高清国产午夜精品久久久久久_超级碰在线_一本一道中文字幕_亚洲国产中文字幕_日韩欧美激情_国产精品久久久久久久久久久久

current location: Home   >> News >> Industry trends

Pneumatic butterfly valve installation requirements and matters needing attention

Installation requirements of pneumatic butterfly valve:

1, the installation of pneumatic butterfly valve to pay attention to the direction of media fluid and arrow

2, pneumatic butterfly valve open stem valve can not be geographical device, to prevent stem corrosion, there is a cover in the trench, the valve should be installed and maintenance and inspection and operation

3, pneumatic butterfly valve in the horizontal pipeline installation, the valve stem to vertical upward, or tilt a certain Angle, the valve stem is not allowed to be installed down

4, flange and thread connection of the valve, the valve should be closed during the installation. Install flanged valves to ensure that both ends of the flanges are parallel and concentric.

Matters needing attention:

1, the relationship between the opening of the pneumatic butterfly valve and the flow rate, basically changes in a linear proportion. If used to control the flow, its flow characteristics and piping flow resistance is also closely related, such as the two pipelines installed valve caliber, form, etc. are all the same, and the pipeline loss coefficient is different, the valve flow difference will be very big.

2. If the valve is in a state with a large throttling range, cavitation is likely to occur on the back side of the valve plate and the valve may be damaged. Generally, the valve is used outside 15°.

3, pneumatic butterfly valve in the opening, the valve body and disc front of mouth shape to valve shaft as the center, on both sides of the form a complete different state, the butterfly plate on one side of the front end of downstream water direction, the other side of the upstream water direction, therefore, on one side of the valve body and valve plate form like opening nozzle shape, on the other side is similar to throttle aperture openings, nozzle side of more quickly than the throttling lateral velocity, and the side of the throttle valve will produce negative pressure, under the rubber seals often can appear fall off.

4, pneumatic butterfly valve operating torque, due to the opening and valve opening and closing direction of different values, horizontal pneumatic butterfly valve, especially large diameter valve, due to water depth, valve shaft, launching head difference produced by the torque can not be ignored. In addition, valve inlet side device elbow, the formation of deflection, torque will increase. When valve is in middle opening


主站蜘蛛池模板: 国产精品第十页 | 欧美视频在线观看 | 中文一级片 | 国产男女视频在线观看 | 九九全国免费视频 | 天天看天天干天天操 | 99在线精品视频在线观看 | 欧美日韩国产一区二区三区播放 | 日本在线视频二区 | www.av视频在线| 黄 色 成 年人在线 黄 色 大 片 网站 | 欧美亚洲国产精品久久 | 日本六九视频 | 黄网址在线观看 | 人人爱天天做夜夜爽2020麻豆 | 国产人成精品午夜在线观看 | 久久99精品久久久久久秒播 | 精品欧美一区二区在线观看 | 欧美亚洲国产一区 | 蜜桃tv永久网站 | 久久桃花网 | 热久久这里只有精品 | 久国产视频 | 欧美大全 | 久久久久久久99精品免费观看 | 久久精品店 | 欧美亚洲国产精品久久高清 | 欧美午夜视频一区二区三区 | 天天av天天翘天天综合网 | 久久99热精品| 久久精品日本免费线 | 精品久久免费观看 | 天堂在线观看视频观看www | 男女污污黄无遮挡免费 | 国产精品高清视亚洲一区二区 | 亚洲午夜精品一区二区 | 日本精品一区二区在线播放 | 日本免费福利视频 | 国产做a爰片久久毛片a | 天堂在线www网亚洲 天堂在线观看视频观看www | 蜜臀导航|