For optimum life and performance, pumps should be specified so that daily operation parameters will fall in the middle of the pump performance curve. Wilden publishes multiple performance curves for most metal and plastic pump models. These performance curves are unique due to the different stroke lengths of the diaphragm assemblies. The four classifications for most are: 1) Rubber-fitted pumps; 2) Ultra-Flex™-fitted pumps; 3) Thermoplastic (TPE)-fitted pumps; and 4) Teflon®-fitted pumps. These curves are included in the Engineering, Operation, and Maintenance manuals (EOMs) for proper specification. For more information on how to read a curve Please contact us.
How to read a Wilden performance curve
Determine the flow rate your application requires and calculate the Total Discharge Head. Plot the intersection of the discharge head on the vertical axis to the flow rate on the horizontal axis. Now the air supply pressure and air supply volume can be extracted from the curve. Simply locate the line closest to this intersection and follow it to the vertical axis to the left. This is the air supply pressure needed to provide the flow rate you require at the given discharge head. Next locate the red line closest to the intersection and follow it up to where the numbers are provided. These numbers indicate the air supply volume needed to provide the flow rate you require at the given discharge head.
To pump 394 lpm (104 gpm) against a discharge pressure head of 1.4 bar (20 psig) requires 4.1 bar (60 psig) and 102 Nm3/hr (60 scfm) air consumption. Dot on chart represents the plotted intersection and the circled numbers are the air pressure and volume figures.
Temperature limitations are based on mechanical stress only. Certain chemicals will significantly reduce the maximum safe operating temperatures. Consult Wilden's chemical resistance guide for chemical compatibility and temperature limits for specific fluids.
Suction Lift Capability
The suction lift figure listed on each of the following spec pages is the maximum that the specified pump model can achieve. A complete suction lift curve that represents all diaphragm configurations is included in the EOM manuals. Suction lift values are calibrated for pumps operating at 305 m (1,000 feet) above sea level. .