working-face forcing fan

A working-face forcing fan is an auxiliary ventilator configured to supply clean air directly to the face via ducting and a diffuser, establishing a positive-pressure jet that reaches the immediate cutting, drilling, or mucking zone. The objective is to maintain the target face quantity despite resistance from duct length, bends, and fittings, thereby ensuring effective methane dilution, removal of fumes after blasting or diesel operation, dust suppression, and acceptable thermal conditions.

Axial designs dominate due to high specific flow and compact installation. Where ducts are long or particularly lossy, contra-rotating stages provide higher static pressure at the same diameter. In methane-prone or dusty environments, explosion-proof motors, anti-static ducting, and compliant starters are specified. Variable-frequency control enables operators to trim performance as the face advances and the system curve shifts, avoiding over- or under-ventilation.

Face hardware should include a diffuser or jet nozzle that spreads velocity while minimizing turbulence and recirculation. Smooth inlet collectors, sealed duct joints, and properly supported hangers preserve pressure and reduce noise. Selection is based on the calculated total pressure—including allowances for leakage and aging—and a performance curve that delivers the duty near peak efficiency. Commissioning checks quantity, pressure, noise, and vibration at the face; ongoing monitoring of bearing temperature and vibration facilitates predictive maintenance and high uptime.

• Scope: local press-in ventilation at the working face
• Deliverables: quantity assurance, gas dilution, dust and fume control
• Enhancements: silencers near personnel, VFDs, sensors, EX compliance