PU MP R EFER ENC ES How to Calculate the Pressure Requirement of Your Experiment T 4 5 6 7 PUMP REFERENCES How to Calculate the Pressure Requirement of Your Experiment 110 he following chart will help you determine the pressure requirement of your experiment. This is important in selecting the correct pump with the proper psi capability for your application. Choose the selections that are the closest to your experimental conditions or write in your actual values. Once you have filled in the chart call us for technical assistance if needed. 1 Nature of the sample you are flowing into (Application) 2 The flow rate of the material 3 The surface area of the syringe and the linear force capability of the pump The tubing diameter The tubing length Viscosity of the material being pumped The temperature of the material being pumped NORMAL PRESSURE 0 to 30 psi (0 to 2 bar) HIGH FORCE 31 to 150 psi (2.1 to 10.2 bar) EXTREME HIGH PRESSURE 151 to 2000 psi (10.3 to 137 bar) 1. Application L O W H I G H Flow into open containers, i.e. titrations, food trays filling Inject into Tissue, i.e. Drug infusion into muscle, brain Flow into closed container, i.e. Reaction Chamber 350 to 400 psi High viscosity solutions at high flow rates in a short period of time, i.e. Corn syrup 2. FLOW RATE - Pumping Speed (The faster the flow rate, the higher the pressure) 0.003 µl/hr to 140 ml/min 141 ml/min to 220 ml/min 3. SYRINGE SIZE (Syringe volume/plunger area + linear force of pump) 10 µl to 1 ml ie. 500 µl/min x 20 lbs = 1500 psi 4. TUBING SIZE (Inner diameter, Smaller ID = higher pressure) SMALL - Capillary (the longer more pressure) LARGE - Hose 5. TUBING LENGTH - DISTANCE (Depends on ID Smaller ID = higher pressure) Short, < 1M Long, > 1M 6. VISCOSITY OF MATERIAL TO BE PUMPED (Higher viscosity = higher pressure) AIR WATER OLIVE OIL PANCAKE SYRUP HONEY PEANUT BUTTER 18°C = 0.0182 cP 20°C = 1.002 cP 20°C = 84 cP 20°C = 2500 cP 20°C = 10000 cP 20°C = 250000 cP 7. TEMPERATURE OF SOLUTIONS BEING PUMPED (Higher temperature = lower viscosity = lower pressure) 0 to 15°C 15 to 80°C Harvard Apparatus phone 508.893.8999 toll free U.S. 800.272.2775 fax 508.429.5732 www.harvardapparatus.com