This is Polyethylene
This pipe is only about 6 years old. As I mentioned I have had problems with leaking on both ends of this ( at meter and where it goes into pool equipment) Luckily both of these connections are outside. Remeber this pipe is being used after the meter, so it is at very low pressure, but I was still getting leaks.
Instead of trying to tighten the compression fitting, I took it apart to see if I could tell what was wrong. The fitting was very heavy duty metal, probably weighs a few pounds, but it is a pretty basic compression fitting. There is a metal flange about 6 inches long that slips inside of the pipe, then there are the two parts of the compression fitting and a rubber gasket which has some metal embeded ( I assume to keep it from deforming too much ). The thing that was odd when I took it apart was that the gasket was on a metal sleeve which then was on the outside of the pipe. When I looked at this it seemed that the metal sleeve would keep the gasket from sealing against the pipe. The more I looked at it, it seemed like this metal sleeve didn't belong and it was possibly just used to keep the gasket in shape during shipping.
I took that outside metal sleeve off and the fitting works perfect, no leaks. I have checked it a few times over the weekend, and still no leaks. If this were inside, I wouldn't be messing with it like this, but it is outside, and seems to be working perfectly.
Hopefully my discussion of this isn't too confusing. Anyone have any thoughts.
Thanks,
Ron