Monthly Bag Closing Thread Requirement Calculator
Fill in how many bags you close in a day, a week or a month, and get what to order for the month — cones, kilometres of thread, and how long a single cone lasts on your line.
- Bags per month
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- Thread per month
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- Cones per day
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- Hours per cone
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What this calculator does
It turns your input into a bag closing thread order: the kilometres your line will use in a month, the cones to buy, and how long one cone lasts before a changeover. Everything starts from the distance the sewing head travels across the mouth of the bag, and the rest is arithmetic on that.
Every figure comes back as a range because the chain-off tail your machine leaves at each end of a seam varies. The consumption figures behind it are Mahalaxmi Thread production data from real bag closing lines, not garment tables — those assume around 18 stitches per inch on thin fabric, nothing like a bag closer running an 8–10 mm stitch through woven PP. Cones are always rounded up, and the headline order quantity uses the top of the range, so you cannot under-order by following it.
How to use it
Enter the bag mouth width, in inches, mm or cm, and pick the chain your closer runs. Then give your output as bags per day, per week or per month — choose per day if your line does not run every day, and set your own working days. Safety stock and second seams for FIBC sit under More options.
Formulas
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thread per bag = bag mouth width × chain consumption × seamsChain consumption is a multiple of the bag width, set by whether you run a single, double or quad chain. It already includes normal sewing wastage. -
bags per month = bags per day × working daysA weekly figure is taken over seven days and a monthly one over 30. Per day uses the working days you enter. -
thread per month = bags per month × thread per bagShown in kilometres, since a month of bag closing runs to hundreds of them. -
cones to order = ceiling(thread per month ÷ cone length)Rounded up, because a part cone is not something you can order. -
hours per cone = (cone length ÷ thread per bag) ÷ bags per day × 8How long one cone lasts, on an eight hour shift day.
Examples
A packing line closing 8,000 fertilizer sacks a day, 26 working days, 24 in mouth, double chain, from 5,000 m cones:
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8,000 × 26 → 208,000 bags a monthThe same line entered as 200,000 per month, or 46,667 per week, lands in the same place. -
208,000 bags → 317 – 349 km of threadAt 1.52 – 1.68 m a bag for a 24 in double chain closure. -
317 – 349 km ÷ 5,000 m → 64 – 70 conesOrder against 70. Six cones is a cheaper mistake than a line standing idle. -
3 cones a day, about 3 hrs a coneThree changeovers in every eight hour shift. On 25,000 m jumbo cones the same line gets roughly fifteen hours from a cone — one change every two shifts. That is usually where the larger cone starts paying for itself.
Frequently asked questions
How many cones should I actually order?
Order against the higher end of the range. The calculator gives a range because chain-off tail varies from machine to machine, and the cost of ordering one cone too many is far lower than the cost of a line standing idle. The primary figure at the top of the results panel is already rounded up.
Should I add a wastage percentage?
No. Normal sewing wastage is already inside the consumption figure. The safety stock field under More options is for something different — cover against demand swings and delivery lead time. Leave it at zero if you order to a fixed schedule.
What does hours per cone tell me?
It estimates how long one cone lasts at your stated output, assuming an eight hour shift. It is the number that decides whether a larger cone is worth it: if you are changing cones twice a shift, the changeover time and the risk of a mid-bag run-out usually justify moving up a cone size.
Does this work for FIBC and jumbo bags?
Yes, with one change. FIBC and sacks stitched at both ends need Seams stitched per bag set to 2 under More options. Loop attachment and cross reinforcement seams are additional and are not covered here — send us the bag drawing and we will work those out with you.
Why do you ask for cone length in metres rather than weight?
Because metres are exact. Length per kilogram varies with count, ply and finish, so working back from cone weight would put an unknown error into every result. If your cones are labelled by weight, ask us for the metres on your specific ticket.
Threads for your schedule
Spun Polyester Bag Closing Thread is the workhorse for FIBC, feed, fertilizer and cement sacks, while Polypropylene Bag Closing Thread suits high-speed lines and bulk agro and mineral packaging. Both are covered in our bag closing and packaging thread range.
Related calculators
- Sewing Thread Count Converter Ne, Tex, dtex, denier, metres per kg and yards per lb, in both directions and ply-aware.
- Bags Per Cone Calculator for Bag Closing Thread How many bags one cone will close, and the cones a run of 10,000, 1 lakh or 5 lakh bags needs.
- Spun Polyester to Polypropylene Thread Converter The equivalent bag closing thread in the other range, either direction, matched on strength or thickness.
- Bag Closing Needle Size Calculator The needle range published for a given bag closing thread, or every bag closing thread that runs on the needle already in your machine.
Want us to hold stock against your schedule?
Send us your monthly volume and bag size and we will plan cone sizes and delivery around your production, so you are not ordering in a hurry. Talk to our technical team.