Screw (Spiral) Washers

Screw / Auger or spiral washers are highly efficient machines designed to remove clay, silt, and other undesirable materials from crushed or natural sand and aggregates, particularly those in the 0-7 mm size range. Removing these harmful substances, which directly impact aggregate quality in concrete and asphalt production, is critical to the durability and performance of the final product.

Working Principle: Intense Friction and Classification

The operating principle of Screw / Auger washers is based on the combination of water and mechanical action:

• The material is fed into an inclined trough along with water. The spiral blades inside the trough rotate at a slow speed, constantly mixing and rubbing the material together.
• This intense friction movement allows substances such as clay and silt that are stuck to the surface of the material grains to dissolve and mix with the water.
• As the screw rotates, the heavier, cleaned sand grains are carried upwards along the trough. Some of the water is filtered back, dewatering the material.
• Dirty water and the fine particles (slime) suspended in it are thrown out through the weirs located at the bottom of the vessel.
• The cleaned and moisture-reduced final product is transferred from the discharge chute at the top of the vessel to the stock area or to the next process.

These washers, which can be produced with single or double screws to meet different capacity needs, stand out with their high efficiency.

Durability and Efficiency

The screw blades, manufactured from high-quality sheet steel, are lined with replaceable rubber liners to increase wear resistance and reduce maintenance costs. This design extends equipment life and simplifies maintenance. Designed for high-capacity operations, screw washers minimize leakage, ensuring maximum efficiency, especially when washing materials that require intensive cleaning and contain high levels of contamination.