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Does anyone remember the takt time formula for the reflow oven

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#54002

Does anyone remember the takt time formula for the reflow oven | 12 March, 2008

Takt time and the relationship with the conveyor speed and oven length.

Thanks much!!!

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#54004

Does anyone remember the takt time formula for the reflow oven | 12 March, 2008

Not so sure takt time is an appropriate for measure to assess a single process, like a reflow oven. Look here: http://www.google.com/search?sourceid=navclient&ie=UTF-8&rls=GGLC,GGLC:1969-53,GGLC:en&q=takt+time+formula+

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#54008

Does anyone remember the takt time formula for the reflow oven | 13 March, 2008

Takt time (without a google search) is the rate (amount of time per pc.) at which stuff gets made on an assembly line, a workcell, a hi-speed SMT line, CNC machine cell, etc.... Takt time is governed by the gate (the slowest person, machine, etc. in your workcell).

A reflow oven has no stops - it is a continuous process where you can shove boards in there literally back-to-back (not recommended, but do-able).

I guess if you really wanted to get technical, you can go back to your 6th grade algerbra class, and use the distance formula D=vt...That way, you can derive a time, based on the total travel length of the oven and conveyor speed. So, for example, 1 board by itself on a 12 ft. oven, and a conveyor speed of 36"/min. (3FPM) would take t=d/v= 12/3 =4 min. or 240 seconds...that is not takt time, though, 'cause your oven isn't "fully loaded."

To get a takt time, the assembly line (or oven) has to be "wet" (fully loaded), and you'll have to assume that boards are coming into your oven at a consistent rate, and they're being spaced apart consistently. Now, you've got your "oven takt time" (ie a PCB will come out every X number of minutes or seconds)... So, for example, say your oven is fully loaded, and you're running at 3 FPM (36"/ min.). Say your boards are spaced 5" apart ALL THE TIME. T=5/36=0.138 min. = 8.33 seconds. So, you'll have a board come out every 8.3 seconds. Again, to get accurate numbers, there's lots of assumptions here, and you'd have to be working in this manufacturing "utopia" where people are loading boards at a consistent rate, and consistent spacing..

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#54038

Does anyone remember the takt time formula for the reflow oven | 14 March, 2008

If it works on paper, it has to work in the real world.

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#54048

Does anyone remember the takt time formula for the reflow oven | 14 March, 2008

KRIKIES Hillbilly!

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#54202

Does anyone remember the takt time formula for the reflow oven | 27 March, 2008

If you get into a discussion with a Lean guy/gal, takt will be the rate of customer demand. People often use takt & cycle time synonymously...FWIW

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#54218

Does anyone remember the takt time formula for the reflow oven | 31 March, 2008

Assuming the following:

L=Process Length of the oven t=Desired profile time in mins(depends on the paste/glue used) l=PCB length l1=gap between consecutive PCBs

Then the total no. of PCBs per hour is"

(L*60/t)/(l+l1)

Vinit

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#54355

Does anyone remember the takt time formula for the reflow oven | 11 April, 2008

Tak time is depend on the solder paste requirement all solder paste there are deferent tak time.

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#54365

Does anyone remember the takt time formula for the reflow oven | 11 April, 2008

How do you assure your operator follows this math? Our operators can't even pull their pants all the way up or wear their hats on straight.

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#54366

Does anyone remember the takt time formula for the reflow oven | 11 April, 2008

KRIKIES! I wonder if people can find "dee lees common dee-nomb-me-nay-tor."

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Reflow Oven