First... come up with a subject for the subject line and a question for the post... just to keep things a bit more professional as you work towards your Journeyman status. Remember, these electronic characters we're typing don't cost much.
It would help a lot if you were to describe the fittings and their application a bit more. I suspect that the HxH is a designation of end connections, but what it may mean isn't occurring to me. For example, you might get a fitting which is SWxTHD which would indicate socket welded on one side and threaded on the other. This type of callout often comes up on extended body valves used for vents and drains or gages. The valve is socket welded into a Sockolet type fitting and typically plugged with a threaded plug or they may have a gage inserted.
So, how are these fittings being attached to the piping?
After looking at all the fittings shown on the pdf file I think the "H" in "HxH" (etc.) stands for "Hub".
These fittings are Hub by Hub (elbow) or Hub by Hub By Hub (Tee)
In gravity rated DWV (drain, waste or vented) “HxH” is the classification for those fittings that have a bell-shaped section at each end. H stands for hub. Those fittings that have a bell-shaped section at one of their end and a straight section at the other are classified as “HxS”. S stands for spigot. These classifications are not use just for schedule 80.
jte: I was not aware about the existence of a city named Ione, I am from Italy. And yes they are solved welded fittings
