Packaging Coin Twist Tobacco Tins Part 2.

See here for part 1.

Animation of tobacco pressing cycle – courtesy of Lee’s Trading (Kunming) Co. Ltd – China

Tobacco Press
In the primary tobacco processing cycle, the world over, the tobacco baling press is a one vertical cylinder operation. The moisturised and still warm tobacco lamina (loose leaves without the stems) are conveyed to the press over a conveyor belt and dumped into the press chamber. Due to the absolute disoriented character of the tobacco leaves as the fall into the press chamber the pressing action in a single vertical movement is likely to result in an irregular consistency of the pressed tobacco. Or in other words the single press ram operating in only a downwards direction in the relatively narrow, but very high (5 to 7 metres) press chamber filled with the loosely dumped tobacco leaves results without any doubt in a rather uneven compression of the tobacco lamina. Which consequently results in several “loose” areas, particularly in the utmost bottom corners of the 100-200 kg. tobacco bale or even worse a too forcefully pressed top layer of the bale, giving problems in the secondary process step, when the bales are being disintegrated to feed the lamina into the slicers for the finished product machinery (cigarettes among others). This argument is clearly visible in the animation of the pressing cycle from Lee Trading.

Building extension for a one-direction vertical tobacco press – courtesy of Lee’s Trading (Kunming) Co. Ltd – China

Furthermore, an exorbitant large force must be exerted on the application of a single pressing ram to achieve a sufficient compression of the tobacco lamina in the press box. This large force in one direction enhances the risk of the disoriented tumbling tobacco leaves to break during the pressing cycle increasing the rust of tobacco dust. While it is well-known in the industry, that tobacco is very springy and the chance that the tobacco leaves spring back into the free area as soon as the vertical press ram is lifted back to its original resting position, is very much a possibility, which requires extra pressing time to “deadpan” the tobacco leaves. To make this pressing system more disadvantageous the construction of the exceptionally long hydraulic cylinder to operate in a 5 to 6 m. pressing chamber is very unfavourable, as it requires not only a huge steel platform around it but also the factory building to be some 13 m. high up in the air (as the image shows), which increases the building costs tremendously.

Drawing from patent JPS5341497A

To eliminate all these disadvantages of the existing and well-known tobacco presses I designed, developed and built for Société Nationale des Tabacs & Allumettes (SNTA), a two-step tobacco press (my patent: DE2738663A1 and JPS5341497A) in conjunction with an automatic tobacco lamina crate assembling and filling machine with conveyors, shaping block and pneumatically operated grippers preceding the filling and pressing station (my patent: DE2738664A1). Although the press pushed the tobacco lamina straight into the assembled 100 kg. wooden crates, similar to the idea for Theodorus Niemeyer to press the pipe tobacco straight into the rosette positioned in the bottom of the tin, the similarity stops there and consequently I will not describe the assembling of the wooden tobacco crates here.

Two-step tobacco press – drawing from patent DE2738663A1

Two-step tobacco press
In contrast to the universally implemented tobacco presses with one vertical pressing ram, my tobacco press uses a two-step operation, compressing the tobacco leaves successively by a horizontal and a vertical ram. The press chamber, in which both the horizontal and vertical compressing action is undertaken, is a rectangular parallel-epipedon from which the two side walls are stationary. The back wall is movable as part of the horizontal press ram, which after the horizontal movement forward transforms into the back wall of the vertical press chamber and the front wall, which functions as the stationary wall of the vertical press ram. The top is over a length of 2/3 of the pressing chamber open to allow the entry of the loose lamina from the weighing unit. The other 1/3 is the bottom plate of the vertical press ram.

In the old days tobacco was pressed like this

In contrast to the open top, the bottom of the press chamber is for 2/3 of its length closed and for 1/3 open to allow the vertical press ram to push the comprised tobacco into the under this opening positioned wooden tobacco shipping case. The dimensions of the vertical press ram are equal to those of the tobacco shipping case, so that the press can push the horizontally pre-compressed leaves straight into the shipping case. With both press rams in their rest positions the dimensions of the press chamber is large enough to receive the loosely dumped 100 kg tobacco lamina from the weighing scale positioned on top of the press chamber and fed by a conveyor belt, moving the leaves from the primary processing section of the plant. In addition to the quality of the compression by this two-step pressing device, the whole system has some other very significant advantages compared to the single vertical tobacco press.

The newly built SNTA factory in Algiers. You see on this building no extension in height for the tobacco press

As the image above here shows, the single vertical tobacco press needs a very high compressing chamber, some 5 to 6 metres, and consequently a hydraulic system with a cylinder of another 5 to 6 metres, resulting in a total construction height of some 12 metres and more with a very expensive hydraulic installation to operate it. This requires extra and very expensive building facilities as well as a huge steel construction to secure the operation. The exorbitant hydraulic force required for the vertical pressing of some 100 to 200 kg. loose tobacco leaves, requires a heavy-duty design of the foundation of the press. Remember action = reaction. When you push down with force you have to secure the steel construction on a frame/foundation, which can eliminate the pressing force (if not your press and steel construction is lifted from its feet). This is it. I hope I have clearly explained the operation procedure, as well as the typical advantages of the two-step tobacco press design. Anyway for Theodorus Niemeyer it was sufficient to invite me to consider a redesign in miniature for its 2-oz pipe tobacco tins Flying Dutchman.

