Some technical info about machines
TISSUE PAPER CONVERTING MACHINES AND PACKAGING MACHINESBy “tissue and paper converting machinery” we call all the range of machines which, starting from a parent reel of soft tissue or paper, give finished items such as toilet paper rolls, kitchen towels, handkerchieves, table napkins, handtowels (rolled or folded or interfolded) and industrial towels (big towel rolls for working applications) also called JRT.
These machines have deep differences: you may find some almost manual ones (they are very old machines) semi-automatic start-stop ones and full-automatic non-stop ones where all the process is managed by PLCs, servomotors and touch-screen panels, so workers just have to control the right work done by machines.
Also: changeovers take much less time and they are much more accurate.
TOILET PAPER AND KITCHEN TOWELS CONVERTING AND PACKAGING MACHINESTo convert parent rolls of tissue into finished/wrapped toilet rolls you can use:
- a simple converting line with semi-automatic rewinder.
- a huge, fast (100-150.000 rolls/8 hours – and more) and expensive full-automatic converting line which, buying a special device, can also manufacture the real “kitchen towel”.
- core winder : to make carton cores
- rewinder : you put the parent roll of tissue and machine unwinds it, makes perforation every 12 cm (adjustable lenght), embosses (optionally) the tissue, rewinds it on the core, cuts and tails the last sheet.
- logsaw : what you get from the rewinder is a log as wide as the mother roll. By the logsaw you cut it to the finished roll dimension (approx. 10 cm wide)
- wrapper: to pack together several rolls by plastic, starting from a reel of polyethylene or other thermo-sealable material
- (optional) bundler: to make big plastic sacs with several packets of toilet rolls inside
By this line you will not get the real “kitchen towel” because this item is composed by two ply of tissue separately embossed and laminated by glue. While the STOP phase of the start/stop cycle too much glue would be applied on a small portion of tissue, destroying it . This is why laminated towels are usually produced by a full-automatic non-stop rewinder.
(Lately, machinery manufacturers developed some devices to laminate tissue by start-stop process but those units are very expensive : when will you pay the investment since capacity of your start-stop line keeps being so low? )
In these non-stop lines (with automatic rewinder, so) all machines are bigger than in the semi-automatic line as they must work much faster and without any stop in process. In the line there is also a log-accumulator so, whenever you put a new parent roll in the unwinder, the rest of the line will keep working, cutting and packing logs stored in the log-accumulator.
For packing toilet paper rolls and kitchen towels most common automatic packaging machine unwind and cut from a reel a sheet of plastic film (PE or BOP etc.) and they wrap by it the wanted number of rolls.
Some market also asks for toilet paper rolls wrapped into pre-made bags: these wrapping machinery are quite different from other ones.
“Reel to packet” wrappers have a 2-3-4 lines feeding section and they can make many different packet-configurations.
Altough last-generation of toilet paper packaging machines can do all possible packet-configurations (and changeover is possible just pushing a button or a touch-screen panel) we divide machines for “flat packets” (rolls are placed in standing position) from wrapping machines for laying position (rolls get into the wrapper and they become wrapped in the same position they have coming out from the log-saw).
Many models may also pack rolls on two layers: they get the first quantity (layer) of toilet paper rolls, they elevate them, they put the second quantity of rolls under first ones, then they wrap all rolls together.
Very often this kind of wrapper is completed by a suitable handle-applicator.
TISSUE AND PAPER NAPKINS CONVERTING MACHINESThere are two kinds of machinery to produce tissue paper napkins:
- converting machines which fold paper napkins by vacuum (sometimes there are some folding clamps on the folding cilynder as well).
- converting machines which make tissue napkins by a folding head composed by a couple of rotating steel cylinders with folding clamps. We call them “mechanical folders”.
This technology is applied on 1-line and 2-lines folders even if – for example – the machinery OMET model NIAGARA is a 4-lines folder.
Speed of vacuum system machinery is definitely lower, but there are vacuum folders up to 8 ways of production therefore, at the end, the daily production may be not a problem anyway.
During last period, many steps were done not only to improve the capacity of napkins machinery, but even to get a better quality in printing and something new in embossing: you may find napkins converting machines with flexographic printing stations up to 8 colors (central drum) and with embossing + glue-lamination unit which gives to paper napkins higher softness , bulk and quality.
Nowadays, an automatic transfer from the napkins folding machine to the automatic packaging machine is a must: such as an high quantity of converting tissue napkins per minute would oblige to employ too many workers for transferring napkins by hand.
CHANGEOVERS IN A NAPKINS CONVERTING LINEChangeover in a mechanical napkins folder takes at least two-three hours.
This is the real time you lose each time you replace folding head, embossing rollers, cliché cylinders and for doing all necessary adjustments (also with a waste of material, in consequence of it) plus another 30-60 minutes to replace size-parts of the napkins packaging machine.
Napkins folding machines which work by vacuum process are “multi-size” machines : by some simple adjustment you may convert napkins of all sizes between a range .
Unfortunately, one-line vacuum folders run up to 300-350 m/min while a mechanical folder runs up to 700 m/min.
Furthermore, you will have to replace edge embossing rollers and printing cylinders anyway, if you change napkin size.
You may easily understand which a vacuum folder is good for some application but not necessarily it solves matters of frequent changeovers.
Considering that, when daily capacity is an issue, the best choice is to use a napkins converting line (specially if the folder is mechanical-type) for one item only.
Obviously, not all converters have got so many lines, thus there is no choice than using a converting line for more than one napkins-size and packet-configuration.
Apart obvious advices like : schedule your job and do changeovers once per week, it is definitely better not to charge a napkins converting line by so many different folding heads, embossers, subjects to print, number of napkins to pack or the real capacity of that line will fell down dramatically.
If you have no choice, try at least to do it on a vacuum-type folder since in this machine changeover takes much less time.
Some other valid ideas are:
- add to the folder one or two additional embossing stations: in this way you don’t need to continuously remove embossing rollers but you will just pass the tissue from one or another embossing unit
- if you print many subjects in small quantities: buy a folder with 4 or 6 color units and always keep red ink in one unit, green ink in another unit, yellow, blue and so on in other units. In this way you will still have to replace clichés but you will have not to wash units to remove previous ink each time
- last but not least: modern packaging machines are servo-based: by operator panel you may adjust almost all parameters of your packer, cutting in this way the changeover requested time.
TISSUE HANDKERCHIEVES CONVERTING MACHINESAlthough some manufacturer offers hanky machines which mechanically fold the tissue (they are a sort of small napkins folders, at the end) if you want to get a good or high capacity (from 150 to 6-800 packets per minute) you need a vacuum hanky folder.
This kind of hanky machinery folds tissue by more lines at the same time. Sometimes they also add a perfume station.
After embossing + folding + cutting process, another station of the machine collects every single hanky in stacks and sends them to the packaging.
Then the first packer wraps them up into pocket packets (8-9-10 hankies in a packet) and cuts the plastic film for the re-closable opening (+self-adhesive label)…
Another over-wrapping machine will take a group of pocket packets and will wrap them in a same plastic bag for retail.