If you've ever tried to take apart an office chair to return it, move, or simply carry it out to the trash, you know how the lift cylinder seems to be fused with the chair base & the support under the seat. When you assemble an office or desk chair, the lift cylinder, which supports the seat as well as allowing height adjustment, fits into a sort of socket on the base & seat support. And once someone sits in the chair, both ends of that cylinder become press fit, and near impossible to separate. I've been successful once years ago, when in a fit of stubbornness I spent about 8 hours beating on an IKEA chair to remove the cylinder & install a new one. In the end it wasn't technique, or a bigger hammer, but simple perseverance. I have either had a run of bad luck or a string of poorly made chairs over the last 15 years [I suspect the latter], plus with pain in my hips, I'm a bit more sensitive to foam padding collapsing/compressing, so I've gone through more than a few chairs. After my experience with that IKEA chair, when I've gotten rid of one I'll give it several good whacks with a hammer, just to make sure that cylinder's not coming loose, & then I'll give up.
Well, it was that time again, so after Lots of research I ordered a chair from Amazon. Concerned about disassembling it to fit in the box if I needed to return it, I tried anti-seize compound on the cylinder's 2 mating surfaces this time. 4 days later the lift cylinder gave out -- it would drop ~1" in 1/2 hour -- so I set about taking the chair apart. And after several good whacks with a dead blow hammer, the cylinder came loose (!). Now this was one chair after only a few days use, so I cannot say anti-seize cures the problem, but I will be using it on any future chairs, feeling that it at least gives me a chance the cylinder will come loose if I need to return it, replace the cylinder, or just make it easier to carry out to the trash.
I'll also buy anti-seize compound next time... For this 1st try I was skeptical, and Cheap, making my own DIY compound by mixing small bits of aluminum & steel with a gob of petroleum jelly. I used a Dremmel tool with a cutting wheel on scrap metal over a small container with some petroleum jelly in it, then mixed the result.