Schedule 40 pvc underground exit schedule 80 pvc

[Jpflex]

Most projects I worked with kept the type of pvc consistent for the entire run. However I was wandering that due to cost what are some thoughts of going schedule 40 pvc for underground trenches to run wires and exit schedule 80 for exterior protection of wires. Obviously the inner diameter will be reduced on the end portions of the run in order to protect the wires and may affect pulling difficulty, overall conduit fill limitations, etc etc. also there is no special coupling fittings for this and the bell ends of the Taylor different rated PVC will connect correct?

 

[MTW]

For protection of the exposed above ground ends, when necessary ,I use steel rigid SCH40 with a bonding bushings at the termination ends.
In today's terms I can't speak to the cost difference, but the protection is better, and the fill rate stays the same.

 

[infinity]

Since the OD's are the same the bell ends should fit with either type of PVC.

 

[Jpflex]

Since the OD's are the same the bell ends should fit with either type of PVC.

That’s what I thought. What about the smaller inside diameter schedule 80 pvc? Wouldn’t this make the schedule 80 pvc required larger and therefore the entire project pvc sized up, to meet the at least the 40% conductor fill?

 

[tom baker]

If you are so close on fill that going to Sch 80 will put you over the fill limit, your conduit is too small. What the code allows for fill and what is practical are different

 

[Strathead]

That’s what I thought. What about the smaller inside diameter schedule 80 pvc? Wouldn’t this make the schedule 80 pvc required larger and therefore the entire project pvc sized up, to meet the at least the 40% conductor fill?

yes

 

[infinity]

That’s what I thought. What about the smaller inside diameter schedule 80 pvc? Wouldn’t this make the schedule 80 pvc required larger and therefore the entire project pvc sized up, to meet the at least the 40% conductor fill?

You would just use the Sch80 interior area for your fill calculations.

 

[Dsg319]

If you are so close on fill that going to Sch 80 will put you over the fill limit, your conduit is too small. What the code allows for fill and what is practical are different

I’ve learned that the hard way

 

[electrofelon]

You will want to put a nice chamfer on the schedule 80, unless you know which way you will be pulling

 

[LarryFine]

Conduit schedules are selectable in this conduit fill calculator:

Raceway Fill Calculator