Wet Exhaust stainless.?

Hi,
Can someone advise me as to materials for a water trap.
I need to fabricate one to fit in a specific place.
I tried a Vetus plastic one, but it just didn't sit right.

I found an article which says super duplex would be bullet proof, but, a colleague at work says nickel and sulphur don't go well.
Would 316 SS be a good choice.?

thanks
Howard

 

Stainless doesnt hold up well in the exhaust system.

Did you review what Halyard has to offer ?

http://www.halyard.eu.com/

 

Thanks Michael,
I have looked at Halyard, still too big.

It really has to be fabricated to fit my space.
I have re-engine and gone up to a two-cylinder, hence less space.

The hoses contain a maximum of 2 litres, so I was going for a 4 litre size box, which needs to be narrow, to fit the remaining space.

Would the corrosion be rampant ?
If I made a spare at the same time and did an inspection/swapover annually I think I would be OK.

 

check out Centek.
If you make you own from metal try CuproNickel .steel

 

The problem with stainless is that it needs oxygen to stay in the passive state. Standing water in the bottom of your exhaust causes trouble.

If you must use stainless choose a thick gauge of ss for the bottom and sides....places that you know water will stand.

Carefull welding...no void, pin holes. Ask a specialist.

Ive had several ss aqaulifts over the years...they all failed over time. Inspect regularly

You might ask a glass guy how to build one grp. The construction is simple. The complication is that the exhaust system must withstand high temp in the event of a cooling system failure

High temp resin is used.

 

Thanks for the input,
I am going for 316, maybe I can automatically slow drain the waterlock when left for some time to get oxygen in.

The Cupro nickel was an idea but apparently is very hazardous to the health.

I will also have a look at moulding one from glass, that would be quite easy.

 

Our welding shop has duplicated quite a few stainless steel sailboat wet exhaust muffler assemblies that had developed pinholes from years of corrosion. We use 316L exclusively and wherever possible, especially the jacketed section of the exhaust pipe where a pinhole assures water drainboard in to the engine exhaust will occur, use thicker material than was used in the originals.

We did quite a few of them for older Nautor Swan's, for some reason. Not sure if it was the age or that they had originally used an inferior grade of stainless..or both?

 

Hi Howard,
I see that you have mentioned the 316 in two separate posts, so it is probably not a typo. Since the manufacturing of the wet exhaust will require a lots of welding, I would suggest you to use the 316L (and not 316). SS 316L is the low-carbon variant of the SS 316. Having a low carbon content, the chromium-carbide precipitation in the welded parts of the 316L is significantly reduced and the chrome content is preserved. It gives a better corrosion resistance to the welded areas of the 316L, when compared to 316.
Cheers

 

Slavi
It's not really an issue with thin wall sections, they cool too quickly to get carbide precipitation. But 316L is marginally better for general corrosion in a wet exhaust but not by much.