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BSPT pipe thread vs NPT "hands on" person?

mjwalsh

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I ordered something online & on their specification they said PT for the pipe thread ports on the device & like a dummy I assumed that meant NPT. No it turns out that is very likely BSPT. I did find adaptors to NPT that I can order from Ebay etc so I am not worried too much. 1/4" & 1/8"pipe thread converting involved. We are smart enough not to ruin the threads by forcing. Some gauges use the slightly different BSPT it appears. Live & learn I guess ...

I am thinking that Mac or someone here can give me a hint to where I would go within my city of about 100K to verify the threads.
 

MEP001

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Assuming you mean British Standard Pipe Taper, they're interchangeable with NPT as long as it's a fractional inch size and the thread pitch is the same, just use lots of Teflon® tape. You can tell pretty easily if the thread pitch is different by threading two fittings together by hand. They won't go easily more than a couple turns if they don't match.
 

mjwalsh

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There were a few hydraulic hose & parts suppliers here in our area who were familiar ... but it appears like the best a bit more detailed help was online in this case & was the following:


I got out one of my calipers & based on the ODs' & IDs' measurements... I ordered ... in this case from AliExpress some brass fittings that should work based on the ODs & IDs & the fact the spec described the threads as PT instead of NPT. I would have gone Ebay but I saved about $15 & it turned out that AliExpress shorter delivery time vs the potentially longer Ebay longer delivery time. I am not overly proud of :cautious: the non USA exception ... we will find out first hand about quality ... worse, same or better etc.

I did see an article that seemed to say that BSTP tapered male threads into BSTPP parallel female threads was preferred over taper to taper which seems to contradict the above guide that I linked!

Merry Christmas Everyone!
 

mjwalsh

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Just to follow up on the British Standard Pipe (BSP) adaptor need situation I had. A local nearby hydraulic hose (Parker Hose distributor & hydraulic specialty warehouse) had samplings of the 1/8 & 1/4 part ... but their sample fittings did not fit ... maybe mislabeled not sure. The Local Fastenal would have had to special order ... very expensive & no certainty on the exact taper. Thanks Mep001 for the teflon suggestion even though I did not follow the tip this time around.

I went ahead & took a chance on AliExpress ... the two fitting sizes that I needed & ordered turned to be a perfect fit ... apparently I got lucky that they sent the proper taper or parallel & exact pitch etc. Foreign buying direct more often than not ... seems to have communication difficulties with needed clarification of specifications etc. So ... maybe some of those middle men actually do earn their keep! In our case we hopefully should not have to use extra teflon based on the ease of the thread turn in match quality. The aluminum body of the air device items made me a bit wary about not using the exact thread match.

The items were the best fit for our somewhat experimental project. Considering the 24AC air switch solenoid coils matching the electrical & the other air controlled robotic type of a device. Finding a specific device that had attributes that seemed to be impossible or out of sight cost wise (20x etc) with searching USA vendors was the tipping scale to suffer through China or Hong Kong ... with the sometimes more perilous less assistance direct buy process. Usually Alibaba requires such a large quantity ... Aliexpress or Ebay ... not so much when it comes to quantity required. Also the Chinese extended very long holiday time period can be a standstill factor too.
 
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