Caching Active Storage in the Browser

I am been using Carrier wave to up load images. I upload them then have the ability to create.a cropped version which I show on my web site.

The cache nicely on the web pages so they don't need re downloading every time they are shown.

I can seem to do this with Active Storage as the link is different on every page refresh is this just the way it is at the moment.

Also every time I crop It creates a new version instead of replacing the old cropped version as in Carrier wave.

I have not found any solutions in google yet.