The mass flow meters used for loading gasoline and diesel at the company, as well as the weights measured by the scale, show large differences

1. Verify the scale: based on the verification results provided by the quality supervision agency, it can be determined whether the scale is accurate； 2. Verify the quality mass flow meter to check whether there are any issues with its parameter settings; measurement errors are usually caused by short-term or continuous fluctuations in the mass flow meter or in the pipeline

With a scale, what’s the need for mass flow measurement? ... I suggest taking it apart and repurposing it. :':lol

When loading diesel and gasoline, there is a significant discrepancy between the data from the flow meter and that from the scale. When 1,000 liters of fuel are delivered repeatedly, what is the error between the readings from the flow meter and those from the scale? Is the flow meter accurate? Is the scale accurate? Do the pipes of the loading system have degassing filters and digitally controlled valves?

Is the density setting of the mass flow meter correct? It’s possible that when it was installed, power was applied directly without any parameters being set, and the system was put into use right away with no further attention given to it

Based on experience, deviations of 200 KG have also been observed in the weighing process and the amount of material loaded, with a total loading volume of 20 tons. The main reasons for such large deviations are as follows: 1. Weighing scales: Modern weighing scales have high precision, around 20 KG per 100 T. It is necessary to carry out regular calibration; for scales used in trade transactions, calibration is mandatory and should be done every six months, which helps to minimize deviations； 2. During the weighing process, the distance between the scale and the vehicle loading area is considerable; a dedicated person is needed to accompany the vehicle when it is weighed, whether it is empty or loaded, especially since the scale is located outside the factory premises ； 3. Corresponding settings of mass flow rate and pulse count between the mass flow meter and the batch controller, as well as the calibration of the mass flow meter ； 4. During the loading process, for liquids that are prone to vaporization, there may be a two-phase gas-liquid mixture or a situation where the pipe is not completely filled at first, which can lead to measurement errors by the mass flow meter; it is therefore advisable to check whether the density reading remains stable at the beginning of loading. Option four is the most likely to work; it is recommended that the controller be used solely to regulate the amount of material loaded, in order to prevent overfilling, with the data from the weighing scale serving as the basis for measurement and handover.

The mass flow meter needs to be used together with the batch controller for loading; it really can’t be disassembled.

It is possible to examine the distribution of the deviations. If all deviations are negative or positive, you can adjust parameters such as pulse equivalent, valve closure lead time, and flow coefficient. If the deviations follow a normal distribution, it may be necessary to check the accuracy of the flow meter; if its accuracy level meets the requirements, you should then consider whether the operating conditions satisfy the flow meter’s operational requirements

This post was last edited by Swimming_Fish_RHTD on 2018-12-4 at 11:07. It is recommended to consider the issue of air buoyancy correction; when calibrating flow meters, the density should be the density in a vacuum

Storage tanks with a liquid level can assist in identifying problems