Metering Accuracy of Liquid Filling Machines

Metering Accuracy of Liquid Filling Machines


As a filling device, the liquid quantitative filling machine mainly pours a preset amount of liquid products into packaging containers. The liquid quantitative filling machine is a kind of measuring instrument, which can effectively guarantee the interests of both manufacturers and consumers. Therefore, in order to effectively safeguard the interests of both sides, it is necessary to ensure the measurement accuracy of liquid quantitative filling machines. Generally speaking, there are many factors that affect the measurement accuracy of liquid quantitative filling machines. It is necessary to verify the liquid quantitative filling machine, to reduce the out-of-tolerance error of its measurement, and to coordinate the conveying action between the packaging container and the filling head, so as to effectively improve its measurement accuracy.
 
1. Filling Machines for Filling Foam Liquid
 
For the filling machine that fills foam liquid, the most important application object is beer. The power form of beer transportation is the backpressure in the wine tank. Generally, when the beer reaches the filling machine, it is difficult to keep the pressure stable, which leads to the overflow of carbon dioxide in beer and affects the filling effect of beer. In order to ensure the accuracy of measurement, a wine pump can be added to the pipeline, and the frequency conversion control technology can be used to maintain the stability of the pressure and ensure that it can supply wine at constant pressure, so as to meet the requirements of foam liquid filling. In addition, in actual verification, the workload tester can choose beer bottles, and when loading containers, the filling line can be used to ensure that it is 3 times that of the filling head, and it is numbered to avoid errors. After filling, it must be sealed, and the filling result can be checked by refrigeration. When adjusting the conveying pressure value, the filling result must be taken as the basis to ensure the accuracy of measurement.
 
2. Traditional Self-flow Constant Volume Filling Machines
 
General filling machines mainly fill objects, which can be divided into fully automatic filling production lines and semi-automatic filling. At present, the specifications and structures of quantitative filling machines for liquid materials are diverse. According to their quantitative principles, they can be divided into fixed-weight filling machines for quality control and fixed-volume filling machines for capacity control. For the traditional self-flow constant volume filling machine, the measurement errors are mainly reflected in two aspects: First, the measurement is caused by dripping error; Second, insufficient rehydration leads to measurement errors. For the occurrence of dripping, the leakage of the pipeline can be checked. In case of insufficient rehydration, we can increase the flow rate and flow rate of the incoming liquid, and reasonably control the height of the liquid level. In addition, the error of the measuring cup can also lead to the measurement error, so the fine adjustment system of the measuring cup can be adjusted, ensuring its consistency.
 
3. Filling Machines for Filling Hydrocarbons
 
Generally, hydrocarbons will be affected by temperature, which will lead to the change of their volume, thus reducing the measurement accuracy. The temperature control mainly includes the ambient temperature and the temperature of the filling liquid. In actual verification, the filling quantity must be effectively calculated in combination with the public notice V = VX (1-BT). The volume of liquid at current temperature is expressed by V. The standard volume of the substance at 20℃ is expressed by Vx. The expansion coefficient of liquid is expressed by B, and the difference between the current temperature and standard temperature is expressed by T. Generally, when verifying, the temperature difference of the filling medium is controlled at about 5℃. Combined with the verification results, the optimal temperature of the environment and the filling liquid can be effectively determined, so as to ensure the scientificity and accuracy of the measurement.
 
4. High Accuracy Volumetric Automatic Filling Machines
 
Generally, at the end of filling, overflow may occur, which leads to the decrease of measurement accuracy. In order to effectively improve the accuracy of measurement, it is necessary to reasonably select the filling speed and effectively improve the filling speed. At the same time, during filling, the speed change form of "first fast and then slow" is adopted to change the operating frequency of the stepping motor to ensure the accuracy of measurement. Generally speaking, in the process of processing the metering pump, there will be some errors, which will lead to the filling amount in the filling head.

The measurement error is inconsistent. So in the actual operation process, the total step number of the stepping motor can be manually adjusted. In addition, the temperature of filling liquid will also affect the accuracy of measurement to a certain extent. When the temperature increases, the volume of liquid increases. When the temperature decreases, the liquid volume decreases, which often leads to errors in filling measurement. Therefore, when the equipment is running, the temperature detection system and the automatic temperature error correction system can be effectively set, and the running steps of the stepping motor can be automatically corrected in combination with the actual temperature of the liquid material, thus effectively reducing the measurement error. At present, with the development of flowmeter technology, the effective introduction of mass flowmeters in the measurement of high-accuracy filling machines can ensure the accuracy and rationality of measurement.
 
5. Cylinder Piston Filling Machines
 
For cylinder piston filling machines, because the inner diameter of each cylinder is different, there will be errors in its size, which will reduce the accuracy of measurement. At the same time, the liquid will exert pressure on the clapboard, which will lead to its deformation, resulting in measurement errors. In addition, when filling liquid with high viscosity, it is easy to inhale air, thus reducing the accuracy and rationality of measurement. Generally, when the measurement is inaccurate due to the filling machine's own situation, it is often difficult to adjust. But for the diaphragm to change shape, you can use calipers to measure the distance between each partition of the filling machine and correct it. At the same time, for high viscosity liquid, the filling speed can be reduced appropriately.
 
6. Liquid Level Positioning Filling Machines
 
For the liquid level positioning filling machine, the measurement standard mainly depends on the liquid level. The liquid level positioning will be influenced by the quality of the detection device, the closing speed and stability of the filling valve, which will lead to measurement errors. In order to reduce the error, an effective liquid level detection device can be introduced. Based on its required height, once the liquid level reaches the corresponding height, a stop signal should be sent in time to effectively control and close the filling valve. At the same time, on the premise of meeting relevant requirements, control the filling speed at a low level to ensure the accuracy of measurement.
 
Conclusion
 
Liquid quantitative filling machines are widely used in food, medicine, chemical industry and other industries, and their measurement accuracy is directly related to the accuracy of filling products, so it is necessary to establish the measurement standard of filling machine standard device. Generally speaking, ensuring the measurement accuracy of liquid quantitative filling machines can effectively reduce the losses of enterprises and increase the economic benefits of enterprises. Therefore, in the actual production process of products, we must constantly innovate technology, starting from the details, in order to improve the rationality and accuracy of their measurement. Ensure that it can better serve the development of enterprises and promote the sustainable development of enterprises.