Hi Helder, from what I can see yours doesn't have any springs fitted. If you look at this thread
https://www.vintage-radio.net/forum/...=160632&page=2 Post #33 has an image of the type of valveholder with springs, which looks different to yours. You shouldn't do any damage removing the valves, but my advice to you is if you don't need to remove them, then don't! Cheers, Jerry