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Old October 12th 14, 04:49 AM posted to rec.boats.building
[email protected] bruceinbangkok@invalid.com is offline
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First recorded activity by BoatBanter: Jul 2014
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Default NPT and BSP taper threads

On Sat, 11 Oct 2014 03:58:07 -0700 (PDT), wrote:

2009 m. spalis 21 d., tre?iadienis 22:13:51 UTC+8, CS raš?:
I am looking at getting some water filters, 20 inch housings, with 3/4
inch NPT female connections in plastic tops. Can I get away with
screwing in 3/4 BSP TAPER male brass compression fittings, using a
good wind of PTFE tape??
Both NPT and BSPT are 14 TPI and the nominal NPT is 1.050 inch OD and
BSPT is
fractionally smaller at 1.041 inch OD, so should fit in. I know that
there is a 5 degree difference between thread angle.

TVMIA


WHAT FITTING I WILL USE IN BSP IF THE OUTSIDE DIAMETER OF MY PIPE WITH THREAD IS 21MM?


U.S. Standard 1/2 inch taper pipe thread has a OD of 0.840 inch and 14
threads per inch
British standard taper pipe thread has an OD of 0.825 inch and 14
threads per inch.
Your measurement of 21 MM is equal to 0.826 inch.

As taper pipe threads are, of course, tapered, your US and British
standard pipe threads will certainly screw together with no problems.
--
Cheers,

Bruce in Bangkok