Pressure Screen Drum

A pressure screen drum – also referred to as a pressure screen cylinder or screen basket – is a cylindrical screening component installed inside a pressure screen housing. The drum is manufactured from V-shaped stainless steel profile wires resistance-welded to a grid of longitudinal support rods. The drum operates under positive pressure, with the slurry or pulp suspension flowing through the wedge wire slots. Acceptable fibers or particles pass through the slots while rejects are retained on the screen surface and discharged separately. The all-welded construction provides high mechanical strength, enabling the drum to withstand differential pressure without deforming or failing.

The V-shaped slot geometry ensures consistent screening performance. The slots are narrow on the outside surface and wider internally, preventing particles from becoming wedged and blocking the flow. This design maintains high screening efficiency over long operating periods. Slot openings range from 0.08 mm to 1.0 mm, with common applications using 0.10 mm to 0.35 mm for fine screening. Slot tolerance is held to ±0.02 mm to ±0.04 mm. The open area typically ranges from 25% to 45%, providing good throughput while maintaining separation precision. The continuous slot construction provides maximum open area, optimizing screening efficiency and reducing pressure drop across the drum.

The screen drum is constructed with profile wires on the outside surface and support rods on the inside. The profile wires and support rods are welded at every intersection. For high-pressure applications, additional support rods are added and circumferential stiffener rings are used to prevent the drum from collapsing under pressure. Profile wire sizes commonly used include 1×2 mm, 1.5×3 mm, and 2×4 mm. The drum is manufactured with flanged ends or plain ends depending on the equipment design. Materials include stainless steel 304 and 316L, with 2205 duplex steel available for more demanding applications. The drum can also be supplied with a hard chrome coating for improved wear resistance.