dpb wrote:
RogerT wrote:
Here's the follow-up answer:
...
They came out today and I asked them what the fitting is. They said
it is called a "posilock" fitting. It is used because the old steel
gas lines that came into buildings are no longer used for gas supply.
Instead, the steel pipe is now used as a conduit. Inside the steel
conduit is a plastic gas supply line that comes in from the street. The
posilock fitting connects the plastic gas supply line to the gas
line that is inside the building that goes to the meter.

I did a bunch of Google searches on posilock etc. and I still
couldn't find too much additional information, but here's what I did
find: "posilock transition fitting"

http://www.flowersareforever.org/art...tober42002.htm

Inner-Tite (manufacturer?)

"The posilock seals together the larger plastic pipe from the street
to a smaller metal pipe in the basement of a home or business."
...
Interesting.

Here's link to Inner-Tite who does list the trademark but I see no
hint of the particular product/fitting. One might presume it was
recalled/abandoned as a not-so-good idea, maybe.

www.inner-tite.com/home.htm

At least there's a rational explanation for what it looks like
although might be some reason to be at least vigilant if not
necessarily nervous.

Well, here's a new twist on the whole question of what it is. I am having a
minor relocation of the meters done (by about one foot up and one foot over
to the right). The first street 90 was taken off, but the silver color
fitting and the straight brown fitting that it is attached to were left in
place. I was not there, but the person doing the work looked inside the
supply pipe coming through the wall. He said it is nothing but a hollow
steel pipe -- no plastic gas line inside, etc.

So, the person who told me that the silver fitting was a "posilock" that
connects to a plastic gas supply line that is inside the steel pipe was
mistaken.

It did occur to me that at least one (and probably two) of the 3 properties
I have that all had the silver fitting have NOT had any new gas supply
service line run into the building in many many years -- at least back to
long before they ever began using plastic gas supply lines. The third
property that I looked at that also has the silver fitting did have a new
gas supply line put in about 3 or 4 years ago, so that one may have a
plastic gas line inside of the steel pipe -- I don't know.

But, my guess now is that the silver fitting serves some other purpose --
possibly/probably as an insulator or dielectric device, as others here have
suggested.

I am going to keep asking gas company people and anyone else I can find in
the future. The mystery remains unsolved for now.