From the prior page you may be familiar with shape of the flared ends of hydraulic pipes (photo at right). Below is a photo of a flare nut that has been over-tightened, resulting in the tube nose of the nut being flared outward like a bell end. This can make it difficult to remove if the flared out end interferes with the female thread. It may be even more difficult to get it reassembled later. If that flared end subsequently interferes with the cone surface seat in the port, then it may not screw together far enough to make the seal on the ball end of the tube. If you have enough length to the tube you might cut off the end and re-flare it, but you would be well advised to replace the flare nut at the same time. Otherwise start over and replace the whole pipe.

Thanks to Floyd Lawson for this picture.