Redesign in miniature
In the first part of this article I have already specified the various functions of the automatic packaging for the tobacco tin. Go there to refresh your memory, while here I will concentrate on the pressing cycle. You can argue that the extra costs for the heavy-duty steel construction, the exorbitant long hydraulic cylinder and the extra costs for the height of the building, have nothing to do with the 2-oz tobacco tin, but that’s not quite correct. Pipe tobacco is very springy and the volume of 2 oz (50 gr.) loose pipe tobacco is larger than the volume available by the rosette in its unfolded form. It requires a hydraulic cylinder with significant force to press the tobacco and keep it down into the tin, so that the packaging girl is able to situate the plastic film on top of it, fold the rosette and close the tin with the lid. It is quite a construction (action = reaction) and above all hydraulics are expensive.

Empty Flying Dutchman tin

The automatic line I built was fully pneumatic, including its controls. That means that the two-step tobacco press also was pneumatic, which made it much more cost effective and faster. The front of the horizontal press ram was a half-circle the size of the unfolded rosette in the tobacco tin. Remember after moving forward the front of the horizontal ram becomes the side wall of the vertical press ram. To complete the design the stationary back wall of the press chamber was designed as the other half of the circle, ending up as a full circle when the horizontal press ram was moved forward and the vertical ram moved consequently in a press chamber the size of the inner diameter of the unfolded rosette, pushing the pre-compressed tobacco straight into the rosette situated in the bottom of the tobacco tin. After placing the circular piece of plastic film on top of the compressed tobacco and folding the paper rosette, the top lid of the tobacco tin could be pressed on the bottom and the automatic operation was finished. It was quite a nice design and worked out perfectly.

Anton M. Steeman

Packaging Coin Twist Tobacco Tins Part 1.

Ton, the father of a good friend of mine

As I told in my Humble Beginnings part 1 blogpost one of my influences to start pipe-smoking is Ton, the father of a long time friend of mine. The last half year we spoke quite a lot with each other. We can get along great, I mean, he smokes pipe, I smoke pipe, he likes whisky, I like whisky. ‘Nuff said right? Ton is what I call an old school pipe-smoker. He smokes from just a couple of pipes until they are utterly used up to the point that he has to hold them together with duct tape. As far as tobacco goes he only smokes a couple of blends (preferably Amphora) and that’s it. So I helped him get some other pipes and pointed him towards the blends of Motzek, which have a good price/quality ratio. Ton is a retired packaging engineer so when the subject came up I asked what he had done in the past. To my surprise it turned out that he was one of the pioneers if not the pioneer in the automatization of the packaging of the (for us pipes-smokers) well known coin twist tobacco tin. So I asked him to write a guest-blog about this. Beware, it sometimes gets a bit technical but nonetheless it is a very interesting read!

Flying Dutchman

In the world of pipe tobacco the so called 50 gr. “coin twist tobacco tin” was (and still is) one of the most popular packages for pipe tobacco. One of the well-known brands in this category was Flying Dutchman, manufactured by the Dutch tobacco company Royal Theodorus Niemeyer Ltd. in Groningen, currently part of the multinational British American Tobacco (BAT). In that epoch, we talk about the 50’s and 60’s of the last century, the whole process of filling and packing the coin twist tin was a manual process. During the mid-70’s, when all types of industry were looking into automating manual production processes (particularly packaging consumer goods, as labour costs were increasing) Theodorus Niemeyer invited my engineering company (which specialised in packaging technology) to design and build an automatic packaging line for the Flying Dutchman 50 gr. coin twist tobacco tin.

Packing the old way in the 3 Nuns factory

The packaging line had the following operations to perform:

  • Picking a tin bottom from a large box in which they were freely stored and align it properly into the conveying system of the packaging line.
  • Separating one single paper rosette from a fiercely pressed stack of rosettes, (we used an air stream to separate the rosettes from each other) and place the rosette into the bottom of the tobacco tin.
  • The third step was the most important and complicated one. Weighing 50 gr. loose pipe tobacco and nicely press it into the rosette placed in the bottom of the tin in such a way that after pressing the rosette could be folded close, like flower petals close for the night. As said this was the most critical step as tobacco in general is very springy and tends to return to its original volume (which was larger than the volume of the unfolded rosette), consequently making it almost impossible to fold the rosette over the tobacco and close the tin.
  • In the manual operation the packaging girls could correct by holding the hand press down for a longer period and put the cap of the tobacco tin immediately on top of the bottom using the cap as second press to keep the springy tobacco under control.
  • As the automatic packaging line had to replace a row of packaging girls, we didn’t have the luxury to hold the pressed tobacco down for an extended time. And that brings us to our patented tobacco pressing system. More about that in a minute, as it’s the heart of the development and based on one of my patents.
  • The last steps of the automatic packaging line are the positioning of a thin circular piece of plastic film to cover the “open space” on top of the tobacco after the paper rosette is folded closed.
  • And finally the selection, aligning, positioning and pressing down of the lid of the tobacco tin.

