New high-performance preform feed from KHS: Feedflow

Frank Haesendonckx*
Dieter Holler**

With the new Feedflow preform feed unit KHS now provides optimum handling and a reliable flow of lightweight preforms to the infeed star on the InnoPET Blomax stretch blow molder even at high performance rates. Compared to standard feed systems this innovative setup is distinguished by extremely gentle and active preform conveying, coupled with very good access.  The optimized installation concept requires very little space and provides great ease of operation and maintenance, fast changeovers and a high degree of flexibility. 

Output of up to 84,000 preforms per hour

On the Feedflow preform feed unit up to 84,000 preforms per hour can be conveyed, with reliable high-speed transportation also a given for ultralight preforms which weigh less than 10 g. Positioned directly upstream of the blow molder, the Feedflow horizontal  conveyor now complements KHS' established Feedmax preform sorter and feed system. 

Feedmax conveys preforms from the silo to the stretch blow molder

Preforms for blow molding are usually taken from their transport packaging to the preform silo by a fork-lift truck with a tilter. A fill level monitor makes sure that the tilter replenishes the silo automatically  and an optional silo lid protects the preforms from foreign objects. For very sensitive products that have a higher hygiene requirement the Feedmax system can also be fully enclosed, helping to perfectly protect the product at this initial stage in the bottling process. 

*Manager of Sales and Technology, KHS Corpoplast GmbH, Hamburg, Germany. 

   Phone: +49 40 67907 475

**Design Engineering, KHS Corpoplast GmbH, Hamburg, Germany. 

   Phone: +49 40 67907 9522

From the silo the preforms travel along an inclined conveyor to an interim conveyor which discharges into the preform sorter. This comprises two parallel rollers arranged at specified intervals to one another which travel in opposite directions, so that the preforms are correctly aligned without being damaged. At the end of the sorter the preforms are then fed in one lane to a discharge rail or, depending on the application, onto the active, horizontal Feedflow conveying segment. 

Conveying methods

The traditional discharge rail makes use of the force of gravity to generate the required accumulation pressure which keeps the preforms continuously moving towards the stretch blow molder.  The preform weight, infeed angle, surface properties of the discharge rail, temperature and humidity are thus all factors which influence reliable transportation and conveying speed. This complexity can pose a risk to the course of production and line availability. Besides the aforementioned factors, fluctuations in preform quality can also cause disruption on the traditional discharge rail, resulting in the need for time-consuming adjustments. 

As opposed to the traditional infeed by discharge rail, the Feedflow method actively conveys the preforms along the horizontal feed segment in a targeted flow of air. The three sections on the Feedflow conveying segment each have blower motors which can be regulated and are equipped with prefilters. An optional model with sterile filters is also available. 

Intelligent speed control

The frequency-controlled blower motors on the Feedflow ensure a constant and reliable flow of materials to the blow molder at the necessary accumulation pressure. As the roller conveyor speed is automatically adjusted as the number of preforms in the feed track drops, a high permanent level of line availability is achieved.

Space requirements

Thanks to the application of the active preform conveying method, the new Feedmax system with its integrated Feedflow preform feed is much more compact in size, both in height and footprint.

Perfect access

Active preform conveying means that the working height of the feed unit can be much lower as there is no longer any need for a defined infeed angle on the feed track of around three meters. In other words, the system can dispense with its usual high platform. This greatly improves accessibility and also makes the machine much easier to operate and service. 

Shorter changeover times

Format changeovers required when a different preform design is scheduled are greatly simplified thanks to the Feedflow's automated recipe selection menu and much lower height. In many cases changeover times are therefore shorter. 

Of great interest to the industry – and not just for high-speed bottling

The Feedflow system may have been primarily developed for high-speed systems – and in particular for the smooth conveying of lightweight preforms on the same – yet its many benefits are also pertinent to lines which have a lower output.  Here, too, companies can profit from the fact that Feedflow also reliably processes very light preforms; even the tiniest reduction in preform weight, possible for a great number of products, gives bottlers considerable long-term reductions in cost. Reducing the preform weight by just one gram at a production of 100 million bottles per year, for example, can yield savings in material costs of approximately €140,000.  

Standard preform conveying segments can be converted

Companies who to date have conveyed their preforms to the stretch blow molder using the traditional method can convert and reap the many benefits of the innovative Feedmax system. All that needs to be done is to replace the discharge rail with a Feedflow system and a roller conveyor frame and to adjust the inclined conveyor. Existing silos with upstream box tilters can be integrated into the new conveying system.

KHS operating system

The combined Feedmax/Feedflow feed system has a controller included in the blow molder. This means that an extra operator panel is no longer required and all of the adjustable parameters can be regulated directly via the blow molder interface. The KHS ClearLine HMI, which has won a number of awards for its excellent ergonomics, logical navigation and attractive design, controls the process centrally, reduces machine complexity and makes operating the entire setup a much simpler affair. A touch panel ensures user-friendly machine operator prompting that employs colored graphics, easy-to-remember icons and interactive, self-explanatory handling instructions. These logical operator prompts provide access to varying degrees of viewing detail and different operating levels as the specific application requires.

Conclusion

To summarize, with its new Feedflow module KHS can now offer its customers gentle, fast and reliable conveying also of light and ultralight preforms to the stretch blow molder, thus promoting high levels of line efficiency. The many benefits this innovation contains include great ease of operation and maintenance, minimized space requirements, optimized format changeover times and added potential material and cost savings.