[shri_naik]

Hello everybody,

Need help in calculating the clamping tonnage of a part size 450mm length x 250mm width. Raw material = PP. Cavity 2 .Kindly help.
projected area = 450x250 = 112500 mm2.

Please help as getting confused with many different formulas on web.

Thanks.

[cadguy247]

what does the part look like? runner system and sizes? what are the wall thicknesses, gating location and type of gate? these factors will affect injection pressure, then you take the total projected area and use a "tonnage factor" based on those part/mold factors to calculate. I don't actually know if there is a formula to come up with this "tonnage factor" I just these "tonnage factors" based off of my experience and the experience of people I have worked with over the years.

Having a mold flow done always helps, but is not needed.

Another thing to take into account fatigue strength of steel in the sense that if you have too much steel preloading against each other at the parting line, this will take away from the overall clamping tonnage. but this should be taken into account during the mold design.

If you post some of the items I listed in the first line then I can give you a good reference point, until then I will look up these "tonnage factors" that have used over the years. In 24 years as a mold designer I haven't had a parting line blown open on me yet...

2-3 tons per square inch for general materials and part designs is what I use , 3-5 tons per square inch for part designs with thin wall sections.

Hope this helps

[mactec54]

Hello everybody,

Need help in calculating the clamping tonnage of a part size 450mm length x 250mm width. Raw material = PP. Cavity 2 .Kindly help.
projected area = 450x250 = 112500 mm2.

Please help as getting confused with many different formulas on web.

Thanks.

You will need a minimum of 525 ton up to 875 tons clamp to make that part

[Lucy-XM Mold]

Did you start to build this mold? Any further questions, you can mail at [email protected]