When Jaap Nonhebel joined Geha Laverman in 2006, he had already had a long multi-faceted career in the food industry. Started as a cook but the engineering of catering machines very soon got his interest.
With a chef, the only thing that matters is what goes on the plate. Perfection! When it comes to sifting technique, Jaap at Geha Laverman is a master chef. The only thing that counts is the end product. That is what you are judged on.
Jaap enjoys being at the sieving machine. 'Sieving works slightly differently with every customer. The machines and sieving decks do not differ much. The way sieving is done is often part of the corporate culture. Every customer you go to has a different approach and you learn a lot that way.' Jaap has the strength and patience to hear the whole story - how they have solved problems in the past. Helps solve persistent problems.
Coincidence - is it a coincidence? -wants it, that Jaap has a lot of customers with screening installations. Seeing where things go wrong, but also seeing where things could be even better.
once in the processing hall, I actually saw immediately what was going on: three drop points through which the product fell straight up through a mesh
Where does it mostly go wrong? 'Wrong sieving or wrong sieving! For example, I recently visited a customer who had too many long sections in his finished product. He wanted to switch to a three-dimensional deck requested from us. Once in the processing hall, I actually saw immediately what was wrong: three drop points that made the product fall straight up through a mesh. The product actually never really lay flat on the screen. These problem points were quickly adjusted. And with success, problems were a thing of the past. Just a matter of tuning and adjusting the machine. Because of this advice, I did miss out on a good order - it was unnecessary and would have been a bad investment for the customer. That was something to swallow!
'Also, screening is often done too small. The screening decks then clog up very quickly. That will never work. Choosing spring steel when you really should go for stainless steel! Spring steel rusts, making it more rigid, which encourages clogging.
If you want to sieve very small, your material must be either bone-dry or thoroughly wet, otherwise you are guaranteed to have problems. Many problems can be solved by switching to a different type of wire sieve and if you want to be able to separate several products over the same sieve, the plastic Clip-Tec system is often a good solution because, due to a wide range of different versions, it adapts very well to the product.
'Then a creeping culprit: lack of maintenance. Some machines are so caked up that they almost collapse under their own weight. On other machines, the aggressiveness has disappeared because the springs are long overdue for replacement.
'Back to screen decks. What remains most important is the mesh size. The smaller you screen the smaller is your production capacity. If something is allowed to be 26 mm you don't go with mesh size 25 mm. Constant feedback on the composition of your end product ensures that you can make the right choice regarding your sieve deck and get the most out of your production.
'Sometimes there are other factors at play. For instance, some customers switch to PU for the sake of noise level. PU screens are so much quieter than steel ones. Provided the capacity of your screening plant allows it, you can switch from steel to PU without any problem. But even if that is not the case, sometimes a small loss of capacity is chosen, think of the mobile installation in a residential area.
Not infrequently, Jaap goes to work with a CAD programme to come up with a sieve layout that really matters: always with the quality of the end product and production capacity in mind. Perhaps this is where the obsessiveness that comes naturally to a chef reveals itself. After all, today's best result can be even better tomorrow.
