欧美资源I你懂得福利影院I久久国产热Iwww夜夜操comI国产精品二区在线I国产视频91在线I国产精品专区在线I手机在线观看国产精品I成人黄色中文字幕I免费在线观看av网站I国产一级片网站I欧美zooxxxI成人av网站在线观看I黄色片片片I亚洲a成人vI99精品热Iwww.狠狠插.comI亚洲精品国产精品国

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.