I was recently asked a specific question about water lines and wanted to re-iterate a point…
What is a Flow Meter
A flow meter is a device which you place in-line with the cooling to measure the mass flow of coolant. Many of these can be purchased as part of a machined block with additional components such as temperature and pressure gauges also attached. Typically quick-connect style fittings are attached to either side of the block so that it can be attached directly to the water lines.
How to Use a Flow Meter
If you have a cooling line suspected of having a blockage, you can attach the flow meter and measure the flow and line pressure (if available). This flow can then be compared to a different line for comparison. Always make sure you isolate the circuit to ensure the pump is providing adequate pressure to the line in question.
You can also use the flow meter to help balance flow in a parallel water-line setup. Since a higher percentage of the water will flow through the circuit(s) with the least resistance, an imbalance will result in non-uniform coolant distribution across the mold. You can measure the water flow through each circuit of the parallel configuration. This information can be used to adjust the layout to make the flow more even throughout the system.