01 · Engineering Overview
Construction-Stage Air Supply Through Tunnel Ventilation Ducts
SDF is a tunnel construction ventilation fan series intended for delivering fresh air through ventilation ducting toward underground working areas. The fan is selected according to the required airflow and the resistance of the complete duct route.
Tunnel length alone does not determine the fan model. Duct diameter, duct length, leakage, bends, fittings, installation position and the required airflow all affect the operating pressure. The final fan configuration should therefore be reviewed against the actual project operating point.
01 · Airflow
Deliver Fresh Air to the Working Face
The ventilation system supplies outside air through flexible or rigid ducting toward the active underground work area.
02 · Pressure
Overcome the Complete Duct Resistance
Pressure selection should include straight duct loss, elbows, fittings and other resistance along the ventilation route, while leakage should be reviewed because it reduces useful delivered airflow.
03 · Configuration
Match the Fan Arrangement to the Duty
Single-stage, counter-rotating and long-distance series arrangements can be reviewed according to the required airflow and system pressure.
For the complete construction-stage airflow route, duct resistance and maximum ventilation-distance logic, see Tunnel Construction Ventilation System →
02 · Product Configuration
SDF Configurations for Different Tunnel Ventilation Duties
QIYUE’s SDF product range includes multiple construction-ventilation configurations. Configuration should be confirmed according to airflow, system pressure, tunnel route and project operating strategy rather than being selected only from motor power.
Low-Noise VFD Counter-Rotating
Variable-frequency counter-rotating configuration for adjustable construction-stage tunnel ventilation.
Conventional VFD Counter-Rotating
Counter-rotating SDF arrangement with variable-frequency control according to project airflow requirements.
Single-Stage VFD
Single-stage tunnel ventilation configuration where the required operating point does not require a counter-rotating arrangement.
Long-Distance Series Multi-Stage
Series fan arrangement for longer ventilation routes where total duct-system resistance requires additional pressure capability.
Motor Configuration
Permanent-Magnet Motor
Permanent-magnet motor configuration can be reviewed where required by the project.
Motor Configuration
Conventional Motor
Conventional motor configuration is available according to the confirmed operating point and project electrical supply.
03 · Verified Performance
Confirmed SDF Reference Performance Data
The following figures are the SDF performance data currently confirmed in the available QIYUE technical records. They are reference ranges for preliminary screening and should not replace project-specific operating-point selection.
MODEL
MOTOR
SPEED
AIRFLOW
m³/min
m³/min
TOTAL PRESSURE
Pa
Pa
IMPELLER
SDF-4.5
2 × 4 kW · 2P
2900 r/min
110–165
370–3000
Aluminum alloy
SDF-5
2 × 5.5 kW · 2P
2900 r/min
160–240
275–2960
Aluminum alloy
SDF-5
2 × 7.5 kW · 2P
2900 r/min
180–265
315–3520
Aluminum alloy
SDF-5.6
2 × 11 kW · 2P
2900 r/min
215–340
420–4530
Aluminum alloy
Engineering note: do not select an SDF fan only from maximum airflow or installed motor power. Confirm the required airflow and total system resistance at the actual project operating point.
04 · Fan + Duct Selection Logic
The SDF Fan Must Be Selected with the Ventilation Duct
The same SDF fan can operate at different airflow values depending on the connected system resistance. For construction-stage ventilation, the fan and duct route should therefore be evaluated together rather than treating the fan as an isolated airflow source.
01 · Tunnel Length
Current + Maximum Distance
Selection should consider the expected maximum ventilation route, not only the early construction stage.
02 · Duct Diameter
Diameter Affects Resistance
Duct diameter, route and fittings should be confirmed before the required fan pressure is finalized.
03 · Leakage
Useful Face Airflow
Duct leakage can reduce the airflow that is actually delivered to the heading face.
04 · Operating Point
Airflow + Pressure Together
Use the required airflow and system resistance together when comparing candidate SDF configurations.
Related Engineering Guides
05 · Typical Applications
Construction Ventilation for Tunnel and Underground Projects
The SDF series is primarily positioned for construction-stage duct ventilation. Final suitability depends on the actual system resistance and project conditions.
01
Road Tunnel Construction
Ducted fresh-air delivery during excavation and tunnel construction.
02
Railway Tunnel Construction
Long-distance ventilation where the increasing duct route creates pressure loss.
03
Underground Construction
Working-area ventilation for underground construction requiring ducted air supply.
For completed road-tunnel longitudinal ventilation or jet-fan duty, review the SDS Tunnel Jet Fan →
06 · Selection Information
What to Send for SDF Tunnel Fan Selection
The following project data allows the fan duty and suitable SDF configuration to be reviewed against the actual tunnel ventilation route.
01
Airflow
Required operating airflow in m³/min or m³/h.
02
Pressure
Required total pressure or calculated ventilation-system resistance.
03
Tunnel Length
Current tunnel length and expected maximum ventilation distance.
04
Duct Diameter
Ventilation duct diameter, duct type and available leakage information.
05
Site Conditions
Altitude, installation position and tunnel construction conditions.
06
Electrical
Voltage, frequency, phase and motor or VFD requirements.
Pressure Not Available?
Send the tunnel length, duct diameter, duct route and required airflow. The ventilation-system resistance can then be reviewed before confirming the fan model.
Technical Questions
SDF Tunnel Ventilation Fan Questions
01
What Is the SDF Fan Mainly Used For?
SDF is primarily used for construction-stage tunnel ventilation and ducted fresh-air delivery to underground working areas.
02
Is Every SDF Fan Counter-Rotating?
No. QIYUE’s available product directions include counter-rotating, single-stage and long-distance series arrangements. The correct configuration depends on the project duty.
03
Can SDF Fans Use Variable-Frequency Control?
Variable-frequency configurations are available within the SDF product range. Final motor and control configuration should be confirmed for the project.
04
Can a Permanent-Magnet Motor Be Supplied?
Permanent-magnet and conventional motor configurations can be reviewed according to the tunnel ventilation project requirements.
05
How Is an SDF Model Selected?
Selection should be based on the required airflow, total system resistance, tunnel and duct length, duct diameter, installation conditions and electrical supply.
06
Can SDF Be Selected Only from Motor Power?
No. Motor power alone does not define the required operating point. Airflow and system resistance should be confirmed first, then the suitable SDF configuration can be reviewed.
Send Your Operating Conditions
Airflow, pressure, gas medium, temperature, voltage and quantity.