2" pvc EXPANSION COUPLING

Status
Not open for further replies.

chris1971

Senior Member
Location
Usa
Quick question: I will be installing a 2" PVC expansion coupling this summer for an undergound service conduit and I was wondering what position I should put the coupling at in the summer? At the midway point which is marked on the coupling? I know this isn't a very technical question but, I haven't evervinstalled one before.
 

LarryFine

Master Electrician Electric Contractor Richmond VA
Location
Henrico County, VA
Occupation
Electrical Contractor
Consider that the conduit is longer now, increase the overlap (in the collapsed direction) to perhaps 2/3 to 3/4 of the travel. You don't want the sections to separate when it's cold.
 

satcom

Senior Member
i don't believe they are required underground.


You install them where the conduit comes out of the ground to allow for the seasonal movement, we see plenty of damage where they forget to install the fitting, don't forget to lay a sand bed where the conduit bends up, to allow the fitting to work.
 
Last edited:

infinity

Moderator
Staff member
Location
New Jersey
Occupation
Journeyman Electrician
Is this expansion fitting for pipe expanding or for ground settling? For the latter in the summer I would install it all of the way in.
 

cpal

Senior Member
Location
MA
You install them where the conduit comes out of the ground to allow for the seasonal movement, we see plenty of damage where they forget to install the fitting, don't forget to lay a sand bed where the conduit bends up, to allow the fitting to work.[/quote

Is the op's coupling listed for thermal of ground movement???
 

nakulak

Senior Member
when installing something you havent' done before, it's always good to read the instructions.

generally, with expansion fittings, compare the temperature you are installing in (current conditions) to the extreme conditions that might occur.

in other words, if you are in the desert installing the in the middle of summer at noon, you would be installing when the conduit was expanded the most it would ever expand. If you are installing on the coldest day of the year, you would be installing at the most contracted point. If you are roughly midway temperature wise, then the middle marker is exactly correct.
 

Volta

Senior Member
Location
Columbus, Ohio
Is this expansion fitting for pipe expanding or for ground settling? For the latter in the summer I would install it all of the way in.

Exactly.

If the trench bed will settle over time, push the fitting closed. I find much less trouble with frost heaves than settling. Your area may be different.

The temperature change of the PVC itself is not likely a factor here, as the length from the frost line to the LB or similar often is short.
 

satcom

Senior Member

greeny

Member
Location
Southern NH
I've read this thread and looked at the links but I didn't see what I was looking for. Where would you want to put the fitting for movement of the earth(like for the meter slips)? Not settling or thermal expansion/contraction, but for frost heaves, etc.
During the summer, I would think you'd want it set at 1/4 to 3/8 to allow the earth to move up during the winter.
 

satcom

Senior Member
I've read this thread and looked at the links but I didn't see what I was looking for. Where would you want to put the fitting for movement of the earth(like for the meter slips)? Not settling or thermal expansion/contraction, but for frost heaves, etc.
During the summer, I would think you'd want it set at 1/4 to 3/8 to allow the earth to move up during the winter.

Try 6 to 10 inches in some areas, follow the manufactures recommended slip.
 
Status
Not open for further replies.
Top