Hello Amlaan Dasgupta ,

Contracting anyone of them will create issue in both the cases.

You can use a metal shaft as core and insert it into soften plastic so that it fit onto a metal shaft. In short you will need an external source for doing this activity.

Get some dry ice and hold it against the shaft to shrink the metal shaft. This might reduce the diameter enough that that the PP will slide on. You may want to use a heat gun to soften the PP at the same time.

Dear Amlaan,

Please consider that we do not have all experimental information for the best suggestions. You would like to “expand” (NB: to increase) the diameter of a PP item/part to fit on a metal shift. What about the number of pieces and the differences in diameter (actual vs. desired)?

Because the PP parts can be easy shaped by mechanically machining (drilling, milling, shaping, etc.), I guess that this could be a facile way allowing to solve your problem (NB: eventually you need the advice of a mechanical specialist !).

Good luck and best regards,

Marius

PS: see you, https://www.ineos.com/globalassets/ineos-group/businesses/ineos-olefins-and-polymers-usa/products/technical-information--patents/ineos_polypropylene_processing_guide.pdf

https://www.pentaprecision.co.uk/material-resources/plastic-resources/polypropylene-machining

https://www.millerplastics.com/polypropylene-machining/

Marius Murariu the no of pieces are around 2000 pieces in 6 hours. Currently for this water bath is being used wherein the impeller is heated upto 80 degrees. However due to this we get unwanted rust of a different device. Hence I am looking for an alternative method.