The process
Jute batching and spinning release fibre and dust that is drawn to dust collectors, and the mill floors are hot. Open or radial wheels on the extraction, roof extractors for the heat.
The gas at the fan
Fibrous or stringy material that wraps a shrouded wheel. An open or straight radial impeller, spark resistant where the fibre is combustible, placed before or after the collector as the material allows.
Selection for this duty
| Blade form | Radial tipped, or backward inclined where the fan sits after the collector |
| Material of construction | Mild steel |
| Drive and bearings | Direct coupled or belt driven; belt drive where the duty point may need tuning at site |
| Also specified | Spark resistant construction with non-ferrous rubbing parts, shaft seal, earthing and a flameproof or increased safety motor; access doors on the scroll and a wheel that can be cleaned in place |
| Density at the fan | At about 35°C the gas density is close to 1.15 kg/m³, 95% of standard air. Pressure developed and power drawn fall in the same ratio, so the selection is made at this density and the motor is checked at cold start. |
Moves air through a plant or building for fresh air supply, heat removal and fume dilution where the system is ducted. Low pressure, long hours, so efficiency and noise set the selection. Client-stated blade types for the Ventilation Fan in general: Backward inclined and forward curved.
Industries
Other fans in jute mills
Ventilation Fan in other processes
Services on this fan
Information needed to select or quote
- Duty point. Volume flow and static pressure at the fan inlet, with the gas density and temperature or the conditions to derive it.
- Operating conditions. Site altitude, normal operating temperature and continuous or intermittent duty.
- Gas stream. Dust loading and particle size, corrosive species, moisture, upset temperature and any tendency of the material to deposit on the impeller.
- Mechanical. Rotation viewed from the drive end, discharge orientation and motor power.
