Actually there is a solution. If you try and pull the tubes out it wont work as its friction fit. However if you move them from side to side a little, keep wobbling and they will eventually loosen. This will work unless the tubes/pipes have been bent from trying to prise them apart. Once they are free apply furniture polish around the rings so that in the future sticking metal pipes will not stick together so much.
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Actually there is a solution.
If you try and pull the tubes out it wont work as its friction fit. However if you move them from side to side a little, keep wobbling and they will eventually loosen. This will work unless the tubes/pipes have been bent from trying to prise them apart. Once they are free apply furniture polish around the rings so that in the future sticking metal pipes will not stick together so much.
No easy solution. try heating tube in hot water and then brute force