Non taper thread vs Concrete tight

[Klockopotomis]

I typically use brand Bridgeport for non-taper thread fittings. A particular county requires all conduit fittings entering conduit bodies to be NTP. I don't see cross-hinds having a NTP fitting but rather "concrete-tight". Are these two terms the same? I need documentation for the AHJ

 

[infinity]

I don't think that the two terms mean the same thing. I cannot recall ever seeing a fitting with tapered threads.

 

[hbiss]

I need documentation for the AHJ

"Concrete tight" refers to the construction of the fitting so as not to allow slurry from the pour into the fitting and conduit. Nothing to do with the threads.

I can't ever recall seeing a fitting with tapered threads either. I don't think such a thing exists. How about asking the AHJ for a recommendation. Surely with every job in the county requiring them he should know just by looking what they are, right?

-Hal

 

[Klockopotomis]

Thanks for the input guys. From what I am finding, if the fitting it NPSM it does not make as much contact as NTP. Colorado Springs requires all hubs and conduit bodies NTP. I was hoping "concrete-tight" meant NPT. But I guess not unfortunately

 

[GoldDigger]

You are typing NTP when you mean National Pipe Thread, NPT.
The only fittings (couplers, adapters, etc.) that have tapered thread are plumbing parts, and you really do not want to use those.

 

[tburdick]

Condulets are tapered.
NPT. National Pipe Taper

 

[petersonra]

I typically use brand Bridgeport for non-taper thread fittings. A particular county requires all conduit fittings entering conduit bodies to be NTP. I don't see cross-hinds having a NTP fitting but rather "concrete-tight". Are these two terms the same? I need documentation for the AHJ

are you sure they are requiring it of fittings, or just the threaded conduit that threads into the conduit body.

 

[hbiss]

Condulets are tapered.

I think even the hubs on Bell Boxes are NPT. The female threads are not the problem. The OP is looking for FITTINGS with NPT male threads.

-Hal

 

[synchro]

These are relatively new and have an NPT male thread:

Connectors - EMT to Hub - Raintight - Compression - Connectors and Couplings - EMT Conduit Fittings

Bridgeport Fittings is an American-made electrical products manufacturer of couplings, conduit bodies, transition fittings and more.

www.bptfittings.com

As far as I know most, if not all, liquid tight fittings have an NPT male thread, for example in this drawing from Garvin Industries at :https://garvinindustries.com/pub/media/erp_files/images/Item Blueprints/ds-rte-75.pdf

 

[hbiss]

There you go! Wonder if somebody there owns stock in Bridgeport. $6.40 for a 1/2" EMT connector.

-Hal