The rescheduled edition of RUBBERCON 2015, held on March 1-3, 2016 at Chennai was well-organized by IRI (Indian Rubber Institute) and IRCO (International Rubber Conference Organization).

Personally, this has been one of the best attended, well-organized and amongst biggest conferences I have been to recently. And to most delegates, this has been a different experience altogether.

Kudos to the complete team of organizing committee and supporting members for their massive efforts and time invested to make this conference a success. Because of them, I think RUBBERCON 2015 Chennai would easily occupy its unique place of prominence amongst biggest international conferences.

Over 75 speakers from 19 countries presented papers.

I was fortunate to successfully attend all my shortlisted speakers.

In an earlier post on mixing, I had mentioned that Single-stage mixing is not always cheaper and two-stage mixing is not always better. So, when my good friend, Dirk G.H. Reurslag, Sales Director (Industrial Solutions) of VMI Group (innovative leaders in rubber and tyre machinery) presented a new alternative on Continuous Final Mixing, it caught my attention quickly.

If you are looking to operate the complete mixing line by a single person, then you will find this JIT (Just in Time) approach to continuous mixing and blending of final rubber compounds interesting.

Before you get excited and review it’s long list of advantages, let me brief you the basic concept.

Basic Concept:

At its heart, this “mixing approach” has a cold-feed extruder along with the gear pump and they are controlled by software. VMI calls it iCOM®.

Sound’s simple (Right?)…. Wait. There’s more to it.

Operating Principle:

If you are seeking continuous proportional blending, you will know that proper distribution-mixing should take in the screw extruder.  And for final mixing, you require the screw extruder to properly incorporate the chemicals into the compound mix. Hence, the mixing screw design from VMI is advanced and unique.

The software used is equally sophisticated to control the speeds of the screw, the pump (and input pressure) and the volumetrically operated loss-in-weight feeding system.  The mixing and proportional blending uses

1. the volumetric operating principle of the gear pump (Read our earlier post on the concept of gear pump working) and
2. the abilities of homogeneous plasticizing of the rubber by the screw type extruder.

The special screw extruders are the VMI SHARK® extruder gear pump combinations. Different screw types are available. VMI recommends that they select a screw for you depending on your specific application.

The chemicals to be mixed are usually polymer bound, pre-dispersed, in the form of granules and are fed to the mixing extruder by an accurate volumetrically operated loss-in-weight feeding system.

For Proportional Blending, you require another side-feeding extruder gear-pump. The function of the screw of this side feeding extruder is not to mix. Rather, it only needs to properly plasticize the rubber and feed it (free of entrapped air) to the gear pump. The gear pump, in its turn, pumps the rubber compound into main mixing extruder in a volumetrically controlled fashion.

Continuous Final Mixing:  You can adopt this volumetric controlled mixing-extrusion in combination with accurate dosing of granules (that contains vulcanizing agent and accelerators) by a loss-in-weight feeder, to do continuous mixing.

Controlled Back and Forward Blending:  This is the third type of blending you could achieve in the extruder screw and barrel combination. This ‘compensates’ for little irregularities, if they might occur, in the loss in weight feeding of your polymer bound chemicals

VMI develops new concepts and innovative uses of technology with the end-user. VMI seeks to work with clients that will become launch users and close collaborators. In this way, VMI only ever takes to market concepts that have been tested under real-world conditions and proven to deliver competitive advantage.

Emphasizes Dirk Reurslag, “iCOM® solution is the more economical alternative to mixing in an internal mixer”. 

VMI worked out the iCOM® final mixing process, which includes the VMI SHARK continuous mixing solution in combination with Rhein Chemie’s  Rhenogran polymer bound chemicals and Rhein Chemie’s Rhenowave in-line analytics.

Benefits

Your advantages of VMI iCOM® for final mixing are

1. Lower investment on a final mix line delivering faster ROI and time to profit.
2. Compact, integrated solution occupying modest footprint.
3. Lower energy consumption as compared to the use of an internal mixer based final mixing line.
4. No electricity consumption peaks like in the case of an internal mixer. Hence, a sustainable solution that reduces energy use and improves profit potential.
5. Decentralized final mixing: This means Just in Time production as it reduces costly transport requirements for final batches. This reduces your stock of compounds and simplifies your logistics.
6. Just in time (decentralized) final mixing allows more ‘rapid’ vulcanizers, resulting in shorter vulcanizing time.
7. The proportional blending capabilities gives you various kinds of possibilities – Cross Blending (Most of you in mixing would know it well. This is referred to as just blending from two stage mixing), Controlled back and forward blending or Proportional Blending (both mentioned earlier.)
8. No ‘fading’ in the produced strip: no difference in heat treatment: With batch production the first part of the (long) strip was shorter on the mill than the last part.
9. Consistent quality of final mix compound with no scrap or rejects.
10. One Energy Cycle (Heat-up, Cool-down cycle) can be avoided by combining final mixing with first extrusion step.
11. Straining in the iCOM® line is possible
12. Degassing in the iCOM® line is possible
13. Affordable for even smaller companies

And just in case you thought this is an entirely new concept, you are in for a surprise. A Belgian compound manufacturer has the VMI iCOM® production line installed and successfully working since 2012.

VMI Group’s leadership in Extruder-Gear Pump solutions is renowned. They specialize in designing and engineering superior customized machinery for the rubber and tyre industry.

When I visited their stall at RUBBERCON 2015, I also learnt something new in their souvenir they were gifting to their customers. Known as Klomp, (more interesting facts here – Clogs), they are a type of footwear made in part or completely from wood. Pair of these is known as Klompen.

If you had been to their stall, did you pick up Klomp or Klompen (Single or Pair)?

Summarizing, if you are looking for an innovative, automatic, decentralized, Just-In-Time, final rubber mixing line without internal mixers, this new alternative in VMI iCOM® I learnt at RUBBERCON 2015 Chennai is worth your evaluation. I am also informed, it further enables production of customized, creative and precisely targeted compounds.             

What do you think?

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