Recently one of our customers gave us a challenge.
The challenge: Mix water and detergent at a 1 to 25 ratio and deliver 250 ml/min. The current setup was using scales to measure each liquid which then had to be pumped into the application.
Goal: Remove the scales, mix the fluids and pump it into the application.
Looking at the specification we came to the conclusion to use two pumps, which individually could be adjusted to reach the desired ratio. The first step was to find a suitable pump for each liquid. We used two of our SP1-OEM pumps, one with a 4mm ID tube and one with a 0,8mm ID tube. Running each at 30 RPM would deliver 1 ml/min respectively 25 ml/min hence the preferred ratio.
Running the pump on left hand side CCW and the pump on right hand side CW simplifies routing of the tubes. A T-connector connects the low ratio flow to the outlet of the high ratio flow. Not only does this solution solve the problem, but once the two liquids join together in the single outlet tube, they blend together perfectly and there is no need to steer them together.