1. <strong id="seay1"></strong>
  2. <tfoot id="seay1"><dfn id="seay1"></dfn></tfoot>

  3. 久久综合网欧美色妞网,国产强伦姧在线观看无码,免费女人18毛片a毛片视频,成人嫩草研究院久久久精品,偷窥 自由 网络 视频,丰满人妻一区二区三区,久久久中文字幕av无码,久久精品国产亚洲成人AV未满十八站

    Gas cut-off valve

    Dateline:2014-11-30    Hits:

    Natural gas cut-off valve is a cut-off valve. Common pressure around 16mpa. Mainlyused in gas, oil and gas, field. The main domestic well-known manufacturers have the right to work in Shanghai valve equipment Co., Ltd and Hunan emerging HydropowerEquipment Co., ltd..

    Valve is closed parts (valve) moving along the centerline of the valve seat. According to this mobile form of valve, valve seat through the mouth of the change isproportional to the valve stroke. Because of the valve stem to open or close the relatively short trip, and have very reliable cutting off function, and because changes in the valve seat and the valve stroke is proportional, is very suitable for theadjustment of flow. Therefore, this type of valve is suitable for cutting off or adjust the throttle use.

    The most obvious advantage of cut-off valve:

    (L) in the opening and closing process, because the valve flap and valve sealing surface friction than the gate is small, and therefore wear.

    (2) generally only open seat height channel diameter L / 4, so much smaller than the gate.

    (3) usually in the valve body and the valve flap is only one sealing surface, and thus comparison of manufacturing processes, ease of maintenance. However, valve defects can not be ignored. Its main drawback is the relatively large flow resistance coefficient, the resulting pressure loss, especially in the hydraulic device, this pressure loss is particularly evident.


    手機網站

    主站蜘蛛池模板: 国产黑色丝袜在线看片不卡顿 | 国产精品七七在线播放| 777米奇影视第四色| 91久久性奴调教国产免费| 免费人成视频在线播放| 中国熟女仑乱hd| 国产一国产一级无码秋霞电影院| 国产又黄又爽又不遮挡视频 | 91久久国产成人免费观看| 天天躁天天狠天天透| 国产区精品福利在线熟女| 中文无码乱人伦中文视频在线| 国产成人精品综合久久久| 亚洲精品在线视频自拍| 鲁丝无码一区二区三区| 国产精品久久免费看| 日韩成人动漫在线观看| 久久婷婷五月综合国产尤物app| 婷婷久久综合九色综合88| 99久久精品免费看国产一区二区三区 | 人妻去按摩店被黑人按中出| 18禁网站久久精品| 国产精品嫩草影院永久| 少妇午夜啪爽嗷嗷叫视频| 中文一级国产特级毛片视频| 飘雪影视在线观看免费完整| 日韩人妻中文字幕毛片A√| 色欲狠狠躁天天躁无码中文字幕| 性xxxxfreexxxxx欧美牲交| 精品无码久久久久成人AV| JYZZJYZZZ免费视频国产在线观看| 风流老熟女一区二区三区| 国产一区亚洲欧美成人| 亚洲女初尝黑人巨| 高清国产天干天干天干不卡顿| 97国产一区二区三区| 亚洲国产中文一区二区三区网站| 国产亚洲一区二区三区啪| 国产成人无码精品久久二区三区| 天堂人妻在线中文版| 高级艳妇交换俱乐部小说|