I had a little water leak at my cottage and had to change out some piping. I used some pex and sharkbites and they worked great. At least for keeping the water contained, which is probably 99% of good plumbing. Anyway, I changed my old master shut off tap for my outside hose to a sharkbite ball valve. Again the tap works great but when you turn on the hose or pull on the hose, the bib rotates. I believe it is rotating on the sharkbite fitting inside the cottage. The sharkbite is biting down on 1/2 inch copper on both ends, with the end by the wall going through to the hose bib outside. This rotation is not creating a leak but I worry that with constant rotation, when it's used, that it might. My question then is, do you think this rotation might create a problem in the future and if so does anyone have any ideas on how to stop it from rotating.

I want to block a water pipe that is under pressure. I am working on a house in Central America with a damaged water pipe under the sink. The damaged pipe formerly had a steel pipe threades into it. The steel pipe corroded and attempts to remove it left the corroded threaded part of the steel pipe stuck inside. After extensive attempts to remove the corroded pipe from the threads, I decided to block the pipe. (There is another line next to it, and houses here dont plumb hot water to sinks, if they have it at all, so only one line is needed.) I tried the following to block the pipe: 1) Stuffed some plastic bags down it 2) filled a PVC cap with a cement designed to cure after 10-15 mins. Painted the concrete wall with concrete adhesive & put the cement-filled cap over the pipe. The idea was to cap the line with concrete and forget about it. After letting the cement cure for 2 hours (adverised time 10-15 mins), I turned the water pressure back on. Looked fine for 10 mins but then started dripping. How can I block this water line? (assume that I can use a cutting wheel or drill with appropriate bit to remove the concrete cap).