Replacing basement shower and need drain help

[John Galt]

We have taken out the old basement shower pan and are ready to install the new pre-formed shower pan. When I removed the old one it was held in place by a threaded pipe that connected to the old shower pan. I don't have the old pan anymore so I can't say how it was connected. All I have is the old female threads that had a paper shim on top of it. The problem is that the only way I have found to install a shower drain in the basement is to have a 2" PVC pipe sticking up that can then have a compression fitting applied to it. The size of the female threads are about 3" in diameter. Is there an adapter that will screw into those threads and then be able to have a vertical 2" PVC pipe attached to that? The threaded piece that is there is welded to the original pipe in the floor, of course. I can see no way to remove the old threaded part without cutting it off and it's buried in concrete. I really don't want to cut the floor unless I absolutely have to. Does anyone make such an adaptor?

Thanks in advance, John

 

[Terry]

That's a big gap between the drain and the pan.
I think you will need to change out the drain to a new one, and if that means breaking some concrete, then yes, that will need to happen too.