Royal Theodorus Niemeyer tobacco factory in Groningen

It is important to keep in mind that it was the 70’s of last century and there were not yet available any electronic devices, no pc’s or plc’s, no computerised automatization. Everything had to be executed either pneumatically, mechanically or electrically by means of relays and similar devices. This made for huge and complicated control panels. I have a second observation to make. As I designed and built this Theodorus Niemeyer packaging line, as well as the two tobacco packaging lines on which this was based, some 50 years ago, I have unfortunately no technical drawings or photographs to show any more.

The invitation by Theodorus Niemeyer to design and build the tobacco packaging line had a prelude, as I had just finished a large project for the design and construction of two tobacco packaging lines for Société Nationale des Tabacs et Allumettes (SNTA) in Algeria. Although the Algerian tobacco lines were large installations for the leaves and stems tumbling out of the primary processing section and pressed and packaged in large 100 kg. wooden folding cases, Niemeyer obviously had the impression that the revolutionary pressing cycle I had developed for the Algerian lines could be built in miniature for their 50 gr. Flying Dutchman tobacco tins.

And that brings us to the heart of the problem of packaging loose tobacco. In other words I have to explain the special design of the press cycle for the Algerian lines to justify the reasoning that Theodorus Niemeyer thought a miniature design for the 50 gr. Flying Dutchman was feasible to solve its problem. I’m well aware that most readers of this blog have at least basic knowledge about processing tobacco, but it is essential for this article to know something about tobacco processing and consequently I take the liberty to include a section about this topic. Note: As I said before I have no photos, images or drawings of the original SNTA packaging lines I developed. It’s too long ago and by wandering throughout the world I lost all of my archives, documents and much more. To illustrate this article I use some images from Lee’s Trading (Kunming) Co. Ltd in China. I have no experience with this company, so don’t see it as an endorsement, there is no commercial interest involved from my side. The pictures are for illustration purposes only.

Tobacco Processing
Tobacco leaves undergo a number of processes before they finally become the finished product, as a cigarette, rolling tobacco, pipe tobacco or another tobacco product. Whilst there are commercial variations in tobacco processes, particularly in respect to the different consumer products, the basic process steps can be divided into two distinct phases:

  • Primary processing where tobacco stem is separated from the leaf (lamina) and both leaf and stem prepared to the stage at which it is ready for inclusion in the finished product.
  • Secondary processing includes forming the cigarettes, cigars, pipe tobacco or any other consumer product and packing.

Some factories at which tobacco materials are produced undertake both primary and secondary processing. Others undertake either one or the other alone, either sending the tobacco which has been subjected to primary processing elsewhere for secondary processing.

Tobacco lamina after threshing

And that was the situation in Algeria. The new to-be-built plant in Algiers, the capital of Algeria at the coast of the Mediterranean Sea, was a typical primary processing plant and distribution centre, supplying the pre-prepared and pressed tobacco in wooden boxes to the secondary processing plants (cigarettes) spread throughout the country, even in the far south halfway the Sahara desert (I had a beautiful trip to visit this plant going over the Atlas Mountains). The preliminary processing of tobacco involves curing the leaf (either by air, heat or sunlight) followed by threshing to separate the lamina and the stem. The tobacco is first subject to a conditioning process using steam to ensure that the tobacco is sufficiently pliable to allow the subsequent processing steps to be completed without damage to the material. In some circumstances additional materials may be added at this stage for flavouring the tobacco.

Horizontal threshing unit – photo courtesy of Lee’s Trading (Kunming) Co. Ltd – China

Although the composition of tobacco threshing and re-drying varies due to different factories, all threshing and re-drying lines include three basic procedures: threshing, lamina and stem re-drying and the pre-pressing and packaging procedure. The threshing unit is one of the key equipment in the primary process step and it has decisive effects on the quality of finished products. Precise separation and counter-flow winnowing ensure good lamina-stem separation results. Following the threshing cycle the loose and pre-processed lamina are conveyed to the pressing and packaging system, where the lamina with required moisture and temperature is pressed into shape, then packed and strapped in bales for easy storage and transportation. The system has a metering check weighing function.

See here for part 2: https://dutchpipesmoker.wordpress.com/2017/05/05/packaging-coin-twist-tobacco-tins-part-2/