Sticking grain all over again

"One of our customers is a municipal water and sewerage services. One day this customer contacted us because they had a recurring problem that was putting a lot of strain on staff and machinery in the company."

Alois Bäuml, field representative for basic material screens at HEIN, LEHMANN, listened attentively to the customer's description. This customer reported on the use of his street sweeping machines - and the problem that regularly occurred after street cleaning.

"To get leaves and other debris out of street gutters, the street sweepers drive their brushes very close to the curb. This would normally raise a lot of dust. But so that the machines don't keep dusting entire streets, water is added to the sweepings during the process."

So far so good. But now comes the crux of the matter, because afterwards the waste has to be separated from the water and sand again. However, this did not work at all well for our customer, as Alois Bäuml could see from pictures and videos that the customer has made.

"The screening machine was equipped with a simple type of a press welded grid. The customer complained about the transport of the sweepings mixture onto the vibrating grid as well as the many plugged grains. The grid became so clogged after only a few tipping processes that a lot of sand and sometimes also water did not go through the openings, but was simply transported to the discharge side."

After analysing the photos and videos, the disadvantages of the machine used were obvious - and of course the right solution: our modern WS 85® system.

"The vibrating chute that the customer had used before was too small and actually not suitable for the process. The loading process was also not optimised, because all the sweepings were not tipped out of the truck evenly, but in gushes. With the WS 85® system and a few adjustments, it ran like clockwork."

Replacing the machine with our modern exchange system did not immediately bring the expected result. But when the pure plastic sieves were replaced by welded slotted sieves cast in plastic, the separation process was really impressive.

"The advantages were already obvious during the first tipping processes - the material was no longer simply lying on the screen deck and building up to cause sticking grain. It rather slid nicely over the deck. We even had to slow down the sliding process by using several slats in the transverse directions."

A great relief, but by no means the only one. Due to the problems mentioned above, the customer had to clean the old machine frequently and at great expense. To do so, the grille had always to be removed completely, along with the sieve box and sieve frame.

"Today, our customer will probably hardly ever have to clean the screen. But if he does, then the next advantage is just around the corner: the entire screen box no longer has to be removed. The customer only needs to replace the affected screen panels and can then clean the removed screen panel in peace and without much stress."

The customer's enthusiasm came promptly. Thanks to all the advantages that the WS 85® system brought him, the machine downtime was also reduced many times over.

"To date, our customer is more than satisfied. Only recently we received an e-mail in which he wrote that he had never experienced a screen performing so impeccably over such a long period of time. There is hardly anything that pleases and motivates us more than receiving feedback like this."

The problem with the sweepers had developed into a real HEIN, LEHMANN success story: Today, our customer's sweepers clean the streets with water as before. Afterwards, however, the WS 85® system ensures optimal drainage of the sweepings. A real happy ending!


Do you also have a challenge and need a partner who has the best solutions at the ready? Contact us - we will be happy to advise you.