Heating of Industrial Machine

[leeekim]

I am looking ways to heat the rolls on a roll forming machine similar to this one.

The rolls of this machine are forming sheet metal with a painted surface. Because of the lack of heaters in the plant, to temperature can dip to 40F. We are told to maintain 70F to prevent cracking of the painted surface. The machine we have is about 20 feet in long 104 inches wide. We have brainstormed using forced air and radiant heat. What are your thoughts? Thanks!

 

[EdStainless]

I would go radiant, either IR or just use quartz lamps.
How are you going to keep the coil or steel warm? It needs a box with a small heater also.

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P.E. Metallurgy, Plymouth Tube

 

[MikeHalloran]

Put the supply of rolls and the roll forming machine in an insulated room.
Nothing fancy, just a frame building with normal house insulation,
and simple airlock vestibules for incoming rolls and outgoing product.
Provide the room with a household heating or heat/AC system, and enough makeup air and exhaust air to deal with heat from the motor(s) and lighting.
Easier and cheaper than trying to control the temperature of just the strip in a big building with the usual random drafts and rearrangements, mostly because the massive rolls will stabilize near the big building's air temperature, and transfer that into the strip.











Mike Halloran
Pembroke Pines, FL, USA

 

[chicopee]

or build a Lexan casing the over the entire length of the frame and connect ducts over the top of the casing for hot air supply.

 

[dvd]

What temperature is the painted sheet metal going to be when the workshop is 40F?

To warm the sheet and forming rolls to 70F from 40F may take a lot more wattage than suspected.

How many pounds per hour of sheet is run? How wide of a strip of material needs to be at 70F? How many pounds per hour of heated strip is this?

The formed areas of the sheet will have to be at 70F prior to contact with the forming rolls.

 

[EdStainless]

I like Mikes idea of just building a room around it. Keep it heated, block drafts, and store the coils in there as well.

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P.E. Metallurgy, Plymouth Tube

 

[leeekim]

The steel .014" thick precut and is preheated to 70F during the colder temps. Dimensions are about 190" x 22". However, it would have to travel about 20' at 300 fpm to our machine. I have a feeling it would have cooled down by the time it gets to our machine for forming. I would say the strip needs the heat 8" in from both ends.

I like the idea of building a room around the machine, however, I don't know how to estimate a cost of one. Does anyone have a quick guideline for it? The budget for this isn't the greatest.

I started with the idea of encasing the machine with Lexan, just thinking it might not be the most friendly for the maintenance guys.

I never had to do it before, but does anyone know what would be the cost of energy for using radiant heat vs hot air in an enclosed space?

Thanks for the input so far.

 

[chicopee]

Other than finding out from your insurance fire and property carrier, I am not sure where you can get that information altho., I am sure some construction organization have similar estimates; insurance companies have estimate on the cost per square foot depending on the type of construction such as fire resistive, light non-combustible, wood frame etc...Talk to your insurance agent as he or she will be able to help you.

 

[racookpe1978]

1. Reduce the losses when the plates are in the rollers.
As stated, lexan (clear plastic open-ended light weight frame around the roller machine.)

Don't get fancy: be able to lift it from your overhead crane as one piece, move it out of the way for access and maintenance, then lift back into position.
2. 190 x 22 is not very large. I'm going to assume the plates enter at one end, pass through (1 or more times ?) then exit the other end. If they exit the same end they enter, close off that end.
3. Monitor temperature - at the plate level!!, not above or below - in the entry, middle (on top), middle (below the plate), and end .
3. If the plate is substantially below 70 deg F, add a radiant heater at the entry (10% point), 1/4 point, 2/3 point, and exit (if back and forth process. If a once-through process, then BEFORE the entry at -25%, BEFORE the entry at -10%, AT the entry at +5%, then at 20%, 40%, and 60% points through the rollers.
4. Radiant heaters aimed "up" at the bottom of the plate between the rollers will be more efficient than heaters trying to "aim down" onto the plate. They will (over time) tend to heat the rollers up through the day, so the rollers, instead of being a heat sink for the plate, will be heated by the mechanical work of being pressed and by the rollers themselves. The trapped air below the lexan cover and walls will (over time) work to keep the plates from cooling.
5. The heaters need to be thermostat controlled, and timer controlled to begin heating before the work day starts.


But don't try to think to much. There are too many unknowns. It's still early November, you have several weeks to test several solutions, and no single solution needs to work perfectly. Just be better than nothing, and always better than the previous attempt.

 

[MikeHalloran]

First, talk to your maintenance people and the machine manufacturer about how much room they'll need around the machine, to change rolls and such, and how they'll lift the rolls and shafts, i.e. portable gantry within, or removable roof to allow use of the factory lifting equipment.

Then you can sketch out a building outline plan and elevations to get started.






Mike Halloran
Pembroke Pines, FL, USA