上海滬工閥門廠(集團)有限公司
1、閘閥的結構
閘閥閥體(ti)的結構決定與閥體(ti)與管道(dao)、閥體(ti)與閥蓋的連接(jie)(jie)、就制造方法而(er)言,有鑄造、鍛造、鍛焊、鑄焊以及管板焊接(jie)(jie)等幾種。
通常從經濟性考慮,公稱通經等于或大于 50mm 的閥門采用(yong)鑄(zhu)(zhu)造(zao),小于 50mm 的采用(yong)鍛(duan)造(zao)。但(dan)是(shi),隨著現(xian)代(dai)鑄(zhu)(zhu)、鍛(duan)技術的發(fa)(fa)展(zhan),已經(jing)逐步突破(po)這種限(xian)制。鍛(duan)造(zao)閥(fa)體已向(xiang)大口徑方向(xiang)發(fa)(fa)展(zhan),而鑄(zhu)(zhu)造(zao)閥(fa)體逐漸向(xiang)小口徑發(fa)(fa)展(zhan)。任何一種閘閥(fa)閥(fa)體即可鍛(duan)造(zao),也可鑄(zhu)(zhu)造(zao),應根據用(yong)戶要求以及制造(zao)廠擁有的制造(zao)手段而定(ding)。
2、閘閥閥體的流道
閘閥(fa)閥(fa)體的流(liu)道可(ke)分(fen)為,全(quan)通徑(jing)(jing)(jing)(jing)式(shi)(shi)和縮徑(jing)(jing)(jing)(jing)式(shi)(shi)兩種。流(liu)道孔徑(jing)(jing)(jing)(jing)與閥(fa)門(men)公(gong)(gong)稱通經,基本(ben)相(xiang)同(tong)的為全(quan)通徑(jing)(jing)(jing)(jing)式(shi)(shi);流(liu)通孔徑(jing)(jing)(jing)(jing)比閥(fa)門(men)公(gong)(gong)稱通經小的稱為縮徑(jing)(jing)(jing)(jing)式(shi)(shi)。縮徑(jing)(jing)(jing)(jing)形狀有均勻縮徑(jing)(jing)(jing)(jing)和費均勻縮徑(jing)(jing)(jing)(jing)兩種。流(liu)道呈(cheng)錐管形的即是一種非均勻縮徑(jing)(jing)(jing)(jing),這類閥(fa)門(men)入(ru)口端的孔徑(jing)(jing)(jing)(jing)基本(ben)上與公(gong)(gong)稱通徑(jing)(jing)(jing)(jing)相(xiang)同(tong),然后逐漸縮小,至閥(fa)座處(chu)縮小到(dao)最小。
采用縮(suo)徑(jing)(jing)(jing)(jing)(jing)(jing)式流(liu)道(無論是錐(zhui)管形(xing)(xing)非均勻縮(suo)徑(jing)(jing)(jing)(jing)(jing)(jing)或均勻縮(suo)徑(jing)(jing)(jing)(jing)(jing)(jing)),其優點是同(tong)一(yi)規格的(de)閥(fa)門(men),可減(jian)少閘板的(de)尺寸、啟閉力與(yu)力矩;缺(que)點是流(liu)阻增加,壓降(jiang)和能耗增大,所以縮(suo)孔(kong)不宜太(tai)大。對錐(zhui)管形(xing)(xing)縮(suo)徑(jing)(jing)(jing)(jing)(jing)(jing)來說,閥(fa)座的(de)內徑(jing)(jing)(jing)(jing)(jing)(jing)與(yu)公(gong)(gong)稱(cheng)通(tong)徑(jing)(jing)(jing)(jing)(jing)(jing)之比(bi),通(tong)常取 0.8~0.95。公(gong)(gong)稱(cheng)通(tong)徑(jing)(jing)(jing)(jing)(jing)(jing)小于 250mm 的(de)縮(suo)徑(jing)(jing)(jing)(jing)(jing)(jing)閥(fa)門(men),其閥(fa)座內徑(jing)(jing)(jing)(jing)(jing)(jing)一(yi)般比(bi)公(gong)(gong)稱(cheng)通(tong)徑(jing)(jing)(jing)(jing)(jing)(jing)降(jiang)低(di)一(yi)檔;公(gong)(gong)稱(cheng)通(tong)徑(jing)(jing)(jing)(jing)(jing)(jing)等(deng)于或大于 300mm 的(de)縮(suo)徑(jing)(jing)(jing)(jing)(jing)(jing)閥(fa)門(men),其閥(fa)座內徑(jing)(jing)(jing)(jing)(jing)(jing)一(yi)般比(bi)公(gong)(gong)稱(cheng)通(tong)徑(jing)(jing)(jing)(jing)(jing)(jing)降(jiang)低(di)二(er)檔。