性色A码一区二区三区天美传媒_广东少妇大战黑人34厘米视频_国产又爽又粗又猛的视频_黑人巨鞭大战中国妇女

HXF-4防(fang)火防(fang)爆呼(hu)(hu)吸(xi)(xi)閥(fa)類似于單向(xiang)(xiang)止逆(ni)閥(fa),它只能向(xiang)(xiang)外(wai)呼(hu)(hu)氣(qi),不能向(xiang)(xiang)內(nei)吸(xi)(xi)氣(qi),當系(xi)(xi)統(tong)內(nei)壓(ya)力升高時,氣(qi)體便(bian)經過向(xiang)(xiang)外(wai)放空(kong)(kong),保證系(xi)(xi)統(tong)的(de)(de)壓(ya)力恒(heng)定。一般(ban)它被用(yong)在常壓(ya)或低(di)壓(ya)貯(zhu)罐上(shang)。焦炭(tan)塔的(de)(de)呼(hu)(hu)吸(xi)(xi)閥(fa)有兩個用(yong)處：放水(shui)時吸(xi)(xi)氣(qi)以利(li)塔內(nei)存水(shui)順(shun)利(li)放出,呼(hu)(hu)氣(qi)蒸汽(qi)趕(gan)空(kong)(kong)氣(qi)時,用(yong)以放凈空(kong)(kong)氣(qi),脫水(shui)放汽(qi)時,用(yong)以檢(jian)查塔內(nei)是(shi)否為(wei)正壓(ya)。