CARX compound exhaust valve body is round barrel. The valve includes stainless steel float, lever and disc. This valve is installed in the pump discharge or water distribution pipeline, set is used to eliminate the air in the tube, to improve the efficiency of the use of the pipeline and water pump, when once produced negative pressure tube, this rapid inhalation outside air valve, in order to prevent the pipeline damage due to negative pressure. When the water in the tube begins to fill. The disc is in the open position and carries out a lot of exhaust when the air is finished. The valve is filled with water, the float is rising and the disc is closed and the exhaust is stopped. When the water in the tube is normally transported, if a small amount of air is gathered in the valve to a considerable degree, the water level in the valve drops, and the air is expelled from less than L. When the water pump stops, the water in the pipe is empty or the inside of the tube produces negative pressure. At this time, the plug head is opened quickly, and the air is inhaled to ensure the safety of the pipeline. Medium temperature: 0 ~ 80 ℃.