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Farkas
6th February 2013, 02:44 PM
Hi there, my question today has to do with water cooling, I don't beleive my plant has adequate water flow through there system. This one mold is capable of running 6 second cycle but has to be slowed down due to the deformation of a hot gate. I beleive we have a laminate flow and what we need going through this mold is Turbulent. I am in the process of buying some flow gauges so this is all prior to doing so, I just wanted someone else opinion. I have two gages on the molds manifolds right now .
60 PSI going IN
10 PSI going OUT

to me this doesnt seem right wouldnt you need more back pressure to cause a turbluent flow? and I feel its just coasting through causing laminate flow.

any thoughts please, i need some ammo for my arsenal.

Thanks

Farkas

ruhlj
6th February 2013, 07:26 PM
Farkas;977]Hi there, my question today has to do with water cooling, I don't beleive my plant has adequate water flow through there system. This one mold is capable of running 6 second cycle but has to be slowed down due to the deformation of a hot gate. I beleive we have a laminate flow and what we need going through this mold is Turbulent. I am in the process of buying some flow gauges so this is all prior to doing so, I just wanted someone else opinion. I have two gages on the molds manifolds right now .
60 PSI going IN
10 PSI going OUT

to me this doesnt seem right wouldnt you need more back pressure to cause a turbluent flow? and I feel its just coasting through causing laminate flow.

any thoughts please, i need some ammo for my arsenal.

Thanks

Farkas[/QUOTE]

S.Kern
6th February 2013, 07:35 PM
Do you mean to say that you have water manifold gages mounted into the manifolds themselves, and they are reading 60 psi inlet or supply, and 10psi outlet or return ? If so then you have adequate supply, in fact, excellent supply differential at 50psi. What does that Gage say when all line are open? The same delta P? Then you need the flow gages to ascertain flow rate to critical circuits. If gate deformation is the problem, and hot runner, then you may never run too much faster due to improper cooling at the gate insert, a long term problem with hot runner tools. You don't mention gate style but valve gating sometimes gives improved cycles.

ruhlj
6th February 2013, 07:37 PM
you are on the right track in getting some water flow meters to measure gpm's. One check you could do right away is to measure the supply temperature and the return temperature to the mold. If there is more than a 2 to 3 degree difference then its very possible you have lamiar flow. Your supply and return pressures look good. A high return pressure would mean there is restriction of the water returning to the tank so it could affect the amount of gpm's thru the mold.

The second area to check is build-up on the surface of the water channels in the mold. If you have more than a 1/32 of an inch this would reduce heat transfer by close to 50%.

I have seen a lot of molds with the lack of cooling around a hot gate. Not sure what type of hot runner system you have so its hard to comment on some possible solutions.