Insulation Material to be used on diesel exhaust

[PEDARRIN2]

I need to know what type of insulation and a good idea of how thick to use to insulate the exhaust of a diesel driven fire pump.

The project requires this pump to be on the interior so I need to be concerned with the fire risk of the hot surface.

The manufacturer states that the exhaust temperature will be about 1100 F.

I am familiar with insulating hot water piping so this is outside my expertise.

Please help.

 

[Zapster]

calcium silicate is good to 1200 degF
Johns-Manville's Thermo-12 is one product

 

[MikeHalloran]

Look for "marine exhaust" companies. They can fabricate insulated exhaust pipes with a hardshell coating, or fabric- faced blankets.



Mike Halloran
Pembroke Pines, FL, USA

 

[kenvlach]

Instead of insulation, use a perforated stainless steel tube for shielding, with at least a 1" air gap around the exhaust pipe.

 

[PEDARRIN2]

Thanks for the replies.

What makes this job difficult is the diesel engine is below grade and the exhaust has to pass through occupied space.

It is a renovation of a school where we are installing sprinklers and a fire pump. There was no room to put the pump in a separate building and not any room to put it on the ground floor. We are putting it and a water storage tank under a new classroom addition. I am not so concerned about the piping in the pump room but am concerned about the temperature of the piping as it passes through the occupied first floor and exits out the roof.

I will probably specify 2" calcium silicate with an aluminum jacket, which is what my HVAC counterpart recommended.

 

[MikeHalloran]

An engine's vibration will turn that stuff to powder pretty quickly, unless you provide some isolation, e.g. two lined bellows and a short intermediate pipe in the engineroom.



Mike Halloran
Pembroke Pines, FL, USA