BSP Threads

[Argonaut]

Looking for advice on the suitability of a BSP fitting.

My need is to fit a 1" BSP male thread into a clearance hole is a thin(ish) plate and fix it there with a nut either side of the plate
One of these : https://www.oilybits.com/316-stainless- ... b-bsp.html

My question is the Male threads are BSPT (not BSPP)
Will a standard 1" BSP nut hold on a 1" BSP tapered thread.

I have no experience of Taper threads so unsure.

This does not have to be a water tight seal, I can use PTFE is required, my only concern is the physical fitting. (it's blowing low-pressure air through fitting)

 

[jimmy_s]

Normally it holds ok. Only experience I have is BSPP pipe fitting onto BSP taper fitting - holds with some PTFE or Boss White/ hemp. 2nd nut on the more tapered part might be loose but with plenty of PTFE should be fine. Other option might be to weld a nut or half socket to your sheet and screw fitting to that. You would get a BSPT Socket or use BSPT socket on the tapered end and a back nut if you want it to be less shoogly.

 

[sunnybob]

https://www.amazon.co.uk/BSP-Storage-Ta ... B00FA38L7Q

 

[sunnybob]

They are available in brass if its for medium high pressure.

 

[Argonaut]

https://www.amazon.co.uk/BSP-Storage-Tank-Water-connector/dp/B00FA38L7Q

It has to be a metal fitting .. brass os SS due to temp

 

[Argonaut]

Normally it holds ok. Only experience I have is BSPP pipe fitting onto BSP taper fitting - holds with some PTFE or Boss White/ hemp. 2nd nut on the more tapered part might be loose but with plenty of PTFE should be fine. Other option might be to weld a nut or half socket to your sheet and screw fitting to that. You would get a BSPT Socket or use BSPT socket on the tapered end and a back nut if you want it to be less shoogly.

I can't weld .. as plate is chrome plated, and fitting is stainless ... though PTFE tape or any other hi-temp tape would be OK

 

[Argonaut]

They are available in brass if its for medium high pressure.

That is what I was thinking of using 2 x brass nuts on SS male threads ... not perfect as dissimilar metals ... but fine for me

 

[AndyT]

Is this what you need?

https://www.midlandchandlers.co.uk/prod ... ass-ad-022

 

[Argonaut]

Not really.
What I would like 'ideally' is 1" BSP M to F 45 degree in brass ... but they are VERY expensive.

Plus the M threads are BSPT which is not ideal for using a lock nut.

Plan B is I will probably go with 45 degree F to F elbow ... and insert a 1" BSP barrel nipple into one end.
I can get these in stainless steel for around £5.50

 

[Eric The Viking]

Do appearances matter, or is this just 'to get you there'?

Copper with SS or Chrome ought to be OK - so can you use conventional plumbing fittings and silver solder (AKA braze) them, or possibly just solder them? Lead-free solder melts at around 200 deg C (it does depend on the type tho), and ornery 60:40 tin-lead around 180 degC - might that be enough?

I'd certainly use a tank fitting of some sort on the hole in the plate, but there's a much wider range available in brass, and if you are worried, I'm fairly certain that most tank fittings are parallel rather than gas-taper, so nuts will work normally (I've got both sorts, I think). The 45deg angle is more challenging, but that can be achieved by neat soldering or brazing.

I needed, but couldn't find gas taper fittings recently, as I'm refurbishing our solar HW system. I ordered some flow meters from China:

but when they came the threads were all wrong (they were cheap!). Specifically things that ought to have been BSP (gas taper) weren't, but were parallel instead. It's been a really awkward job getting them to seal correctly (done it now).

On one end I've used 15mm compression to 1/2" pipe thread spigots - they look like a 15mm compression coupler, but the second end has no cone. These, too, should be gas taper BSP, but they aren't, and I couldn't get gas taper ones from any of the usual suspects. Obviously a tapered thread is more expensive to make, so it seems the manufacturers don't bother any more for mass-market stuff. You can't always fix this problem with PTFE tape!

 

[Inspector]

Try looking into 45º bulkhead fittings for hydraulics. Here are lots designed to be bolted through sheet metal. The nut side will be straight threads and the opposite side will be straight/tapered, male or female, or even barbed. Only rub will be the costs are higher than the plumbing fittings you've been looking at.

Pete

 

[jimmy_s]

Could you use a brass tank connector? - should be able to get one with a BSP end or compression copper if that's handier to connect to with your other pipe