呦呦福利网I四虎影视永久免费在线观看I婷婷丁香自拍I国产精品久久久久久久久久久久久久久久I亚洲免费av网站I精品中文字幕在线播放I久草在线视频首页I爱搞搞就爱搞搞I9.1免费网站在线观看I男人的天堂操三I吉泽友贵番号I91精品成人I97成人网站I中出中文字幕

GFD/FQ multi-function fire-retardant breathing valve produced and sold by Baigang Valve Group is a ventilation device installed on the top of a fixed storage tank.Reduce the evaporation loss of oil and other liquids, control the tank pressure, to prevent the tank from being damaged by overpressure or vacuum.GFD/FQ multi-function fire-retardant breathing valve can also prevent the external flame from entering the role.GFD/FQ multi-function fire-retardant breathing valve is suitable for oil, petrochemical materials and other media, also suitable for cold areas, breathing valve operating pressure before leaving the factory are strictly tested and tested, users are not allowed to change or change the weight of the valve disc.Type of single breath valve, single suction valve, breathing valve, all kinds of structure can be combined with the flame arrestor structure, can also prepare the required nozzles.