Reel mileage calculation based on Diameter of reel
Reel mileage calculation based on Diameter of reel
Hai .. this is Guhan from Kochi- India, I like to share this calculation worksheet -Reel mileage based on diameter of reel.
How do we calculate Reel mileage?
Reel mileage = Total No. of pages / Net Reel weight eg. 1384000 pg / 5522 kg = 250.63 pg/kg (or) 23.81 sqm/kg
Here getting number of pages from production is easy, but net reel weight ? we waste some length in web lead,cut waste, core end paper waste etc..collecting such data is one side, production started with balance reel and end with same or another reel !! How do we calculate correct net reel weight?
We have tried with Excel work sheet for solving this problem (image attached) by converting diameter of reels to reel net weight. By this diameter calculation method we can find mileage for - a single production or even a day production
Getting accurate diameter data of reels used and balance reels are consider for reel mileage.
Now Reel mileage = Total No of Pages / (Net reel wt + O/bal. Reel wt - C/bal Reel wt) ;
Reel weight are converted from diameter data by formula. In this image below i have entered a day usage for example, full consumed reel in O/bal side and this is used to calculate net weight (full consumption). Retained balance reel has to be entered in C/bal side for deduction of reel weight from full consumption. Or else if you have net reel weight you can eliminate full reel diameter in O/b side.
We know "No production will make with one complete reel" , so production may start with old reel with one diameter and end with another. We know every gram of paper we spent is accountable for mileage.
Reel mileage is computed as Pages per Kg of Newsprint (or) Sq.meter of paper per Kg finally.
For example ;
Page size 546 x 348 (mm) = 0.19 sq.m
If we get 251 pages/kg then (251 / 2 * 0.19) convert to sheet and multiply with page size in sq.m we get 23.845 sq.m/kg , then how to check my mileage?
by using formula convert - 1000 / 23.845 gives your 41.937 GSM or 42 GSM of paper simply.
What pages / Kg if I print with 42.5 GSM will be ?
Pages/Kg = (1000 / GSM) / page size (sq.m) * 2
let us try - (1000 / 42.5) / 0.19 *2 = 247.7 Pages / kg
(1000 / 42) / 0.19 *2 = 250.6 Pages / kg
Now you can alter the page size or GSM and calculate pages / kg at any time.
Attachment:
Reel mileage image and pdf file.
For more details please visit my post - https://sites.google.com/view/guhansk/newsprint-reel/newsprint-mileage
Have a good day..
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Thank you
Regards
Guhan S K
Printer,
guhgee.sk@gmail.com
https://sites.google.com/view/guhansk
In addition to Reel mileage here I am posting this worksheet on Paper caliper calculation.
When paper caliper down ▼ we get more copies by physical count, and if paper caliper is up ▲ we get less copies. This phenomenon clearly give that paper caliper is most important criteria. Paper manufacture maintain their standard average GSM mostly but customer satisfaction also important, 64 ʮm caliper and 55 ʮm caliper gives different amount of copies, so mostly they compromised to give high yield of production.
How to find Caliper?
First fill basic data like machine cut-off, machine speed, Reel width etc.. then you have to record diameter change at fixed interval (lap time in second) of every 10 mm for example with same machine speed. After recording diameter of reel (keep minimum 5+ entry) you will get average readings graph of Caliper. If your data entry is wrong then chart shows abnormality.