高清国产一区二区三区在线-国产在线精品一区二区夜色-亚洲人成77777在线播放网站-亚洲精品久久久久久中文-无码 人妻 在线 视频

1. Sandwich-type butterfly valve is simple and compact in structure, light in weight and convenient for installation, disassembly and maintenance.
2. Operating torque is small, turn 90° and open and close lightly and quickly.
3, small flow resistance, flow characteristics approximate inclined straight line, good energy saving effect.
4. Butterfly valve has reliable sealing, zero leakage and long service life.
5, can be made of all kinds of materials, suitable for all kinds of media.
6. Flow characteristics tend to be straight line with good regulation performance.
7, butterfly valve opening and closing test times up to tens of thousands of times, long life.