digital Waist wheel flow meter/ oval gear Volume type flowmeter

 When the measured fluid flows through metering chamber, form pressure difference in the inlet and outlet of the meter, waist wheel rotating under this pressure difference. At the same time, through a pair of drive gear fixed on the waist wheel axle, to make the two waist wheels maintain continuous rotation. With the rotation of the waist wheel wheel, fluid via metering chamber is continuously discharged from the meter. The amount of fluid flowing through each is four times the volume of the metering chamber, by sealing couplings and reduction mechanism, slow down the rotation then pass to frequency counter, frequency counter indicates the instantaneous flow and cumulative flow of the fluid .
Install the sender in the counter mechanism, it become waist wheel flowmeter with the sender . With display instrument or computer systems support, it can achieve remote (quantitative, cumulative, instantaneous, and other functions) automated measurement and control.

4.4.1 Flow meter installation
When install the flow meter, no direct welding in the import and export flange, so as not to burn the internal parts of the flow meter.
Before installing the flow meter, the newly installed or repaired pipeline must be cleaned to remove the debris.
The flow meter shall be installed in the place of easy maintenance, no strong electromagnetic field interference, no strong mechanical vibration and thermal radiation effect.
The flow meter should not be used in the occasions where the flow is frequently interrupted and there is a strong pulsation flow or pressure pulsation;
When install the flow meter outdoor, there should be an upper cover to prevent the penetration of rain and sun exposure that affect the service life of the flow meter.
 The flow meter can be installed in any angle, and the flow direction of the fluid should in accordance with the direction indicated on the flow meter. 
 In pipeline construction, should consider the installation of telescopic pipe or bellows, so as not to cause serious stretch or break to the flow meter. 
 The flow meter should be installed with the pipeline coaxially, and prevent sealing strip and grease enter the pipe cavity. 
 When use the external power supply, the flow meter must be reliable grounding. Do not use the earth wire with heavy current system jointly. In the period of pipe installation or maintenance, do not lap the earth wire of welding system with the flow meter. 
 In order not to affect the normal flow of fluid and easy maintenance, install bypass pipe according to the indication of figure 4. And ensure the front of the straight pipe section ≥3DN, the back of the straight pipe section ≥1DN.

4.4.2 The use and replacement of the built-in battery
battery electric power display
When the battery display the power has only one grid, the user should replace the battery within one month; when it only display the shape symbol of the battery, the battery power is depleted, and the battery must be replaced immediately. 
Battery replacement method
Open the back cover of the intelligent flow totalizer, loosen the three screws on the battery cover plate, unplug the battery socket, take out the battery, and reinstall after replace the battery with a new one.