How to Improve the Feeding Accuracy of Loss-in-weight Scale?
Loss-in-weight scale is an automatic weighing equipment that achieves high-precision continuous and uniform metering and feeding through dynamic continuous weighing. It can reliably, accurately and stably meter and feed various solid materials in powder, granule, flake form and various liquid materials at room temperature or requiring heat preservation, reducing material waste and improving the consistency of the mixture.
1. What matters should be paid attention to in the installation of loss-in-weight scale to improve the accuracy of feeding
1) The weighing platform must be firm
The sensor is an elastic deformation element, and external vibration will interfere with it. The impact of environmental vibration should be avoided during the use of loss-in-weight scale.
2) There should be no air flow in the environment
Because the sensor selected to improve the accuracy of weighing is very sensitive, any disturbance will interfere with the sensor.
3) The shorter the connection distance, the better
The shorter the connection distance between the large silo and the upper hopper, the better, especially for those materials with strong adhesion.
When the connection distance between the large silo and the upper hopper is longer. The more materials adhere to the pipe wall, when the material on the pipe wall adheres to a certain degree, once it falls, it will be a very big disturbance to the loss-in-weight scale.
4) Minimize the connection with the outside world
Minimize the connection with the outside world. Any external weight acting on the scale body must be kept constant in order to reduce the influence of external forces on the scale body.
2. How to improve the accuracy of loss-in-weight scale replenishment?
1) The feeding speed should be fast
The feeding speed must be fast, so we must ensure the smoothness of the feeding during the feeding process.
For materials with poor fluidity, in order to prevent them from bridging, the best solution is to add mechanical agitation in a large silo. The biggest taboo is air flow to break the arch. But the mixing cannot be running all the time. The most ideal thing is to keep the mixing process consistent with the feeding process, that is, to keep in sync with the feeding valve.
2) The upper and lower limits should be set appropriately
The lower limit value of the replenishment and the upper limit value of the replenishment should be set appropriately so that the bulk density of the material in the hopper is basically the same between the two quantities.
This can be obtained by observing the frequency change of the frequency converter. When the bulk density of the materials in the hopper is basically the same, the frequency of the frequency converter basically does not change much.
Setting the lower limit value and upper limit value of the replenishment properly can improve the control accuracy in the replenishment process. Because it has been mentioned before that the loss-in-weight scale is under static control during the replenishment process, if the frequency of the inverter before and after the replenishment can be kept basically unchanged, the measurement accuracy of the replenishment process is basically guaranteed.
In addition, under the condition that the bulk density is basically the same, try to reduce the number of refills, that is, try to refill more materials each time. The two contradict each other and must be considered in an overall manner. This is also the key to ensuring the accuracy in the replenishment process.
3) The replenishment delay time should be set appropriately
The replenishment delay time should be set appropriately, make sure that all materials have fallen on the scale body, and the shorter the setting time, the better.
During the debugging period, you can set the delay time longer, and observe how long the total weight on the scale body can stabilize without fluctuation (not becoming larger) after each replenishment (the total weight on the scale body decreases steadily). Then this time is the appropriate feed delay.