短视频 | 一分钟认识【液环真空泵】的工作原理
<h1 style="color: black; text-align: left; margin-bottom: 10px;">液环泵的工作原理</h1>
<div style="color: black; text-align: left; margin-bottom: 10px;">
<div style="color: black; text-align: left; margin-bottom: 10px;">
<span style="color: black;">不支持的音频/视频格式</span>
<span style="color: black;">请试试<span style="color: black;">刷新</span></span>
</div>
重播
<div style="color: black; text-align: left; margin-bottom: 10px;">播放</div>
<span style="color: black;">00:00</span>
<span style="color: black;">/</span>
<span style="color: black;">00:00</span>
<span style="color: black;">直播</span>
<div style="color: black; text-align: left; margin-bottom: 10px;">
<div style="color: black; text-align: left; margin-bottom: 10px;">00:00</div>
</div>
<div style="color: black; text-align: left; margin-bottom: 10px;">进入全屏</div>
<div style="color: black; text-align: left; margin-bottom: 10px;">0</div>
<div style="color: black; text-align: left; margin-bottom: 10px;">点击按住可拖动视频</div>
</div>
<p style="font-size: 16px; color: black; line-height: 40px; text-align: left; margin-bottom: 15px;">液环泵属于容积泵,如图1所示。叶轮在泵腔内是偏心安装,当叶轮旋转时,会迫使工作液沿着泵腔内形成一个等厚的旋转液环,于是在两个相邻叶片、叶轮轮毂和液环内表面之间形成一个“气腔”,随着叶轮旋转,气腔在泵的吸气区的体积<span style="color: black;">逐步</span>增大,其内部压力下降,从而将气体吸入泵内,相反,气腔在排气区的体积则<span style="color: black;">逐步</span>变小,其内部压力<span style="color: black;">提升</span>,从而将气体排出。</p>
<div style="color: black; text-align: left; margin-bottom: 10px;"><img src="https://p3-sign.toutiaoimg.com/pgc-image/1597e842b0264852abf62cb17a566e91~noop.image?_iz=58558&from=article.pc_detail&lk3s=953192f4&x-expires=1728326467&x-signature=hMnExQh8EV3ipUvure3JFcyy5ws%3D" style="width: 50%; margin-bottom: 20px;">
<p style="font-size: 16px; color: black; line-height: 40px; text-align: left; margin-bottom: 15px;">图1液环泵剖面图</p>
</div>
<p style="font-size: 16px; color: black; line-height: 40px; text-align: left; margin-bottom: 15px;">液环泵有单级和双级两种,单级液环泵工作压力范围为1000~150mbar,入口压力<span style="color: black;">小于</span>150mbar时,抽速急剧下降,抽气效率较低。双级液环泵工作压力范围为1000~30mbar,在入口压力较低的<span style="color: black;">状况</span>下仍有<span style="color: black;">很强</span>抽速。</p>
<p style="font-size: 16px; color: black; line-height: 40px; text-align: left; margin-bottom: 15px;">液环泵的工作液有两个<span style="color: black;">功效</span>:一是用于密封,二是用于冷却。常用的工作液是水,<span style="color: black;">也</span><span style="color: black;">能够</span>用与工艺介质相适应的其他液体,如低粘度的油、乙二醇,以及其他工艺溶剂如甲苯、二甲苯、甲醇、乙醇、丙醇、丁醇和乙苯等。</p>
<h1 style="color: black; text-align: left; margin-bottom: 10px;">液环泵的优点</h1>
<p style="font-size: 16px; color: black; line-height: 40px; text-align: left; margin-bottom: 15px;"><strong style="color: blue;">液环泵有许多优点:</strong></p>
<p style="font-size: 16px; color: black; line-height: 40px; text-align: left; margin-bottom: 15px;">·操作简便、运动部件少,泵腔内<span style="color: black;">无</span>润滑油,不存在油的污染问题;</p>
<p style="font-size: 16px; color: black; line-height: 40px; text-align: left; margin-bottom: 15px;">·密封液的<span style="color: black;">选取</span>范围广;</p>
<p style="font-size: 16px; color: black; line-height: 40px; text-align: left; margin-bottom: 15px;">·既适合于抽可凝性蒸汽,又<span style="color: black;">能够</span>抽非可凝性气体;</p>
<p style="font-size: 16px; color: black; line-height: 40px; text-align: left; margin-bottom: 15px;">·<span style="color: black;">能够</span>抽出气流中的小液滴和微小颗粒;</p>
<p style="font-size: 16px; color: black; line-height: 40px; text-align: left; margin-bottom: 15px;">·<span style="color: black;">能够</span><span style="color: black;">选取</span><span style="color: black;">区别</span>的结构材料,标准<span style="color: black;">制品</span>是全铸铁和全316不锈钢,<span style="color: black;">也</span><span style="color: black;">能够</span>用合金钢20和哈氏族合金材料。</p>
<h1 style="color: black; text-align: left; margin-bottom: 10px;">液环泵的缺点</h1>
