brass ball valves and bronze fittings

[Spyro]

I am intending to replace an old gatevalve. I have been advised to replace it with a ball valve, the only type I have came across are nickle plated brass are these ok to fit onto an existing bronze skin fitting?

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[tillergirl]

There has been quite a bit of recent discussion about these recently so if you search back in the threads you'll get a range of views. I suppose the general view could be summed up as the best seacocks are the bronze combined skin fitting and seacock such as made by Blakes but they are pricey and most people don't want to replace their skinfitting. So ball valves are the next best and for some quite good enough - however, as you have spotted most ball valves are brass which is not the best. If I remember correctly there was a reference in one of the threads to someone who supplied a bronze ball valve (beware of things described as manganese bronze - it's not a true bronze just brass - silicon bronze is good stuff). I've seen some ball valves at Volspec at Tollesbury (Essex) on display which looked like bronze but still had a white metal ball inside. I think the argument is that this is seated in Teflon and was therefore insulated. I need to replace my cockpit drains and was going to pop into Volspec and ask them what they were made of. But at the end of all this, would I be right in thinking that you're replacing the gate valves because the handles have gone while the body is still fine. In which case is corrosion really a problem? The gate valves have got to go because there are a poor design as a stopcock for a boat but it does make you think about the corrosion issue. For me, I wish I had bit the bullet and put in a couple of Blakes last time she was out - the toilet ones are original from 1964 and only need the old grease cleaning out at the beginning of the season and new grease applied and will still be fine in another 30 years. They are neater overall (you get the outlet offset, not poking straight into the boat as a gate or ball valve. However, I've got to change mine on the beach between tides this year so I think I shall try and get true bronze ball valves and wind them on the existing skin fittings.

I think that sums up the previous views - clear isn't it. If I'm wrong I'm sure others will add to this.

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[dickh]

You should try and fit Bronze Ball Valves - you'll find they have Stainless Steel balls with Teflon seats. Try <A target="_blank" HREF=http://www.asapsupplies.com>http://www.asapsupplies.com</A> who do them I think.
Ideally as I say use bronze but at the price of the nickel plated brass ones, you could afford to replace them , say, every few years. Don't forget the ball valves still have painted steel handles and these usually go first - the small square on the handle will sometimes round off the mating square on the valve and then you have to replace it anyway.

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I'd rather be sailing... /forums/images/icons/smile.gif