You do not say what size you are using but I will assume 1.1/2" just to answer this post.
Screwing these to items together will join a pipe, but are not particularly suitable for connecting to a boiler lid.
I believe that these are 1.1/2" BSPP threads, Brittish Standard Pipe threads with the last P standing for parallel. If they are BSPP, then there are "Backnuts" that will make a good connection to a lid.
All you will need are one male connectors of the type you have given the links for, and two 1.1/2" backnuts. Backnuts are available in brass or stainless steel, try googling "brass flanged back nuts"
I would suggest the following is easy to make and will provide a good seal. you will need one male connector, one brass back nut and one stainless back nut.
Take one 1.1/2" male adapter and screw on one Brass Back Nut - this will be pushed into the boiler from the outside. Then put one Stainless Back Nuts on the insde of the lid.
To seal it, solder the Brass Back Nut to the copper adapter, this will seal the threads, then use a suitable gasket between the Brass Back Nut and the outside of the boiler lid. Using this method there are no brass parts in the vapour path and not stainless steel to solder.
I would have made a sketch, but my PC has just crashed and I am in the middle of rebuilding it and have limited software. Let me know if you need any clarification.Statistics: Posted by YHB — Wed Sep 26, 2012 9:43 pm
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