Design guidelines for blow molded part

[borny27]

The project I'm currently working on will involve the design of a pneumatic accumulator for the blow molding process. It's roughly the size of a 16oz soda bottle, but with much simpler geometry.

My immediate question is what are the maximum wall thickness limits for the process, given the size I'm looking at?

Additionally, any suggestions for sites or books with good info on design guidelines for the design engineer? Something with some meat, not just generalized text like "use generous radii".

Thanks.

 

[SVO1969]

Generally, you can make the wall thickness up to your own imagination. Consider that there are pool supply companies that make their sand-filter units up to .500" thick. Things also to consider are:

1. The cycle time necessary to cool the part according to it's wall thickness. Of course this may become a cost issue.

2. Design of the water cooling system within the mold in order to provide turbulent flow.

3. Proper water supply to the machine in order to achieve turbulent flow. Generally speaking the supply water pressure should be no less than 70 psi and the flow rate of 60 GPM minimum. If you can achieve more, the better.

4. Necessary wall thickness to accomodate the hoop stress involved with making such a part.

5. Understanding of ASTM D-629. Considering the situation and the end use involved, this would seem to apply to the product.