Lamellas for Scheur suction cleaning machines

Vibraplast AG provides for string-free results.

When working with scrubber-driers, the cleaning result depends on various factors. Have the right brushes or pads been selected for the type of soiling and the floor covering? Is the cleaning agent used correct and has it been dosed correctly? The speed of work and the amount of cleaning solution also have an influence on the cleaning result. However, the cleaning professional knows that the most important factor for a perfect end result is an optimally functioning suction nozzle with first-class suction blades. What at first glance looks like an ordinary piece of rubber or plastic to the layman is in many cases a piece of "hi-tech" from Aadorf in Switzerland.

Vibraplast AG, founded in 1961, has built up expertise in the field of rubber lamellas for the cleaning industry over the decades and is now one of the world's leading companies in this field. The most important international manufacturers of scrubber-driers are among the Aadorn-based company's customers. Around 40 employees work for the specialist, whose business areas also include noise protection, vibration isolation, foam technology, elastomer and plastics technology.

The company is a long-standing partner to the cleaning industry. Customers in Germany and abroad purchase components and complete assemblies for industrial cleaning machines. Customised solutions at every level of vertical integration are among the core competencies of this successful company.

The cleaning lamella

The successful cleaning of floor coverings ends with the complete collection of the loosened dirt particles. This is achieved with a vacuum suction nozzle fitted with appropriate cleaning lamellae. There are basically two different manufacturing processes. The stamping of moulded parts has become established. For cost reasons, injection moulded parts are also used in some cases. However, production below 70 Shore A is problematic. This process is therefore only used to a limited extent. Vibraplast AG is able to offer both variants to the highest quality standards. Years of experience in the cleaning industry have shown that individual parameters (e.g. hardness) should not be considered in isolation.

A large number of supporting properties make up a high-quality slat:

Sliding friction coefficient
Rebound resilience
Microbe resistance
Ozone resistance
Abrasion properties
Tilt angle
Oil and alkali resistance
Lubricating properties
Thickness tolerance
Shore A hardness

Selection criteria for the practice

On our specially developed lamella test bench, we simulate the use of different cleaning lamellas on a wide variety of floor coverings.

The adjustment of the suction nozzle depends on the one hand on the manufacturer and on the other hand on the intended use. Basically, the contact pressure can be differentiated by height-adjustable support wheels or by the suction nozzle's own weight. Some machine manufacturers also work with additional weights to increase the lamella pressure. If the cleaning results are uneven, check the setting of the suction nozzle. Before making any changes, make sure that the lamella is not too worn and/or the suction nozzle is not damaged.

The correct height setting is achieved when the wiper edge of the rear blade rests across the entire width of the suction nozzle. The optimum angle of inclination is 45 degrees to the floor covering. A very important factor is the perfect slat cutting edge - without interruptions or damage. The appropriate lamella combination must be selected depending on the surface condition, the amount of water and the oil and grease content of the dirt. The selected hardness has a decisive influence on the ability to adapt to unevenness. Information on this can be found in the manufacturer's operating manual.

Vibraplast AG is certified in accordance with ISO 9001:2000 and is able to maintain the tightest tolerances thanks to state-of-the-art measuring equipment in order to guarantee consistent quality and fulfilment of customer requirements together with the machine manufacturer.

Polyurethan PUR

The base material for cleaning lamellas consists of polyurethanes (PU, DIN abbreviation: PUR). However, the designation is only of a general nature (analogous to wood, steel or rubber) and says little about the technical properties.

Polyurethanes are plastics or synthetic resins that result from the polyaddition reaction of diols or polyols with polyisocyanates. Depending on the manufacturing process, the material can be hard and brittle or soft and elastic. Elastomers in particular have a comparatively high tensile strength. In foamed form, polyurethane is known as permanently elastic soft foam (e.g. for sports shoe soles) or as hard assembly foam. Polyurethanes can have different properties depending on the choice of isocyanate and polyol. The density of unfoamed polyurethane varies between around 1000 and 1250 kg/m³. The subsequent properties are essentially determined by the polyol component.

To achieve the desired properties, it is not usually the isocyanate component that is adjusted, but the polyol component (chemically modified). Therefore, cleaning lamellae may only be compared for quality comparison if the identical raw material mixture is taken into account. Otherwise there is a risk of comparing "apples with pears". The manufacturing costs are significantly dependent on the additives used. However, exact mix specifications are rarely available.

Test specifications

Polyurethanes can be tested relatively easily.

An unknown material can be identified or characterised using thermal or FTIR analysis. However, as measuring devices are often lacking in practice, the incoming goods inspection is limited to measuring the thickness (mm) and hardness (Shore A). Although these test parameters are very important for the successful use of a cleaning lamella, they are not the only decisive factors.

Long-term tests have shown that special attention must be paid to microbe protection and resistance to acids and oil. The reliability and service life of cleaning lamellae are largely dependent on the raw material and the corresponding additives. Optically flawless materials deform and break down after a short period of use and are no longer suitable for cleaning. Cracks or deformations mean that collected dirty water cannot be fully absorbed. The result is false air and the resulting water and dirt residues. The cleaning result is unsatisfactory.

Scraper geometry

One of the main prerequisites for the proper functioning of a cleaning lamella is the correct contact pressure and angle of attack. These are determined by the design of the cleaning machine. Optimum deformation results in a negative pressure (vacuum). The air flow sucks the dirt into the dirty water tank. A rebound elasticity corresponding to the floor compensates for unevenness in different floor conditions.

Another factor influencing an optimum cleaning result is the correct selection of the appropriate louvre combinations. The front and rear slats must be matched to each other. The front blade should collect the dirty water and guide it to the suction nozzle. The rear slat must be absolutely tight to ensure that the floor covering is dry after cleaning.