NPT to AN Converision Chart
 

Can someone post up a conversion chart between AN and NPT. I need to know what 1/16" NPT and 1/8" NPT would convert to for AN.

I think it would be handy if this conversion chart was stickied for everyone.

Thanks!

John

There is no set conversion, you can get AN to pipe thread adapters in a wide range of combinations. There is no one NPT size which corresponds to a given AN size and it varies vendor to vendor.

For instance, XRP makes NPT to -8AN adapters with 1/4, 3/8, 1/2, and 3/4" pipe NPT sides.

One issue to watch for though is usually for any given size AN adapter, the smallest NPT adapters will have less than optimal ID's because the pipe thread size is on the small side.

Case in point, take a 1/4" NPT to -8AN adapter. The nominal ID of -8AN is 1/2". However, 1/4" pipe thread is only .540" OD; by the time you subtract the wall thickness of the fitting from that .540" it is no longer a "full flow" adapter fitting.

They are two different threads so I'm not sure what you're trying to compare. In 1/2" npt you can get adaptors to go from #4 through #16 AN, all going to the same 1/2" npt. Are you asking which AN thread is the closest to a particular NPT, even though there are none that are the same?

Jody

i assume hes asking which npt sizes are close to each a.n size.
most of the a.n fitting companys, aeroquip, Russell etc provide a diagram in there catalogs, looks for one online.

John
There is no conversion. Pipe thread is pipe thread which is a tapered thread and seals on the thread hence pipe tape pipe dope which is used to seal the thread. The taper is what seals and the tape or dope help from any liquid or air bypass. AN adapters and fittings are a strait thread. These types of fittings seal on a surface weather it be on the degree of the male and female contact point (37 or 45 degree)or on the actual surface where the nut would come into contact. Thats where you would use a crush washer or o-ring. In relation to pipe and AN in our industry everything is based in 1/16's of an inch. I don't no of any or have never used a - size smaller than -2 which is 1/8" in relation.
The sizes are as follows. 1/8= -2 which is 1/8 pipe, 3/16= -3 no pipe size 1/4= -4 which is 1/4 pipe, 5/16= -5 no pipe size, 3/8= -6 which is 3/8 pipe, 1/2= -8 which is 1/2 pipe, 5/8= -10 no pipe, 3/4= -12 which is 3/4 pipe, -14= 7/8 no pipe, -16= 1" which is 1" pipe, and so on. These are the most common used in our industry. Hope this makes it clear.

You might be meaning
1/8" = #2
3/16" = #3
1/4" = #4
3/8" = #6
1/2" = #8
5/8" = #10
3/4" = #12
1" = #16
1 1/4" #20
1 1/2" #24

This might help you out.It is pretty much an industry standard.

Rodger

Ok Roger quit trying to one-up me!!! LOL. By the way answer your phone. I have the frame rails ready

The AN size to fractional size have been posted but in case you don't want to memerize them it works in 16ths

example -6 is 6/16=3/8

http://www.bmrs.net/ti-6.htm

just realize that with the common braided steel over rubber line they actually come out smaller than this. I think in teflon lined hose it's probably more accurate. For example, #8 braided line is closer to 3/8" id than it is to 1/2" id. #6 is closer to 5/16" id, and so on.

Jody

My phone has not rang all day. I was at the track all after noon.

Rodger

I think Rodger hit upon what I was looking for but I found this which pretty much explains it.

http://www.chevellestuff.com/tech/an_fittings.htm

Basically, I want to pull a schraeder valve from a fuel rail and run a Fuel Pressure gauge on the rail. The schraeder valve is 1/16" male NPT and the Fuel Pressure Gauge runs a 1/8" female NPT. I was trying to locate a 45* aluminum adapter rather than a straight brass one.

John

Rodger,
I rang the wrong phone.


John,
Good luck trying to find it in a 45. Either Godman high performance or Pure choice motorsports I think has that adapter in a strait. Or you can go to a local auto parts store with an Edelman brass air hose fitting selection. Take a fitting that has a 1/8" compression hose to 1/8 pipe female adpter like in your autometer oil pressure kits. Unscrew the hose side and if I remeber correctly that thread will screw into the shraider hole. From there you can put a 45 on it but it might start to look ugly being that long. Hope this helps.

Thanks but, yeah, just too many adapters on top of adapters. I wanted to find a tee that had a 1/16" male NPT-1/16" female npt-1/8" female NPT. This way I could use the 1/16" Male NPT where the schraeder valve was and move the scrhaeder to the 1/16" female NPT and put the fuel pressure gauge on the 1/8" NPT.

John

The standard it does not specify inside diameters do to varying wall thickness. The sizing system works off OD.
http://en.wikipedia.org/wiki/AN_fitting

exactly. I know you're aware of this but my post was for those who weren't. If they have a 3/8" steel barb and wanted to add some braided line to it to go to the carb for example, by that chart they'd buy #6 and it would be almost impossible to get it on the barb, id too small. #8 would be the correct choice. Just trying to save someone from buying the wrong stuff.

Jody

I got you this can be very confusing to those who don't know how it works. I have been fortunate enough be work closely with Brown and Miller Racing Solutions BMRS. They supply most of the hoses used in nascar as well as the American la Mans series. They have always strengthen me out and explain how things should work when I get confused.

I do it on a regular base. Try making your own fitting. Find the proper fittings that your going to use cut them apart and silver soder them together. This way you can make your tee that you want

Mark