<p style="font-size: 16px; color: black; line-height: 40px; text-align: left; margin-bottom: 15px;">液环泵最大的缺点<span style="color: black;">便是</span>功耗比其他机械类的真空泵要大,<span style="color: black;">例如</span>滑阀泵消耗在密封、轴承、带动运动部件的功率占总功率的30%~40%,而液环泵在<span style="color: black;">以上</span>方面消耗的功率占总功率的60%~75%。</p>
<p style="font-size: 16px; color: black; line-height: 40px; text-align: left; margin-bottom: 15px;"><span style="color: black;">另一</span>,液环泵的极限压力受到密封液蒸气压的限制,例如液环泵用水<span style="color: black;">做为</span>密封液,其极限压力<span style="color: black;">便是</span>水在工作温度下的蒸汽压,当水温在20℃时,其极限压力<span style="color: black;">便是</span>3200Pa。</p>
<p style="font-size: 16px; color: black; line-height: 40px; text-align: left; margin-bottom: 15px;"><span style="color: black;">同期</span>,液环泵在低的入口压力下,会产生气蚀现象,<span style="color: black;">导致</span>气蚀的<span style="color: black;">原由</span>是:当泵的入口压力<span style="color: black;">小于</span>密封液的蒸气压时,密封液<span style="color: black;">快速</span>沸腾,并产生<span style="color: black;">海量</span>气泡,在气泡<span style="color: black;">提升</span>、破裂过程中会产生很大的冲击力,并从表面剥离少量金属,<span style="color: black;">倘若</span>这种气蚀<span style="color: black;">连续</span>时间很长,就会对泵<span style="color: black;">导致</span>严重损害。如图2所示。</p>
<div style="color: black; text-align: left; margin-bottom: 10px;"><img src="https://p3-sign.toutiaoimg.com/pgc-image/dc03b99ca5c44ae5af3f029cc47810a7~noop.image?_iz=58558&from=article.pc_detail&lk3s=953192f4&x-expires=1728326467&x-signature=4JGLw162m3Qt%2FpQiKEToXE06cYQ%3D" style="width: 50%; margin-bottom: 20px;">
<p style="font-size: 16px; color: black; line-height: 40px; text-align: left; margin-bottom: 15px;">图2液环泵的叶轮<span style="color: black;">因为</span>气蚀遭到损坏</p>
</div>
<p style="font-size: 16px; color: black; line-height: 40px; text-align: left; margin-bottom: 15px;">液环泵在低压下抽气量小、效率低,<span style="color: black;">况且</span>还产生气蚀现象,<span style="color: black;">意见</span>在液环泵的入口上增设一个大气喷射器,如图3所示,大气喷射器是喷射泵的一种类型,它利用液环泵工作时与大气压(<span style="color: black;">或</span>是液环泵的排气压力)之间的压差将气体吸入到工作喷嘴,并<span style="color: black;">得到</span>超音速的射流,在混合室内<span style="color: black;">导致</span>真空,从而将被抽气体吸入,两股气体混合后,经过扩压管再被液环泵吸入并排到泵外。</p>
<div style="color: black; text-align: left; margin-bottom: 10px;"><img src="https://p3-sign.toutiaoimg.com/pgc-image/02f8f2e5d4ff41e58b47175ab74434c3~noop.image?_iz=58558&from=article.pc_detail&lk3s=953192f4&x-expires=1728326467&x-signature=ZrnslKUZNwSRgvThjHPr2uoBsvU%3D" style="width: 50%; margin-bottom: 20px;">
<p style="font-size: 16px; color: black; line-height: 40px; text-align: left; margin-bottom: 15px;">图3液环泵+大气喷射器工作原理图</p>
</div>
<h1 style="color: black; text-align: left; margin-bottom: 10px;">机组</h1>
<p style="font-size: 16px; color: black; line-height: 40px; text-align: left; margin-bottom: 15px;">大气喷射器液环泵机组<span style="color: black;">重点</span>在较低工作压力或密封液温度较高<span style="color: black;">状况</span>下工作。喷射器吸入的气体<span style="color: black;">能够</span>是空气,<span style="color: black;">也</span><span style="color: black;">能够</span>用液环泵排出的气体<span style="color: black;">做为</span>大气喷射器的驱动气体。<span style="color: black;">尤其</span>是罗茨液环机组,<span style="color: black;">倘若</span>在液环泵入口配上大气喷射器,如图4所示,既<span style="color: black;">能够</span><span style="color: black;">加强</span>机组的极限真空,又可以降低罗茨泵的压缩比,在罗茨液环机组进入极限压力时,罗茨泵不会过热,液环泵<span style="color: black;">也</span>不会产生气蚀。</p>
<div style="color: black; text-align: left; margin-bottom: 10px;"><img src="https://p3-sign.toutiaoimg.com/pgc-image/42571e05eb20458aab889c97e593b0b6~noop.image?_iz=58558&from=article.pc_detail&lk3s=953192f4&x-expires=1728326467&x-signature=aq112cBExLE64Ztl3o8JG%2FYfvlY%3D" style="width: 50%; margin-bottom: 20px;">
<p style="font-size: 16px; color: black; line-height: 40px; text-align: left; margin-bottom: 15px;">图4 罗茨泵/大气喷射器/液环泵机组</p>
</div>
<p style="font-size: 16px; color: black; line-height: 40px; text-align: left; margin-bottom: 15px;">本文文字及<span style="color: black;">照片</span>摘自《适用于化工工业的真空泵》一文,原文<span style="color: black;">发布</span>于《真空》杂志2020年第2期,作者:姜燮昌。</p>
感谢楼主的分享!我学到了很多。
页:
[1]