Maintenance
Vibratory machines have few moving parts, but the parts they have are under constant load. The checks below keep the separation and the flow stable.
Screen panels
- Inspect for blinded openings; clean after each product change and at wash-down.
- Look for worn, torn or stretched openings. A changed opening changes the separation size.
- Check that the panel is tensioned or clamped evenly. A loose panel flaps and wears quickly.
Springs and mounts
- Check coil or leaf springs for cracks and for sagging. A broken spring changes the stroke on one side and twists the deck.
- Check rubber mounts and isolators for hardening and splits.
- Compare the stroke on both sides of the machine; a difference points to a spring or a loose mount.
Vibration motors
- Check the fastening bolts at every interval; the torque is specified by the motor maker.
- Listen for bearing noise and feel for excess heat. Bearings in vibration motors are a wear part and are replaced on condition or at the interval in the motor documentation.
- On two-motor machines, check that the unbalance weights are set identically and that the motors run counter to each other.
- Check cables and glands for chafing from the vibration.
Structure and fasteners
- Check all bolted joints. Vibration loosens fasteners; loose joints crack welds.
- Inspect welds at the deck supports and at the motor mounts for cracks.
- Check chutes and outlets for build-up, especially with sticky fruit.
Dewatering and aspiration units
- Empty and clean the water tray; check that the drain outlet is clear.
- On fan-assisted dryers and aspiration units, clean the fan and the duct; check filter or trap elements where fitted.
Cleaning
Stainless steel machines are washed down according to the plant's hygiene plan. Panels and trays are removed where the machine allows it. After washing, check that panels and covers are fitted and clamped before the machine is started.
Signs that something has changed
| Observation | Likely cause |
|---|---|
| More undersize in the oversize stream | Blinded or worn panel, thicker layer, changed stroke |
| Product moves slowly or stops on one side | Broken spring, loose mount, motor fault on one side |
| New noise or knocking | Loose fastener, bearing wear, panel loose |
| Deck twists or rocks | Spring failure or cracked support |
| Water on the floor at a dewatering screen | Full tray, blocked drain, torn panel |
Related: screening efficiency, sizing and selection.