Can I use a compression flange on clay sewage line

[MacB]

I'm replacing a bad flange for the toilet. I wanted to use the oatey compression closet flange with the 3 allen head screws inside :
http://www.oatey.com/products/drains-and-closet-flanges/closet-flanges/replacement-closet-flange
Just wondering how fragile the clay drain pipe is? As long as I don't over tighten it, do I have to worry about it breaking the clay drain pipe? What if the pipe wasn't installed perfectly straight (which I don't believe it is)? The house is on a slab so can't afford to break the clay pipe.

Thank you

 

[Mr_David]

Truth is, I would not even use that on a good castiron pipe.
For clay pipe I would say No way.

structural strength of the clay pipe is pretty sound when using a clamp on the outside. You can exert a lot of compression force inward like and arch over a door way in masonry constuctruction.

But exerting an internal force outward inside a clay pipe, I think, would easily crack it.

I have never seen a clay closet bend. How does the old flange attach to it?
Pictures??