metric pipe thread

[admiralslater]

On our Outremer I have seacock that needs replacing. It is the feed to the watermaker.I am in France at the moment and was looking in the Chandlers and found one that appears to be correct. The guy said it would match the pipe threads on the thru hull. I looked closely at the valve and it was marked 1/2 inch. Several others where labeled the same way.
My question is, is pipe thread universal ie imperial. If not is it common for french builders to us. Imperial threads.

[double u]

it's imperial in metric austria & germany, so I think in froggyland too

[dlymn]

Europe is mostly metric. You might be able to get an imperial seacock flown over from a US chandler or you might replace all parts up to the hose. If it's 1/2 inch, you should be able to get a seal on 12 mm nut and tail even though it's slightly smaller. Most imperial hoses have a similar sized metric equivalent. You might try a UK chandler as they might stock imperial parts for old boats. In Aus we have been metric for over 40 years but they still sell imperial nuts and bolts in hardware stores.Timber is sold in multiples of 300mm because that's close to the old foot measurement.

[Teknishn]

Am currently working a boat restoration project in Egypt and have had to deal with the metric vs. SAE issue on numerous occasions. All of our valves and piping are 1/2", 3/4", etc., up to 5-inches. However, the threads for said pipng and valves are all metric which doesn't mate well with SAE fittings. What I did was to order a bunch of pipe nipples from the States in the sizes that we needed and then, using these as samples, had local machine shops manufacture what we needed. Cheap to do in Egypt, probably not so cheap in France though.

[double u]

biggest german mailorder:
https://www.svb.de/de/edelstahl-muffenkugelhaehne.html
all imperial
working here for austria's bigegst distributor: everything imperial.
show me ONE metric seacock/ballvalve, dlymn!

[Siberianhusky]

"Metric" pipe thread would be labeled as ISO or DIN, they are interchangable with each other - different numbering system.
While you may be able to get them forced together the threads are NOT the same as NP or NPT which are imperial.
Gets confusing in Canada which is metric but there is so much imperial still being used, especially in the trades. We still work almost entirely in imperial. I don't even own a tape measure with metric markings.

[double u]

so please someone post me a link to an easily available (at any sort of on- or offline chandlery) METRIC SEACOCK!

[Zai]

You are probably looking at BSP or BSPT (European standard) threads, which are close to but not compatible with NPT (US standard) threads.

[30yearslater]

I'm going to muddy the waters a bit further. I work with hydraulic systems from the international community. There are 4 threads that you are most likely dealing with in your application. NPT = National Pipe Taper thread. This will have 3/4" per foot taper. NPS = National Pipe Straight thread. BSP = British Standard Pipe. Tapered similar to NPT. BSPP = British Standard Parallel Pipe. Similar to BSP without the taper. NPT/NPS in the 1/2" size has 14 threads per inch as do BSP/BSPP. Let's start there.

[admiralslater]

Well will miracles ever cease. We just came back from the Outremer factory in LA Grande Motte and not only did they have new old stock on the hinges and interior lighting but when th showed m the replacement seacocks they where labeled in mpt so standard for my side of the world.
FYI they have sold 26 45s and 16 5xs in two years

[Cheechako]

It should be straight thread not pipe thread right?

[admiralslater]

Sorry thick thumbs ,labeled 1/2 inch and they are straight threads.

[Badsanta]

My boat from the factory had tapered seacock to straight threaded thru hull. Only held bu 2 turns. I replaced all. Dont mix straight threads with tapered threads. A Groco flange adapter is your best friend.

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[steveman8]

I found this quick article that says BSPP and BSPT hydraulic fittings are commonly used in France. Hope that helps!