www.久久爱.com_狠狠婷婷_91视频在_中文字幕无码免费久久_99福利影院_美女黄网站18禁免费看胸罩

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.