Use of unloading flow meter and adjustment of operating conditions

1. In a piping system with a flow meter, it is necessary to avoid generating or entering air, otherwise it will cause inaccurate metering. Therefore, the flowmeter should be used when the entire system is full of oil.

2. The flow meter system precision instrument, the measurement room interior detection element gap is very small. Therefore, large particles and other impurities must not enter the flowmeter. It is forbidden to use the flowmeter without a filter.

3. The unloading flowmeter should avoid working under pressure fluctuations and overload impact. Therefore, it is necessary to switch the fuel ball valve and the fuel gun (connector) smoothly and slowly during use, and prevent the measured medium from flowing backward into the flowmeter.

4. When the flow meter is installed, the shaft of the waist wheel should be installed horizontally. The direction of flow through the flow meter should be consistent with the direction indicated by the arrow on the housing; the flow meter should not be subjected to expansion, contraction, deformation, and vibration of the pipe.

5. The flowmeter shall not exceed the specified flow rate and pressure range. In continuous operation, the flow in the pipeline shall not exceed (600-800) L/min, and the maximum flow rate shall be specified in order to accommodate the sudden increase in flow rate. , only for short or momentary use.

6. The head of the unloading flowmeter has a zero-return knob. Before the work, it should check whether the count and the pointer are back to zero. After each refueling operation, turn the knob clockwise to return the hands and one count to zero. It is forbidden to move the pointer when the flowmeter is working.

Condition adjustment of the unloading flow meter is mainly required to stabilize the flow state and prevent vaporization. Among them, the flow state stability includes the stability of the flow rate and the stability of the flow state. They have certain links with each other. In order to maintain the stability of the flow, it is usually solved by setting a certain length of straight pipe section or rectifier and constant current valve before and after the flowmeter. There are two main reasons for the vaporization of the oil in the piping system. Because the piping is not tightly sealed, it enters into the air and piping system because the pressure is lower than the vapor pressure generated by the saturated vapor pressure. In addition, the liquid will also precipitate a certain amount during the flow. gas. Unsteady flow conditions or the presence of gas in the fluid will affect the metering accuracy of the tank car flow meter. Preventing vaporization can be achieved by installing an air eliminator and maintaining sufficient pressure before the inlet of the flowmeter.