Author Topic: Conveyor temp fluctuation  (Read 2366 times)

Offline Denis Kolar

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Conveyor temp fluctuation
« on: July 08, 2011, 07:45:56 AM »
I ran some shirts last night and I decided to temp check almost every shirt that comes out of the dryer.
With the same belt speed and the same temp setting I was getting reading between 315 and 355.
Could that be because my temp controller is allowing the heat to drop down by as much as 25 degrees from a set temp?

Also, I have noticed that the temp varies from shirt to shirt. I ran Sanmar's PC61 both in regular and women cut. Ones that are women cut were coming out with lower temp reading than a regular cut PC61.

Another question about conveyor. Would it be OK if I close openings for an exhaust fans on a top of the dryer and build a hood that I would install on the top of the dryers end opening? It seams that the exhaust fans draw the heat out of the dryer.

In the end, I decided to measure the time shirt is in the heat chamber, from entering to exiting the dyer. It measured 1 minute and 10 seconds. I have the heat set to 465 degrees wit the thermocouple being right under the panels (not at the shirt level).

I think this is enough rambling for one post :)

Thanks in advance


Offline whitewater

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Re: Conveyor temp fluctuation
« Reply #1 on: July 08, 2011, 08:48:11 AM »
you would like the shirt to be under the dryer for about a minute, so that speed is great. I let the shirts I do get to about 385, but no more than 400, and seems to work well.

Someone else can chime in here, maybe I am thinking the larger shirt soaks (not correct word) up more of the heat in turns makes it hotter, more surface area..where the girls shirts there is more space around it so not so much heat bouncing off from it.  I do adjust the dryer settings for each type of garment. And adjust the settings for each season, actually everyday its different! LOL!

My father in law made a hood like you want to do..he has it over his vaster dryer. It would be another variable to watch out for, but probably a good idea then you won't be breathing in smoke from the shirts...


Offline mk162

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Re: Conveyor temp fluctuation
« Reply #2 on: July 08, 2011, 08:56:17 AM »
electric panels cycle on and off, this is the nature of the beast.  Also, the pc61 is thicker than the lpc61, so that will vary the temp as well.  a lot of it also has to do with moisture content of the shirts.  more water equals more steam which equals less heat to the shirts.

try increasing your temp and speed, see if that helps.

Offline RICK STEFANICK

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Re: Conveyor temp fluctuation
« Reply #3 on: July 09, 2011, 08:45:11 PM »
what kind of device were you checking the temps with.  strips will vary 10-15, the little grey lazer guns the same ?  just curious? 
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Offline Sbrem

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Re: Conveyor temp fluctuation
« Reply #4 on: July 09, 2011, 10:21:12 PM »
If it's an all electric dryer, if you have a percentage input timer, you have wider temp swings because it shuts on and off depending on the amount of time you have it set to. For instance, if it has a 30 second cycle, and you have it at 80%, that means that it's cooling down 20% of the time.  If you can get a better controller with a thermocouple to read the temperature, it will run more consistently. We have an older dryer like this, and we cut the timer out all together and simply vary the belt speed. Just a thought.

Steve
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Offline Denis Kolar

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Re: Conveyor temp fluctuation
« Reply #5 on: July 11, 2011, 07:41:22 AM »
I check the temps with Temp gun.
Steve, the dryer has a temp controller and thermocouple.
After some playing with the settings, I got it to work. I ran a few test shirts with different mesh counts and different whites.
What was bizarre, I had one shirt printed with two different whites (Should have same cure temp and they are for the same purpose LB) and I placed it right in the middle so the ink has the same temp through the whole dryer.......... one was cured and one was NOT. WTF. Temp reading was 350 at my temp gun.