)(ya)(ya)(ya)(ya)沖(chong)(chong)擊(ji)(ji)所(suo)致在(zai)卸(xie)荷(he)時(shi),由于油流(liu)速急劇變(bian)化,引(yin)起壓(ya)(ya)(ya)(ya)(ya)力突變(bian),造成壓(ya)(ya)(ya)(ya)(ya)力波(bo)的(de)(de)(de)沖(chong)(chong)擊(ji)(ji)。壓(ya)(ya)(ya)(ya)(ya)力波(bo)是(shi)一個小的(de)(de)(de)沖(chong)(chong)擊(ji)(ji)波(bo),本(ben)身產(chan)生的(de)(de)(de)噪(zao)(zao)聲(sheng)很(hen)小,但隨油液(ye)傳到(dao)系統(tong)(tong)中(zhong),如果(guo)同任何(he)一個機(ji)械(xie)零件(jian)發(fa)生共振,就(jiu)可能(neng)加大振動和(he)增強噪(zao)(zao)聲(sheng)。所(suo)以(yi)在(zai)發(fa)生液(ye)壓(ya)(ya)(ya)(ya)(ya)沖(chong)(chong)擊(ji)(ji)噪(zao)(zao)聲(sheng)時(shi),一般多(duo)伴(ban)有(you)系統(tong)(tong)振 動。 (4)機械噪聲 先導(dao)式溢流閥(fa)發出的(de)機械噪聲,一般來自零件(jian)的(de)撞擊和由于加工(gong)誤差等產生(sheng)的(de)零件(jian)磨擦。 在(zai)先(xian)導型溢(yi)流(liu)(liu)閥(fa)發出的噪聲中,有時會有機械性的高(gao)頻(pin)振(zhen)動(dong)聲,一(yi)(yi)般稱它為自激(ji)振(zhen)動(dong)聲。這(zhe)是主閥(fa)和導閥(fa)因高(gao)頻(pin)振(zhen)動(dong)而發生的聲音。它的發生率(lv)與(yu)回(hui)油管道(dao)的配(pei)置(zhi)、流(liu)(liu)量、壓力、油溫(粘度(du))等因素有關。一(yi)(yi)般情況下(xia),管道(dao)口(kou)徑(jing)小、流(liu)(liu)量少、壓力高(gao)、油液粘度(du)低,自激(ji)振(zhen)動(dong)發生率(lv)就高(gao)。 美國PARKER溢流閥型號: RS10M17L4SN1JW RS10M17T4SN1JW RS10M25S1SN1JW RS10M35T4SN1JW RS10M35T4SN1JWS RS10R17T4SN1JW RS10R25T4SN1YW RS10R25T4SN9JW RS10R35T4SN1JW RS10R35T4SN9JW RS25M07T4SN1JW RS25M25T4SN1JW RS25M35T4SN1JW RS25M35T4SN1UW RS25M35T4SN9JW RS25R17T4SN1JW RS25R25T4SN1JW RS25R25T4SN1UW RS25R25T4SN1YW RS25R25T4SN9JW RS25R35T4SN1GW RE10R17T4SN1G0M46 RS10M17L4SN1JW40 RS10M17T4SN1JW40 RS10M25S1SN1JW40 RS10M35T4SN1JW40 RS10M35T4SN1JWT40 RS10R17T4SN1JW40 RS10R25T4SN1YW45 RS10R25T4SN9JW40 RS10R35T4SN1JW40 RS10R35T4SN9JW40 RS25M07T4SN1JW40 RS25M25T4SN1JW40 RS25M35T4SN1JW40 RS25M35T4SN1UW40 RS25M35T4SN9JW40 RS25R17T4SN1JW40 RS25R25T4SN1JW40 RS25R25T4SN1UW40 RS25R25T4SN1YW40 RS25R25T4SN9JW40 RS25R35T4SN1GW40 RE10R17T4SN1G0M RS10M17L4SN1JW RS10M17S4SN1JW RS10M25S1SN1JW RS10M35S4SN1JW RS10M35S4SN1JWS RS10R17S4SN1JW RS10R25S4SN1YW RS10R25S4SN9JW RS10R35S4SN1JW RS10R35S4SN9JW RS25M07S4SN1JW RS25M25S4SN1JW RS25M35S4SN1JW RS25M35S4SN1UW RS25M35S4SN9JW RS25R17S4SN1JW RS25R25S4SN1JW RS25R25S4SN1UW RS25R25S4SN1YW RS25R25S4SN9JW RS25R35S4SN1GW RE10R17T4SN1G0M46 RS10M17L4SN1JW40 RS10M17S4SN1JW40 RS10M25S1SN1JW40 RS10M35S4SN1JW40 RS10M35S4SN1JWS40 RS10R17S4SN1JW40 RS10R25S4SN1YW45 RS10R25S4SN9JW40 RS10R35S4SN1JW40 RS10R35S4SN9JW40 RS25M07S4SN1JW40 RS25M25S4SN1JW40 RS25M35S4SN1JW40 RS25M35S4SN1UW40 RS25M35S4SN9JW40 RS25R17S4SN1JW40 RS25R25S4SN1JW40 RS25R25S4SN1UW40 RS25R25S4SN1YW40 RS25R25S4SN9JW40 RS25R35S4SN1GW40 |