This unique concept, invented and patented by GIRON in 1997, is an innovative and exclusive solution for certain screening issues:
- Increasing the longevity of your steel cloths by maintaining your permeability
- Improving the performance of your polyurethane cloths
- Optimising the evacuation of wash water on a fitted polyurethane screen
- Twice the permeability of your polyurethane systems
- Eight times the longevity of your conventional steel facilities
These cloths may be equipped with hooks (lateral or longitudinal tension), mounted on frames or manufactured in the form of modules. They are a very efficient way to replace your traditional equipment, serving no real anti-clogging purpose.
To be tensioned, these cloths are made with tension hooks. These are steel sheets bent at an angle adapted to the different screens. The hooks are connected to the plastic screening surface by incorporating rectilinear profiles in the bending of sheets.
To use a cloth, this must be properly tensioned. Also, it must follow a curve defined by the screen manufacturers. The thicker the cloth, the more pronounced the curve to obtain good support. To ensure better positioning of the cloth on the frame, solid areas are provided on the cloth at each transverse support.
Square meshes :
- Rectangular meshes : 4 mm ≤ W ≤ 28 mm
- Profiles : 3×6 / 3.5×8 / 4×11 / 6×13
- Possible options : Overlap bibs, reinforcements on the supports, holes for central fixing, etc.
The origin of Polymixte
In the area of screening surfaces, the fight against wear has always been a major concern. Several solutions to wear problems have emerged, including the move from steel to polyurethane which is probably the most significant event in recent years.
A screening surface, whether metal or plastic, is essentially defined by its mesh, a hole framed by the material with the primary purpose of ensuring the passage of a maximum amount of material of a desired particle size cut.
The choice of the material impacts the expected results depending on whether priority is given to wear or abrasion resistance, that is to say, the durability of the screen or, conversely, if permeability is preferred, the volume of production per tonne produced per hour.
If a highly rigid material such as high resistance steel is chosen, just add a little between each hole to ensure sufficient mechanical strength of the screen. If, instead, a more flexible material such as rubber or polyurethane is chosen, more material is needed to maintain the size of the mesh.
The coated steel wire of a wear-resistant synthetic material has been known for years as a potentially worthwhile solution. The GIRON company took an interest in it back in the early 80s. If the round section of composite wire has become the natural choice as the logical continuation of traditional steel wire, the identification of active parameters and their systematic and exclusive optimisation in terms of abrasion resistance, permeability and mechanical strength has enabled us to achieve a hybrid screening surface.
The principles of Polymixte were therefore established: :
- polyurethane (A) in the upper part and thick enough to ensure a good impact resistance and good resistance to abrasion
- a rectangular steel frame (B) in the lower part to optimise the vertical stiffness and mechanically support the load of the products
- a limited lower layer (C1) because not subject to abrasion
- a reduced lateral layer (C2) to maximise permeability
- resulting in a hybrid composite profile with trapezoidal section to facilitate the flow of the material and limit pegging.