Open channel flow meter, the larger the flow in the channel, the higher the liquid level in the weir; the smaller the flow, the lower the liquid level. In general channels, there is no definite corresponding relationship between liquid level and flow. Because of the same water depth, the size of the flow is also related to the cross-sectional area, slope, and roughness of the channel. When installing slot weirs in the channel, the gap of the weir or the narrowing of the slot is smaller than the cross-sectional area of the channel. Therefore, the corresponding relationship between the upstream water level of the channel and the flow rate mainly depends on the geometric size of the channel and weir. The same trough and weir are placed on different channels, and the same liquid level corresponds to the same flow rate. The slot weir converts the flow into a liquid level. The flow meter of the Babbitt channel open channel is composed of three parts: a flow totalizer, a liquid level gauge and a Babbitt channel weir.

Gas ultrasonic flow meter is an ideal solution for accurately measuring high-pressure gas. Compared with traditional measurement methods, especially when measuring large diameters, it greatly reduces the cost. At the same time, the meter has a wide range ratio and can measure very low flow rates.