Mold surface temperature

[ErcanGuler4332]

I have got a problem.
We made the analysis of the bumper mold that is being used on the injection machine with the same parameters with the machine. The mold flow analyse results are different then the real values. The real temperature of the mold surface is around 60-70°C however the calculated temperature is around 35-40°C. We would like to learn does moldflow take in to account the manifold temperature during calculation of the mold temperature?
I want to learn valve gate temperature to effect mold surface temperature?

Thank you
Mehtap ÖZ

[AnaMariaMarin]

Hello,

Yes, you do need to set up the temperature of the water in the "Inlet" boundary condition. Also make sure you are using the correct mold material and if you have any inserts those should have the property of the correct material set.

Hope it helps,

Ana Maria Marin
Moldflow certified. Independent instructor.

[dkosheba1]

Yes, the hot runner or Manifolds have a significant heat loss into mold. I often find that analysis shows the stationary mold half should be cooler than the core or moving half, only to find the cover running hotter due to hot runner clearances. Check properties of the 1d beams, the heat loss into mold option, change it from constant flux to insulating properties, and then edit the air gap and transfer rate into tool. For starters I would double the default values, or use the help menu to determine the default values and double them. You will then find more heat going into tool.

My other thought is to collect your actual water temperature in and out of mold with flow rate. You may not be matching this aspect in analysis.

Don

[ErcanGuler4332]

Hello Ana Maria,
Thank you very much for your answer and time.

We always used mold material 1,2738. The tool material we usually use in moldflow is P20.Is it correct ?

Best Regards

Mehtap ÖZ

[AnaMariaMarin]

Hi,

Besides what Mr. Kosheba recommended, I would suggest you to review and edit (if required) the properties of the material mold.

It is a known fact that there is a large difference in the properties of commercial grades of available P20, this was published in an ANTEC paper several years ago and it is listed in the training manuals. The difference I am referring to are thermal conductivity which will affect significantly the results of the cooling analysis.

From a quick search on internet I found that the mold material you are using (1, 2738) seems to be listed as P20+Ni, http://www.imould.com/products/Stamping+Die+Moulds/judyyf/Mould+steel+(P20%2BNi/718/DIN1.2738)-18229.html

So, you could review your mold material properties sheet and adjust as necessary.

Regards,
Ana Maria