Impellers
AXV impellers, hubs and blades are made off pressure-cast aluminium alloy, the aerodynamical profile guarantees high efficiency and low noise levels. The pitch angle is adjustableduring standstill. The variable number of blades the expands the performance range.
Motor
Wolter uses closed squirrel cage motors according to IEC 34, if required also in accordance with EPACT. Standard motors are class F with IP 55 protection class. Multi speed versions with 2 or 3 speeds (Dahlander circuit or separate windings) are also available, as well as explosion-proof versions or specific industrial executions such as marine-type fans. The motor bearings have a L 10 life.
Forms Of Running
Wolter AXV/BXV axial flow fans are available for all forms of running. The above chart shows all standard forms of running. Please indicate the required configuration when ordering. Without specific instructions, fans will be delivered in configuration S. Arrows outside the fan casing indicates the correct direction of rotation and airflow.
Fan Performance Curves
The performance curves for these fan types have been established in mounting position D (according to DIN 24 163, part 1, duct connected to inlet and outlet sides) and represent the total pressure increase Dpt as a function of the volume flow. The dynamic pressure pd2 refers to the flange cross-sectional area at the of the fan.
Sound Levels
The sound levels are in accordance to DIN 45 635, section 38. The performance curves show the unweighted total sound power levels LW. The octave sound power level is important for the selection of suitable sound attenuators. It is calculated as follows: LWOkt = LW + LWrel
The relative octave sound power level LWArel at octave medium frequency can be taken from the tables. The A-weighted octave sound power level is obtained by applying the A-filter (see page 7): LWAOkt = LWOkt + LWrelA
The A-weighted sound power level LWA is obtained by logarithmic addition of all A-weighted octave sound power levels (see page 7). The sound power level on suction and outlet sides are approximatley equal. LW5 ≈ LW6 , LWA5 ≈ LWA6 , LWA5 ≈ LWA - 3
The sound power level radiated from the casing, LW2, according to DIN 45 635, part 38, is calculated by the following approximation formula: LW2 = LW - 15 dB(A)
The A-weighted sound pressure level LPA at a distance of 1 metre is calculated approximately by deducting 7 dB(A) from the A-weighted sound power level LWA.
It is important to note that reflexion and environmental characteristics as well as resonant frequencies influence the sound pressure levels in different ways.