Exhaust System on 80ft + workboats

Currently in the stages of designing an exhaust system for a SWATH which uses a twin servogear configuration of 4 x MAN D2862 - so far having trouble finding the most suitable components.

Does anyone have any ideas or advice.

Much appreciated


James Wickenden

 

Reckon dry stack? http://www.merequipment.com/products/em-exhaust-silencers.aspx

 

Dry stack is the way I want to go - just haven't had much experience designing boats over 40 ft...so 80 ft is a bit of a jump!!

Thanks for the link - it's given me more of an idea of what to look for.

James

 

If you can get Dave Gerr's Boat Mechanical Systems Handbook there's quite well explained dry stacks and keel coolers (they go together well..)

 

Pay particular attention to vibration isolation and the bellows for expansion and contraction. When you get to the actual component selection its pretty specific and best to call in a pro on exhaust.

Wet exhaust I know pretty well as I am in that business.

Steve

 

IF you use the dry stack , be sure to take advantage of the installation.

Interior heat , or at least Pilot House heat is easy , as is a hanging locker .

Also be sure to install a bypass thermostat in the keel coolant circuit to stop any chance of over cooling , which is destructive.

FF

 

Thanks for your replies Steve and Fred.

I'm looking into a similar arrangement as Red Jet 3 and 4, which run the Southampton-Cowes route. It looks like it has dry exhaust with a water injection point before it exits the craft.

James

 

I believe exhaust that exits at the waterline and is injected with water just before exit is not technically "dry stack," it's not dry and there's no stack.

Is noise an issue? Are you going to exit in the engine room hull side?

This arrangement can cause some noise and soot issues with the sides of the vessel, not sure with a SWATH configuration. I'm guessing the engines are in the "hulls" and perhaps even below the waterline?

If noise is an issue there are methods of exhausting dry cool and "cleaner" gas at the waterline than "straight pipes" getting hit with water at the hull plating.

Steve

 

Whenever I'm faced with an exhaust problem I call the guys that make the stuff.....Halyard in the UK, DeAngelo, Marine Exhaust, or Centek in the USA.....usually they end up designing the entire system......