Precision metering pump in use process need to pay attention to the problem, basically be to see what kind of precision, dosing pump manufacturer tell you yu machinery including steady-state accuracy, linear accuracy and repeat precision.

1) steady precision of mechanical diaphragm metering pump: rated flow rate of plus or minus 2%. If the measured pump measured 100% of the stroke flow is 1000L/h, the steady state precision allowable deviation is plus or minus 2%*1000= plus or minus 20 L/h. Steady state precision is the flow deviation of the pump and the related system at different time points to calibrate the pump flow without any adjustment and change.

2) linear precision: the rated flow rate of plus or minus 3%, if the measured pump measured 100% of the stroke flow is 1000L/h, the linear precision allowable deviation is plus or minus 3%*1000= plus or minus 30L/h. Linear precision refers to the deviation between the measured flow rate and the optimal fitting value in the range of 10%~100% range of the metering pump

3) repeat accuracy: the rated flow rate of plus or minus 3%, if the measured pump measured 100% of the stroke flow is 1000L/h, the repeat accuracy allowable deviation is plus or minus 3%*1000= plus or minus 30L/h. Repeatability refers to the metering pump within the range of 10% ~ 100%, choose a trip point for flow calibration, and change the stroke of the pump to run after a period of time, once again return to the original schedule point for flow calibration, the resulting flow deviation.