Controls and ancillaries
Solenoid valve (sonic horn)
Also known as pilot valve, sonic horn solenoid, quick-exhaust valve.
A solenoid valve is the electrically-actuated pilot device that admits compressed air to a sonic horn on command from the cycle controller. The valve opens for the programmed pulse duration (typically 5–15 seconds), letting plant air at 4–7 bar drive the horn's diaphragm into resonant oscillation. When the valve closes, the air supply is cut and the horn falls silent until the next pulse.
Specification
For most industrial sonic-horn installations, the solenoid valve is:
- ATEX / IECEx certified for the local hazardous-area classification
- Sized for the horn's peak airflow (8–14 Nm³/min typical)
- Quick-exhaust type, to allow rapid pressure drop at the end of each pulse
- Voltage-rated for the site's instrument-control voltage (typically 24 VDC or 110/230 VAC)
- IP65 or IP66 weatherproof if mounted externally
Wear and replacement
The solenoid valve is the most-replaced wear part on the periphery of an industrial sonic horn — typical service life of 1–3 years before coil or seat replacement. Routine inclusion in the spares package is standard practice.
Related terms
Related terms
- Sonic hornA sonic horn is a pneumatically-driven low-frequency sound emitter (typically 60–400 Hz at 140–180 dB SPL) used to dislodge particulate fouling from boilers, ESPs, baghouses and process vessels.
- Pneumatic acoustic cleanerA pneumatic acoustic cleaner is a sonic horn driven by compressed plant air. The pneumatic design dominates industrial acoustic cleaning because it has no electrical parts in the gas path.
- Cycle controller and sequencerA cycle controller programmes the firing pattern of one or more sonic horns — duration, interval, sequence, zone grouping. Either a dedicated standalone unit or a PLC subroutine.
- Compressed air (industrial)Compressed air at 4–7 bar from plant or instrument-air systems drives industrial sonic horns. Consumption typically 8–14 Nm³/min during a firing burst.