It's the cooling Stupid! #3

Larger manifolds and no looping is the first step to proper cooling.  The problems come with natural restrictions like bubblers.  If you have a sixteen-cavity mold where all the cores have bubblers they are usually hooked in series with four rows of four with an Inlet on one sit and Outlet on the other. With only a little thought you can see the resistance of the first bubbler is past to the second and so on.  Dumb.  A more efficient way to service bubblers is with a parallel watering system.  Construct you mold so that each bubbler has its own inlet and it dumps to a common outlet.  This is done with an internal manifold system.

But even with servicing each cavity separately you must have TURBULENT flow to make it work.  Slow moving water is LAMINAR – this is like a smooth stream:  The water on the top flows but there is little movement on the bottom.  Turbulent flow is where the water actually tumbles.

You can purchase flow meters from several sources.  What you need is a minimum flow to obtain turbulent flow.  Here's a table to use:
 

The general rule of thumb is 1.25 GPM through any circuit will guarantee turbulent flow.  A look at the chart will explain this Rule of Thumb.  If you can't make the minimum flow, put a booster pump on your inlet circuits.  I had one client that actually had 120PSI on his inlet lines!  A bit much but it saved him 8% on his cycle times.

Do the math. Keep the profits.

Call with questions
Bill Tobin – President WJT Associates
wjtassociates.com
303 604 9592