50 years of block technology – looking back and looking ahead to the future

 In 1975, Hermann Kronseder tackled an idea he had been pondering for some time: mechanically interlinked machines, preferably without free container movement on conveyor belts. A single block, in which starwheels or feed screws pass bottles individually from one machine to the next. It was a revolutionary concept in the beverage machinery sector because, back then, nearly all of the machines in a filling line were set up at considerable distances from each other. Only the filler and the closer formed a single unit at the time. The machines were connected by way of long stretches of conveyor belts, with accumulation tables preventing stoppages from affecting the entire line. A certain minimum level of such buffering was needed in order to ensure a line’s efficiency. Or rather, that was the conventional thinking at the time. 

But Hermann Kronseder wanted to do away with as many accumulation areas as possible. In Europe in the 1970s, beverages were filled almost exclusively into glass bottles. When these bottles run up against each other on the accumulation table, they generate a lot of noise. And bottles are liable to burst, fall over or jam under the pressure of backed up bottles, which in turn results in downtimes. Hermann Kronseder figured that around 80 per cent of all issues and downtimes impacting a line’s efficiency could be attributed to too-generously dimensioned accumulation areas. He added to the calculation the conveyors’ enormous requirements for space, operating personnel and energy as well as the initial cost. He was convinced that there had to be a more elegant solution. He thought, “If a machine is repeatedly having the same error, I don’t need to build a longer accumulation area. What I need is to analyse and fix the cause of the error at the design level.” His logic went as follows: Once we’ve managed to get the machine to run virtually without errors, then we can synchronise it with other machines in a block, with no accumulation areas needed.

“Easier said than done,” said Matthias Wahl, who now heads up the company’s patents department, during an interview for this article. He recalls how Hermann Kronseder once told him how it all began while the two were on a business trip together: “He’d been considering the idea for some time already, but in the early days the technology necessary for putting it into practice simply didn’t exist. Into the 1960s, you often had to install two or even three labellers downstream of a fast filler in order to achieve a desired line output. Labellers often caused more disruptions than fillers did back then. But when Krones brought an extremely reliable high-speed labelling station to market in the early 1970s, a single labeller was enough to keep up with even the fastest filler – and so the block was technically possible for the first time.” Another difficulty back then was the drive technology: The mechanically linked machines in a block are run by a central drive and so they operate at exactly the same speed. The electronic controls and frequency converters for infinitely adjustable three-phase motors that are common today and make it possible to control each machine’s speed individually were prohibitively expensive then. 

The block revolutionises the industry 

In the early 1970s, Hermann Kronseder was quite alone in his idea. Nobody believed that it could work. But he stuck with it. A new occupational safety regulation on noise abatement entering into force in Germany in 1974 gave him the nudge he needed to make the quieter block a reality, especially since Krones was, as of that very year, now making its own filling and closing machines. In the end, he was able to persuade a brewery to test his prototype. In 1975, the very first “Krones BLOC”, comprising a filler, closer and labeller, went into operation at a brewery in the Upper Palatinate region – and it immediately increased the efficiency of the filling from 75 to 97 per cent. It was a resounding success and marked the birth of a technology that would not only revolutionise the industry but has continued to shape it to this day.  

“Hermann Kronseder and his team were able to get a handle on the various issues plaguing the individual machines and then synchronised them into a block that yielded real benefits for the brewery,” says Franz Obermeier, who heads up the filling technology division at Krones and whose work has touched on block technology, among other things, for many years now. “And we continue to do just that to this day. We’re getting higher and higher performance from the concept and integrating functions and systems in a way that generates real added value for our customers. Puzzling out a block design is just plain fun.”

Krones continues to design new blocks

Krones didn’t stop with the filler-labeller block of 1975. On the contrary, for the past 50 years, the company has regularly churned out new block solutions (see timeline at the end of this article). The exacting concept has demanded a great deal of innovation, then and now. The second-generation block integrated an empty-bottle inspector – which brought with it the risk of decreased performance because too many bottles rejected due to poor quality would mean gaps in the line and, ultimately, underutilisation of filler capacity. “For that reason, Krones decided in 1977 to pursue a new idea: electronic block-synchronisation. The inspector would be equipped with its own infinitely adjustable drive so that it would simply run faster if the reject rate was high,” explains Matthias Wahl. The “SynchroBloc” connected the inspector and filler electronically, but the downstream closer and labeller were still linked mechanically. 

