RGC Schedule 40

[Alwayslearningelec]

I saw this on a drawings( RGC schedule 40). I believe this is incorrect and they either mesnt PVC sched 40 or RGS. I know there is PVC coated RGS but I don't think that's what they meant. DO you agree? THanks.

 

[Strife]

Keep in mind we always recycle our lines when we write. Especially when it a 200 page document that only needs 2-3 changes. So that's probably how the Sch 40 came about (replace what? VC, with what? GRC)

And last, that's why we have RFI's

To answer your question, no I seriously doubt there's such thing as GRC Sch 40. The schedule on PVC is about wall thickness, so it has noting to do with coating.

I saw this on a drawings( RGC schedule 40). I believe this is incorrect and they either mesnt PVC sched 40 or RGS. I know there is PVC coated RGS but I don't think that's what they meant. DO you agree? THanks.

 

[don_resqcapt19]

GRC is often called schedule 40. The wall thickness of conduit is approximately the same as the wall thickness of schedule 40 pipe.

 

[LarryFine]

To answer your question, no I seriously doubt there's such thing as GRC Sch 40.

That's incorrect. Rigid uses Schedule 40 et al like other pipes.

 

[Smart $]

That's incorrect. Rigid uses Schedule 40 et al like other pipes.

Rigid metallic conduit does not have "schedule" sizing. Metal pipe and conduit are sized to different standards even though some sizes may be very similar (as noted by Don). There is no schedule sizing in the standards for metallic conduits.

 

[LarryFine]

Rigid metallic conduit does not have "schedule" sizing.

Well, it used to. Other steel pipe is still specified that way.

 

[jmellc]

PVC is the only conduit I've seen with schedule ratings.

Have to watch terminology too, it changes a lot, goes & comes around. I struggled a moment just now with GRC, then thought, yea galvanized rigid conduit. I usually see it termed RMC, rigid metal conduit. I thought all rigid was galvanized, am I wrong on that?

I see PVC termed as RNC, rigid nonmetallic conduit.

We use to call sealtight any flexible WP conduit, said metal sealtight or nonmetal.
Now the metallic is usually called sealtight & nonmetallic is called Carlon.

 

[Smart $]

... I thought all rigid was galvanized, am I wrong on that?

...

Yes, you are wrong. Other metal types (e.g. aluminum, brass) are not galvanized. The G in GRC implies steel rigid conduit, sometimes acronym-ized as GSRC, but steel conduit is always galvanized, and vice versa.

 

[BJ Conner]

It's all schedule 40

It's all schedule 40

Yes, you are wrong. Other metal types (e.g. aluminum, brass) are not galvanized. The G in GRC implies steel rigid conduit, sometimes acronym-ized as GSRC, but steel conduit is always galvanized, and vice versa.

All rigid conduit is dimensionally the same as Schedule 40 pipe -with the exception of coupling threads which are straight ( not tapered).
Steel conduit can be finished with Enamel or Sherardized ( although I haven't seen any for 40 years). It can also be brass, stainless steel or Mu-metal ( all can be had for mere money).
I have seen one accident where some idiot tried to build a temporary air filter using a section of 4" GRSC. He put cotton in it and then rigged it into an 80 PSI line. It didn't blow up but the seam opened real fast.
Conduit is fabricated with a seam and SHOULD NEVER BE USED AS PIPE. IT'S DANGEROUS TO PUT ANY PRESSURE IN IT.

 

[jmellc]

Yes, you are wrong. Other metal types (e.g. aluminum, brass) are not galvanized. The G in GRC implies steel rigid conduit, sometimes acronym-ized as GSRC, but steel conduit is always galvanized, and vice versa.

I knew aluminum was not galvanized, I've used a little of it in the past. Never used brass or stainless, though I know they can be had.

 

[Smart $]

All rigid conduit is dimensionally the same as Schedule 40 pipe -with the exception of coupling threads which are straight ( not tapered)...

Rigid metallic conduit is not "exactly" the same as Schedule 40 steel pipe!!!

Take for example 1" trade size...

Nominal OD Wall
RMC 1.315" 0.126"
Pipe 1.315" 0.133"

FWIW, all nominal OD dim's are the same.

 

[LarryFine]

FWIW, all nominal OD dim's are the same.

Yep! Always larger than the ID. :grin:

 

[220/221]

They make galvanized rigid pipe smaller than schedule 40 (think fence pipe) but I've never seen galvanized rigid conduit in anything other than schedule 40.

 

[BJ Conner]

Enameled on the inside

Enameled on the inside

Rigid metallic conduit is not "exactly" the same as Schedule 40 steel pipe!!!

Take for example 1" trade size...

Nominal OD Wall
RMC 1.315" 0.126"
Pipe 1.315" 0.133"

FWIW, all nominal OD dim's are the same.

How thiick is the enamel coating on the inside?

 

[LarryFine]

They make galvanized rigid pipe smaller than schedule 40 (think fence pipe) but I've never seen galvanized rigid conduit in anything other than schedule 40.

I could swear I have seen RGC in Sched. 80, but Smart $ said RGS doesn't use that system of specification.

 

[Smart $]

How thiick is the enamel coating on the inside?

The standard does not say for certain, but I believe all coatings are included in the dimensions. Thicknesses of coatings other than zinc are specified in UL 6.

 

[stevenj76]

Horsegoer sounds right. I'll bet its Sch. 40 PVC.