The process
Forming machines need blowing air at pressure for the moulds, and annealing lehrs use recirculation fans in the hot zone for uniform cooling of the ware. The lehr fans run inside the furnace as plug fans.
The gas at the fan
Clean air at elevated temperature from a dryer, oven or cooling duty. The selection is made at the hot density, with the shaft and bearings arranged for continuous hot running.
Selection for this duty
| Blade form | Backward curved or aerofoil for the best efficiency on clean gas |
| Material of construction | Mild steel |
| Drive and bearings | Direct coupled, shaft cooling disc, bearings in a pedestal outside the gas stream, allowance for thermal growth |
| Density at the fan | At about 250°C the gas density is close to 0.67 kg/m³, 56% 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. |
Delivers combustion, aeration and conveying air where the system resistance runs to several thousand millimetres of water column in a single stage. Client-stated blade types for the High Pressure Blower in general: Backward curved and radial tipped.
Industries
Other fans in glass forming and annealing lehrs
High Pressure Blower in other processes
CFBC BoilersCement Preheater KilnsVertical Roller Raw MillsCement Grinding MillsVertical Shaft Lime KilnsGlass Melting FurnacesFertilizer Granulation PlantsFertilizer Rotary Dryers and CoolersSulphuric Acid PlantsFluid Bed Dryers and CoolersFlour and Grain MillsCarbon Black PlantsAsh Handling SystemsCaptive Power PlantsPneumatic Conveying SystemsSilo Aeration and FluidisationWater and Wastewater Treatment PlantsGlass Batch HousesGas Based DRI PlantsSugar Dryers and SulphitationAnimal Feed MillsAlternative Fuel Handling in Cement Plants
Services on this fan
Fan and System Performance TestingRetrofit of Low Efficiency FansRotor Replacement and Performance EnhancementDynamic Balancing and Vibration AnalysisCondition Monitoring and TroubleshootingInstallation, Commissioning and After-sales Support
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.