Flip-Flow Screen

Flip-Flow Screen — An Anti-Blinding Screen That “Breathes”

Core idea in one sentence: The screen surface itself expands and contracts — elastic screen panels are continuously tensioned and relaxed by the counter-rotating motion of two screen decks, generating accelerations of 30–50 g that fluff up and toss sticky, wet materials, eliminating screen blinding at the source.

Basic profile

表格

Dimension	Description
Positioning	A dry-type screening machine designed specifically for “hard-to-screen” materials: wet, sticky, easily blinding, or high-fiber feed
Core principle	Dual-mass system (fixed screen frame + floating screen frame) moving in opposite directions drives elastic polyurethane screen panels through periodic tension/relaxation (flip-flop motion), so the apertures “breathe” open and closed
Key parameters	Screen acceleration 30–50 g; flip-flop frequency ≈ 800 cycles/min; dry classification down to 3 mm; screen amplitude 40–50 mm
vs. conventional screens	A conventional screen has a rigid fixed surface that cakes up with wet material; a flip-flow screen actively deforms its surface, self-cleans, and resists sticking and blinding
Main applications	Municipal solid waste / aged waste sorting, construction & demolition waste, coal washing (raw coal, lignite, coal slime, coke), metallurgy & building materials, slag, bauxite, etc.

How the “flip-flop” works (two states per half cycle)

State A — Surface tensioned: The fixed and floating frames move apart in opposite directions; adjacent crossbeams reach maximum spacing and the elastic screen is pulled flat, apertures open wide.
State B — Surface relaxed (half cycle later): The two frames move toward each other; the beam spacing shrinks and the elastic screen sags into waves; the sudden deformation tosses and loosens the material so fines pass through.

The two frames run 180° out of phase, so the screen surface flexes back and forth at roughly 800 times per minute.

Key performance figures

30–50 g — screen surface acceleration (peak ≈ 50 g)
≈ 800 cycles/min — tension–relaxation frequency
Down to 3 mm — dry classification cut size
40–50 mm — large screen amplitude
180° — phase difference between the inner and outer frames

vs. conventional vibrating screen

表格

Conventional screen	Flip-flow screen
Rigid fixed surface	Elastic polyurethane panels that actively flex
Wet/sticky feed cakes and blinds the mesh	Self-cleaning, no sticking, no blinding
Lower acceleration	30–50 g acceleration, small screen area achieves high efficiency
Best for clean, dry, free-flowing material	Best for wet, sticky, high-fiber, fine materials; lower noise and dynamic load

Typical applications

Municipal solid waste / aged waste sorting
C&D / renovation waste de-slagging and classification
Deep screening of raw coal, lignite, coal slime, coke
Slag, bauxite
Compost, topsoil, reclaimed asphalt (mobile tracked units)
Industries covered: solid waste, coal, power, metallurgy, building materials, mining

Three points worth remembering

Why it outperforms conventional screens: A regular screen has a rigid surface — wet fines cake onto it and blind the apertures. The flip-flow screen hangs its panels between a fixed crossbeam and a floating crossbeam; the two frames move 180° out of phase, forcing the panels through repeated tension–relaxation so the apertures “breathe.” Sticky material is thrown off by high-frequency acceleration — this is active anti-blinding, not rinsing or shutdown-and-cleaning.
Selection caveat: Flip-flow screens shine on wet, sticky, high-fiber feeds. If the material is clean and dry, a conventional vibrating screen is usually more economical; also factor in elastic panel life and replacement cost in the operating budget.
Role on waste-sorting lines: It typically works alongside trommel screens — the trommel does coarse classification, and the flip-flow screen handles the wet, sticky fines section (manufacturers cite recycling rates over 92% for mixed plastics and paper, with pre-removal of fines by the flip-flow screen being a key step).