Noise protection was once again the cornerstone for the next stage of development, recalls Wahl: “Because Krones already had the block in its portfolio, we received a grant from Germany’s Federal Ministry of Education and Research in 1982 to develop a low-noise filling line.” In this project, Krones built a really fast SuperBLOC comprising an inspector, filler, closer and labeller, with quiet solutions for transport, infeed and onward transport of the bottles outside the block. “Really fast” back in 1983 meant 60,000 bottles per hour. This line was Krones’ breakthrough. It was installed in a Munich brewery that was wanting to speed up their filling operation but lacked the space for a conventional line – a classic case for the SuperBLOC. During the Interbrau trade fair in 1985, Krones invited customers to visit the brewery and see the technology in action. “There were often more prospective customers in the bottling hall there than we had at the fair itself,” wrote Hermann Kronseder in his memoirs. Krones continued to steadily improve the SuperBLOC, which initially was reserved largely for glass bottles. At the 1993 drinktec, Krones unveiled the SuperBLOC in V layout, the so called V-BLOC, the first block to feature touch-screen controls.

A block for every container type

In 1988, Krones began expanding its container portfolio and in 1992 developed a filler-seamer block for cans. In it, can lids were sterilised using steam and placed on the cans in the filler discharge area. The lids were closed immediately after, in a seamer carousel. Krones began offering the canning block as the Modulfill Bloc FS-C, which incorporates Krones’ own Modulseam can seamer, in 2017 and then in 2020 added the option of isolator technology for sensitive beverages.  

Likewise at the end of the 1980s, PET bottles had come onto the scene and spurred Krones to develop the first of a series of dedicated block solutions: In 1988, Krones presented a precursor to what would eventually become the Contiform Bloc, though this version still incorporated air conveyors between the blow moulder and the filler. Because the soft surface of PET bottles makes them particularly susceptible to scuffing – meaning scratch rings caused by the bottles rubbing against each other or guide elements during transport – Krones began work in 1995 to develop a new neck handling system that used controllable clamps. These hold the bottles by the neck ring, so they travel suspended, with no contact to other bottles or machine parts. One thing that makes this new technology extra special is that the neck ring of a PET bottle remains at the same level as it moves through the rinser, filler and capper, regardless of the dimensions of the respective bottle. As a result, there is no need to change over the top part of each machine to accommodate varying bottle heights. In 1997, Krones presented to the public a PET SuperBLOC comprising a rinser, filler, capper and labeller – fitted with the new neck handling system.  

After the introduction of the first Krones stretch blow moulder in 1997 came the Contiform Bloc for filling still beverages in 1999 – in the form we still know today, with a blow moulder, filler, and capper. An option for carbonated beverages included an integrated rinser. That was followed soon after by a version designed specially for still water and juices, in which the blow moulder and filler were intentionally set at a distance from each other for microbiological reasons. The individual bottles are transferred through an airlock by way of a linear conveyor – a toothed belt with neck grippers. As a result, the filler can be cleaned using foam without impacting the blow moulder at all.  

Milestones for PET 

In response to the rapid advance of plastic bottles in the markets, Krones churned out a series of new solutions in quick succession. With the PET-Asept system, Krones created a block that consisted of an injector, rinser and filler in a cleanroom, specially for filling microbiologically sensitive beverages under sterile conditions. Here, too, the blow moulder stood at a distance from the cleanroom portion of the system, and was connected to it by a linear conveyor with neck grippers. In 2005, this concept was exhibited at a trade fair, though instead of a linear conveyor it used a chain with neck grippers, which made for a dynamic bottle buffer offsetting temporary differences in speed or brief interruptions between the blow moulder and the downstream part of the line.  

