Insulations jackets on shell of furnace
Insulations jackets on shell of furnace
(OP)
Hi!.
My name is henrique and i´m from Brazil. We work on melting aluminium industry and we would like to Know if it possible put insulations cover jacket on shell of us melting furnace. We have some doubt about dilatation of shell and ceramic insulation inside of the furnace.Our furnace has 1045 steel on shell.
Following information.
working temperature about 1100ºc inside of furnace. On roof area.
Shell temperatures closer 180ºc
I would like to put 1" of jacket insulation´s to achieve temperatures closer 85ºc
First all i need to know some informations ,about dilatation of shell and work temperature of the refractories inside of furnace. Is it possible some damage for furnace?
Henrique B Matos
My name is henrique and i´m from Brazil. We work on melting aluminium industry and we would like to Know if it possible put insulations cover jacket on shell of us melting furnace. We have some doubt about dilatation of shell and ceramic insulation inside of the furnace.Our furnace has 1045 steel on shell.
Following information.
working temperature about 1100ºc inside of furnace. On roof area.
Shell temperatures closer 180ºc
I would like to put 1" of jacket insulation´s to achieve temperatures closer 85ºc
First all i need to know some informations ,about dilatation of shell and work temperature of the refractories inside of furnace. Is it possible some damage for furnace?
Henrique B Matos





RE: Insulations jackets on shell of furnace
And what value of thermal conductivity is your insulation? One inch might be a bit light.
TTFN
FAQ731-376: Eng-Tips.com Forum Policies
RE: Insulations jackets on shell of furnace
at:
100ºC 0,03 w/mºC
150ºC 0,05 w/mºC
200ºc 0,07 w/mºC
250ºc 0,08 w/mºc
300º 0,09 w/mºc
I don´t put insulation yet. I would like to Know if it possible same damages for my furnace.
Diameter of furnace is 2,4 meter at 180ºc.If i put that jacket the temperatures is gonna higher,but how much? and dilatation? 350 mm of Refractories castables inside of furnace.
RE: Insulations jackets on shell of furnace
And that's my point, 0.03 W/m-K is essentially air; most insulator run in the 0.05 to 0.1 range
Why is the temperature changing? The heat input remains the same, so the heat flux is the same, so the temperature drop is the same.
TTFN
FAQ731-376: Eng-Tips.com Forum Policies
RE: Insulations jackets on shell of furnace
RE: Insulations jackets on shell of furnace
sorry. I has that datasheet only on portugues.
RE: Insulations jackets on shell of furnace
We have two cases where we use an air gap with an insulated a metal shield to give contact surface below 50°C. The hot side skin temperature is around 200°C.
RE: Insulations jackets on shell of furnace
RE: Insulations jackets on shell of furnace
you are dealing with multilayer wall. Each layer has got its own thermal resistance (characterized by thermal conductivity and thickness). The thermal resistances are in series (electric analogy) and to get the overall thermal resistance of the multilayer wall you have to sum up the thermal resistance of each layer. Each layer you add acts as a barrier to the heat flux.
RE: Insulations jackets on shell of furnace
RE: Insulations jackets on shell of furnace
Hoping to say Tata
RE: Insulations jackets on shell of furnace
Mike Halloran
Pembroke Pines, FL, USA
RE: Insulations jackets on shell of furnace
I make it like you wrote and your post and i´m found 140ºc.I think i gonna put another values until the result match.
By the way, I don´t have afraid of the temperatures of steel shell. I have afraid if diference of dilatation between the shell and ceramics castables.
thank´s
RE: Insulations jackets on shell of furnace
As far as the dilatation, or expansion of the ceramic castable, then a thermal blanket will tend to cushion the expansion of the castable. Reducing the shell temperature will be a secondary effect. Calculating the stresses in the outer shell due to the thermal expansion of the castable is a little difficult unless you know the temperature dependent properties of the castable. I have seen a simpler method used in american Ladle design standards but you still need to know the elastic modulus of the materials.
Hoping to say Tata