Radialventilatoren vom Hersteller - Auswahl bei Volumenstrom, Druck und Baugröße
The Kaiser delivery program includes a series of centrifugal fans for applications that achieve a greater pressure increase with the same air volume compared to axial fans. Kaiser centrifugal fans are available in D, E and A series and are 100% speed controllable. The E series design is single inlet in a compact design with metal impeller and forward curved blades, while the D series design is double inlet, high air volume and also has forward curved blades. Series A has an out-of-airflow motor and forward-curved blades. Versions with backward curved blades are available on request. Centrifugal fans with backward curved impellers have lower power consumption, therefore at slightly higher pressure much lower airflow. Backward curved impellers are also used for fans without casing. These are designed by us to special customer requirements with welded or riveted wheels. The centrifugal fans are designed for optimum efficiency and a pressure-volume range which is very wide due to the controllability. The operation is designed for S1 (continuous operation).
Advantages of centrifugal fans (daial fans):
- The centrifugal fans are fully controllable, i.e. over the entire voltage range.
- Protection: The design of the protection class is according to IP 44, on request also in IP 54, as well as tropical insulated.
- The range of application covers all conceivable uses for conveying dust-free air and less aggressive, non-reactive gases or vapors.
- The exact temperature range can be found in the corresponding data sheet in the radial list, but can be assumed as a general rule at a maximum continuous temperature of 60 °C.
Design (construction):
- Centrifugal fan single inlet, impeller with forward curved blades, design product series E,
- centrifugal fan double inlet, impeller with forward curved blades, design product series D,
- Centrifugal fan, impeller with backward curved blades, with and without casing, type according to customer requirements.
⇒ Selection Guide Centrifugal Fans
Click on the type designation in the overview for more detailed product information.
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Series E with bulit-in motor (motor in the airflow) | |
|---|---|
 |
|
| design type | radial fan |
| Construction | single inlet |
| impeller | forward curved blades |
| air flow direction | over motor and cooling |
| speed controllable | yes, 100% |
| Applications |
|
| Material | |
| material | steel ring |
| surface | galvanized or powder-coated |
| impeller | galvanized steel sheet |
| stainless steel (V2A , V4A) | possible |
| Series D with bulit-in motor (motor in the airflow) | |
 |
|
| design type | radial fan |
| Construction | dobble sided inlet |
| impeller | forward curved blades |
| air flow direction | over motor and cooling |
| speed controllable | yes, 100% |
| Applications |
|
| Materialeigenschaften | |
| material | steel ring |
| surface | galvanized or powder-coated |
| impeller | galvanized steel sheet |
| stainless steel (V2A , V4A) | possible |
| Series A with bulit-on motor | |
 |
|
| design type | radial fan |
| Construction | single inlet |
| impeller | forward curved blades |
| air flow direction | motor outside the airflow |
| speed controllable | yes, 100% |
| Anwendungen |
|
Further designs are available are under the menue link "special shapes."
Selection guide centrifugal fans
The centrifugal fans are staggered so that the pressure increases.
Radial Fans Series E
Radial Fans Series D
Radial Fans Series A
High performance radial fans: Working principle and areas of application
Centrifugal fans (radial fnas) are equipped with asynchronous motors together with an internal rotor, which are completely enclosed in themselves, and their outer surface has cooling fins. Optimal heat dissipation is ensured by the position of the motor, which is located in the air flow of the fan. Since the characteristic curves of the fans have a continuous course, they can be used in the entire range of characteristic curves. The areas of application include all areas with larger air volume conveying. These include ventilation and air-conditioning technology, mechanical engineering, apparatus engineering and plant construction, as well as use as add-on fans for heat exchangers.
Materials: Ball bearings, impellers, corrosion protection
The fans have deep groove ball bearings with special internal clearance, which are permanently lubricated with a special ball bearing grease. This allows use in the temperature range from -30 °C to +180 °C. A cold grease for temperatures below -30 °C is also available on request. The bearings are sealed by means of two sealing washers. Spare ball bearings can be supplied if the valve size is specified. The radial impellers as well as the inlet nozzles are made of galvanized sheet steel, while the fan housing is wet-painted or galvanized several times - powder coating is available on request. In order to achieve optimum corrosion protection, the motors are coated with a paint protection layer after assembly. Optionally, galvanized intake protection grilles can be fitted. In addition, the fans can be manufactured in stainless steel V2A and V4A on request.
Motor protection by means of thermal contacts
For safe overheating protection, the motors are equipped with thermal contacts (TC) or temperature monitors as standard. As temperature-dependent switching elements, the contacts are embedded in the winding of the motors in an insulated manner. If overheating occurs, the thermal contacts open an electrical contact. Whereas in the case of AC motors this contact is built directly into the circuit and the fan switches itself off and on, in the case of three-phase motors it is connected to a special external switch which interrupts the voltage conductors. After a malfunction or cooling down, there is normally no automatic restarting.
Electrical connection, installation position and air flow direction
The electrical connection of the fans is made via terminal boards in terminal boxes located on the back of the motor. The cables are fed through cable glands with IP 44 protection - glands with IP 54 protection are available on request. An operating capacitor is already connected as standard on fans with AC design. This eliminates the need for an external terminal box.
The installation of the fans is generally possible in any position. Since condensation can form in the motor in the event of large fluctuations in ambient temperature, condensation drain holes are provided on both motor bearing shields. The respective mounting position depends on the type of fan insert. When ordering a centrifugal fan, the mounting position should also be specified, since the fans are equipped with condensation water holes and these must be mounted accordingly.
Notes on the selection of a centrifugal fan: Centrifugal fan selection volume pressure curve
The basic requirement in selecting the appropriate fan with respect to the application should be that it is at the performance point or in the range of
optimum efficiency when operating the ventilation system, in order to be able to achieve the best possible operating point. An ideal application range is between a volume flow of 4,000 and 5,000 m³/h. If the operating point for fan speed control is at operating point 2, it is shifted on the resistance characteristic curve. The fan should not be operated at operating point 1 of the characteristic curve, free intake and free discharge, as the load on the drive motor at this point is extremely high. Operation above operating point 3 on the characteristic curve should also be avoided, as the efficiency of the fan is lower there.
If you have any further questions about Kaiser centrifugal fans, please feel free to write to us via contact form or e-mail. Alternatively, you can reach us by phone. Kaiser Ventilatorenbau will be happy to assist you with personal advice.