Once the revised Contiroll HS became available, delivering a labeller with end-to-end neck handling, the plan was to build a concept incorporating a dynamic bottle buffer for a layout that placed the labeller downstream of the blow moulder (or the buffer, as the case may be). But it ultimately worked out somewhat differently: Krones developed a high-precision drive concept that made it possible to drive each of the machines in the block to be precisely matched to the other machines. “Even during start-up and shut-down,” points out Matthias Wahl: “And so, the dynamic bottle buffer was no longer necessary.”

The result of this and numerous other innovations came in 2009: the ErgoBloc L, the first of its kind worldwide. What made this block extra special was that it integrated not only the stretch blow moulder, labeller, filler and capper into a single block but that it did so in a new order: The freshly blow-moulded bottles – dry and free of dust – were now labelled prior to filling. This development demanded innovation because the empty, thin-walled PET bottles don’t provide sufficient counterpressure on their own for labelling. “So, we recycle the last pressure stage of the blow moulder and use it to inflate the PET bottles,” explains Matthias Wahl. “That is the core of our block thinking: We make intelligent use of resources that are already available and thus keep costs low. Each individual step may seem small, but the sum of those steps is what makes Krones block technology successful,” he says. “It took countless individual development steps to get the ErgoBloc L to work the way it does today.”  

Other advantageous details – besides the fully synchronised individual electric drives for the starwheels and machines, which obviated the need for the dynamic bottle buffer – include electronically controlled “gap skip” where there’s a missing or ejected bottle. Previously, filling, labelling and capping at subsequent machines continued despite the missing bottle. Now, an electronic signal tells the machine to skip the gap, which saves on labels, adhesives, product and caps. Additional examples include the integration of existing modules such as the Multireel magazine for label or sleeve reels, which significantly reduced the time and effort involved for operators, and a fully automatic robot for changing over the moulds, which was first introduced in 2017. Thus, the ErgoBloc L has, over time, evolved into a highly efficient and economical system with low operator involvement that produces and processes extremely lightweight, thin-walled bottles at high speeds. Particularly in the area of water bottling, the ErgoBloc L has set a high standard for the market. 

That is the core of our block thinking: We use resources that are already available intelligently and thus keep costs low. Each individual step may seem small, but the sum of those steps is what makes Krones block technology successful. Matthias WahlHead of the patents department

In 2013, the Contipure AseptBloc made a complete, aseptically safe process chain shopfloor reality. Today, Krones offers block solutions for PET as an individually configurable modular system for nearly every wet-end job: that is stretch blow moulding, filling and capping, labelling, and even chemical or physical sterilisation of PET preforms if needed. And that’s not all: Dry-end operations – that is, packer and palletiser – can also be synchronised in a block.  

Linking all of the functions of the wet end and the dry end would come very close to fulfilling Hermann Kronseder’s dream of moving bottles through the line without contact. But we’re not there just yet. “The wet end processes individual bottles at high speeds in a continuous flow. The dry end, on the other hand, is not continuous. Certain segments operate intermittently, processing bottles and packs in batches. This transition still requires a bit of buffer in the production process,” explains Franz Obermeier: “We have a solution for that, which makes it possible to go from single-lane to multiple-lane container flow with no bottle pressure and at the same time to achieve the buffering function of earlier conveyor solutions on a minimised footprint.”  

The future looks bright for the block 

Are there limits to what can be “blocked”? “Technically, no,” says Obermeier, “but the block also has to make financial sense. If one of the component parts has a stoppage, then the entire block comes to a standstill.” For Obermeier, there is no better example of Krones’ innovative power than the block. “We are still well ahead of the competition in this area, in part because we can tap into the wealth of experience that comes from half a century of development plus our expertise on each of the individual machines. Every day, we find something new that we can integrate into the block to benefit our customers – which nobody else can quickly copy. That is truly a unique selling point for Krones.” And so, we’re far from reaching the end of the block’s development. You see, as Matthias Wahl points out, “We’re still always striving to achieve Hermann Kronseder’s dream of contactless bottle transport, from the start of the line to its end.” 

For me, there is no better example of Krones’ innovative power than the block. Still today, we are pulling more and more performance from the concept and integrating functions and systems that create added value for our customers. Franz ObermeierHead of filling technology