What information is needed to properly select a metering pump? 1. Is the measurement of liquid flow. 2. Measured the main characteristics of the liquid, such as chemical corrosion, viscosity and specific gravity. System back pressure. 4 suitable suction height. 5. Other options required, such as analog control, pulse control, flow monitoring and timer. What are the main advantages of electromagnetic driven metering pump? Electromagnetically driven metering pumps have only one moving part - the armature shaft. Generally, the less moving parts, the more reliable the metering pump works. Metering pump is ideal for low-flow, low-pressure workplaces, and good compensation in the supply voltage fluctuations. And fixed frequency, change the stroke length of the metering pump, the fixed stroke length, change the frequency of the metering pump What are the advantages? By calibration, the dosing amount for each stroke is known. The total dosage can therefore be calculated (dosing = dosing per stroke * frequency). The total dosage is linear with frequency (50% frequency = 50% dosing). Through external pulse or analog control, dosage can be transferred from minimum to maximum in one second. In addition, it is much less costly than motor-driven stroke length adjustment. How to use the performance curve of the metering pump? 1. Find the performance curve corresponding to the selected metering pump. 2. Indicate the current back pressure in the chart below. 3. Determine the correction factor, taking the backpressure value in bar, up to the curve, and read the correction factor vertically left at the intersection. 4. Divide the required dosage value by the correction factor to give the value in ml / min. Or L / h. Put the calculation result in the middle of the dosage scale. 6. When placing this value on the dosing scale, use a ruler to find the stroke length setting and stroke frequency setting.