NPT vs PT sizing

[Big T]

Hey all,

Did a quick search but the terms are too short to search for properly.

Just wondering the difference between NPT and PT sized threads? I currently have 2 temp and 1 pressure sensor all in 1/8 PT but every adapter ive looked at has 1/8 NPT sized holes. Does anyone know where adapters can be purchased with 1/8 PT thread sizing? Cheers.

Eddie.

[rob]

check this article originally posted by Mos

http://www.colder.com/Downloads/NPT.pdf

also lots of info on wikipedia search wiki for national pipe thread

[GA61XX]

Hey all,

Did a quick search but the terms are too short to search for properly.

Just wondering the difference between NPT and PT sized threads? I currently have 2 temp and 1 pressure sensor all in 1/8 PT but every adapter ive looked at has 1/8 NPT sized holes. Does anyone know where adapters can be purchased with 1/8 PT thread sizing? Cheers.

Eddie.

i thought that the threads were 1/8" BSP......
You could try your local hydrolic's shop, eg. Enzed, or Pirtec....
They should have an adaptor...

Q:- what motor they is on..??
I found that the toyota oil pressure was 1/8" BSP...
NPT is an American thread size...

cheers

[The Witzl]

i thought that the threads were 1/8" BSP......
You could try your local hydrolic's shop, eg. Enzed, or Pirtec....
They should have an adaptor...

Q:- what motor they is on..??
I found that the toyota oil pressure was 1/8" BSP...
NPT is an American thread size...

cheers

I've found that is true on my old 4AGE - the oil pressure sender thread was 1/8 BSP, so i got a BSP-NPT adaptor from Motorsport connections, seven hills.

On my 18R-G though, i can get a 1/8 NPT thread sender into the oil filter mount - so i dunno if all toyota engines have 1/8 BSP threads?

[Big T]

Cheers guys.

I finally figured out what the standard PT means... its actually the Japanese Industrial Standard for threads. I found an awesome PDF that shows thread interchangeability:

http://www.pneumation.ca/website_pdf...pipethread.pdf

JIS standards are basically the same as BSP which explains why all BSP threads will fit into our Jap made engines

Eddie.

[Talasas]

I've found that is true on my old 4AGE - the oil pressure sender thread was 1/8 BSP

I can confirm this.

http://www.toymods.net/forums/showthread.php?t=20467

[jeffro ra28]

BSP =British pipe thread?
NPT = National pipe thread?

One CAN (not ideal but still works) can be used in one but it wont work the other way round.
E.G. NPT wll go into BSP but BSP wont go into NPT. Or maybe its the other way around.

Never heard of JIS heard of JIC just not JIS. Whats JIS?

Oh, cheers for the chart BIG T thats awesome mate. Thanks!

[Steve M]

JIS is written on many alloy wheels

[jeffro ra28]

Arr ok cheers steve, what does it represent on a wheel tho?

[wilbo666]

JIS is the Japanese standard (Japanese Industrial Standard)

JIS pipe thread = BSP

Japanese Standards
PF - JIS Parallel Pipe Threads

PF threads are functionally interchangeable with BSPP. This is an old designations replaced with G.

Applicable Standards

* JIS B 202 PARALLEL PIPE THREADS
* ISO 228/1 PIPE THREADS PT 1: DESIGNATION, DIMENSIONS, TOLERANCE

PT - JIS Taper Pipe Threads

PT threads are functionally interchangeable with BSPT threads. This is an old designations replaced with and R and Rc.

Applicable Standards

* JIS B 0203 TAPER PIPE THREADS
* ISO 7/1 PIPE THREADS: DESIGNATION, DIMENSIONS/TOLERANCES

PS - JIS Parallel Internal Pipe Threads (to mate with PT threads)

Applicable Standards

* JIS B 0203 TAPER PIPE THREADS

http://www.engineeringtoolbox.com/th...rds-d_776.html



Cheers
Wilbo

[The Last Streetfighter]

I have found BSP and NPT to be interchangeable in practice at 1/8 and 1/4 sizes.
NPT is national pipe taper
BSP is British std pipe. Usually you have a BSPT OR BSPP taper or parallel designation.

[ed]

also here:
http://www.v-eight.com/tech_forum/viewtopic.php?t=123

[The Witzl]

when i tried to put an NPT threaded sender into the BSP threaded socket on my 4A-GE, it didnt go. I felt thread interference and so went and double checked with a fittings specialist who suggested i try the adaptor.

BSP-NPT adaptor = win.

[LeeRoy]

Arr ok cheers steve, what does it represent on a wheel tho?

If you are referring to an alloy wheel specifically one made in japan, the little logo present on them that says JIL or something like that is a stamp to say theyve passed tests aimed at testing theyre strength.

On a side note, american wheels are generally stronger than japanese ones as the tests put more force on the wheels than the japenese tests. In both tests though they put weight on the wheel and drop it at an angle at a predetermined height. Pretty sure this is because generally american cars are heavier than japanese ones.

[clubagreenie]

BSP =British pipe thread?
NPT = National pipe thread?

One CAN (not ideal but still works) can be used in one but it wont work the other way round.
E.G. NPT wll go into BSP but BSP wont go into NPT. Or maybe its the other way around.

Never heard of JIS heard of JIC just not JIS. Whats JIS?

Oh, cheers for the chart BIG T thats awesome mate. Thanks!

JIS = Jap Industrial Std
JIC = Joint Industries Council, a group that got together to "standardise" these things, and are probably still working on it. JIC is most commonly described for the 37.5 degree taper you see on the speedflow/earls/etc fittings.