Originally Posted by delmarrey
Yes better then just a plain thruhull, especially the thread crush. But they are still weaker then a full seacock when it comes to getting knocked off
, or if the valve gets stuck and pressure it applied. As well there are no drain/grease holes, unless special order. Especially important in the great white north on the hard
What is this statement based on? Which full seacocks are you comparing to? Some are thicker, and some are not. I have both physically tested these and made measurements of wall thickness compared to many "off the shelf" seacocks and don't find weakness to be of any issue.
If you've load tested these against other seacocks please let us know your findings?
Even in the smallest size flanged adapter, 3/4", the minimal wall thickness, at the threads, is twice
that of the next size up 1" bronze thru-hull and there are millions of boats out there with nothing more than a valve on a thru-hull. At the thru-hull to flange section even the smallest 3/4" flanged adapter has a 2.75 times thicker wall than the next LARGER size 1" thru-hull fitting. You then thread a thru-hull into this area and make it even stronger.
While not ideal the number of boats that have sunk because someone tried to turn a handle is quite small on bronze thru-hull/valve installs.
I know for a fact that a 3/4" valve threaded onto a 3/4" thru-hull will handle over 400 pounds of side load when loaded at the male adapter. I don't know too many folks that can apply 400 pounds of force to open a handle. This represents the weakest bronze fittings, a valve & thur-hull, that qualifies as a "seacock" by the ABYC definition.. While it does not meet the ABYC H-27 standard for strength it is still requires over 400 pounds of force to break one. The smallest flanged adapter is, at a minimum, twice as thick, at it's smallest & thinnest point, than the wall of a 1" bronze thru-hull.....
A 3/4" valve on a 3/4" thru-hull is the weakest installation
you can make other than the same set up in Marelon. In Marelon a 3/4" valve on a 3/4" thru-hull fails at under 200 pounds but in bronze it is slightly over 400 pounds...
I have never heard of a single
failure of a flanged adapter and you'd be hard pressed to apply more than 100 pounds pressure when turning a handle. If you've heard of a flanged adapter failure myself, others and I'm sure Groco would love to hear about it....