Grundfos Dosing Pump DDA 120-7 FCM-SS/T/SS-F-31A3A3BG

 

 

A dosing pump is classed as a positive displacement pump and is designed to inject a highly precise quantity of substance into an existing flowing fluid.

 

An application example of a dosing pump is the treatment of drinking water with added chlorine to kill bacteria.

 

 

 

 

 

The Grundfos DDA unit is a motor driven diaphragm (or membrane) dosing pump.

 

 

 

The pump action is generated by the reciprocation of a PTFE membrane acting against a fluid and controlled by valves.

 

 

 

The referenced model weighs 16lb and has a maximum sound pressure level of 80 dB(A).

 

 

 

 

 

 

 

Mechanical data highlighting capacities, pressures and stroke information.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

From the above data the maximum operating pressure (MOP) is stated as 101 psi (7 Bar).

The maximum allowable working pressure (MAWP) is defined as the highest permissible pressure a system can accommodate at a certain temperature at its weakest point. This value is slightly higher than the maximum operating pressure (MOP).

Image below shows a typical DDA model cross sectional view.

 

 

 

 

The pump manufacturer provides comprehensive technical literature for this pump which includes recommendations for installation.

• An inlet line filter will protect pump from debris ingress.
• A pressure relief valve on the outlet line will safeguard the system against excessive pressure.
• Under certain operating conditions a pulsation damper should be installed.