Did I miss something or do the pipe just magically reappear in your inventory when you need it in the underground vaults?
It looks to me like the same pipe you used to repair the water line with earlier. Now I was looking through my inventory for something to reach that socket with a there the pipe was again? Can't remember that I picked up another of those.

Ray automatically picks the pipe from the vault door, before he uses it to knock out Detective Bennet. So it's not the same pipe which Ed used earlier.