[time-nuts] OT Euro/US plumbing was 14 tpi UNS die

[Chuck Harris]

Joseph M Gwinn wrote:
>
> The relevant US pipe-thread standards are quite clear - straight threads 
> are for mechanical connections only.  For connections that must also 
> contain fluids under pressure, one uses taper threads such as the 
> ubiquitous NPT.  Over the decades, I have lived in many houses, including 
> my current house, with circulating hot water heat and cast iron radiators, 
> and I have never had to redo a radiator connection.  I've never had a 
> leak, and most of these systems were old when I bought the house. 
> 
> If you have straight pipe threads going into radiators, there is an 
> installer who should be made to re-do the job.  Maybe he was an 
> out-of-work electrician, and used rigid electrical conduit for pipe.

Sorry, but the European radiators, manifolds, fittings and valves that are
coming into the US for use in hydronic heating systems are all straight pipe
thread with O-rings and jamb nuts, and that is  the reason for my mentioning
of that fact.

They are exactly as I described them.

> 
> Straight threads and O rings are seen only in hydraulic systems, not 
> domestic water or heating systems, and the mating parts have correctly 
> designed pockets to hold the O-rings.  And they do not use jam nuts.  One 
> screws them together until they bottom.

I understand that, tell that to the European heating manufacturers.

Time to get back to time.

-Chuck Harris