Are there any blow molding simulations or wall thickness prediction software packages?

There are various types of blow molding simulation software on the market. Because this software is so specialist it is usually quite expensive. Software to predict wall thickness change as a result of the parison stretching to the contours of the mold: Have a look at the site: https://www.t-sim.com/www/index.html. You can download the full working version, but only run their example files.

Polymer Training Ltd. Offer software to simulate the effect of process changes have a look at their site: https://www.polymertraining.co.uk/home.htm The software is called Picat.