It shall be vane-axial fan with airfoil blades. The fan shall be direct driven and in a cylindrical structure. Behind the impeller in the cylindrical body, there shall be guiding vanes for airflow straightening. The guiding vane shall have a three-dimensional curved surface in line with flow field characteristics for better air performance and static efficiency.
The fan shall be tested and certified in accordance with AMCA Standard 210 & 300. AMCA Seal for Efficiency Sound and Air Performance shall be tagged on each fan before leaving the factory. The manufacturer shall obtain Production License for National Industrial Products and be certiﬁed by ISO9001, ISO14001 and OHSAS18001.
It shall be an axial impeller with airfoil blades of variable angles to ensure that right models can be selected for various operating conditions. The impeller shall have a vortex hub to avoid turbulence and airfoil blades of optimum air performance. Stable airflow and low noise shall be ensured at the maximum running speed. Die formed with cast aluminum, the hub and blades shall be strong enough to maintain operational reliability and safety at a speed 120% of the maximum speed. The impeller should be subject to dynamic balancing tests up to AMCA 204- G2.5 balance quality grade so that its operational stability can be improved and service life extended.
The fan housing shall be made of quality carbon steel and continuously welded and use lap joint flanges. For the fan housing with the impeller diameter of less than 500mm, the carbon steel thickness should be no less than 2mm; For the fan housing with the impeller diameter between 500 and 1000mm, the carbon steel thickness should be no less than 2.5mm; For the fan housing with the impeller diameter of over 1000mm, the carbon steel thickness should be no less than 3mm. All these are to ensure the fan’s operational safety and reliability over a long period of time and extend its service life.
The surface of the fan shall be polished to remove any protuberances, welding spatters, burrs, sharp edges and scrap iron. Then it shall undergo the processes of oil removal, pickling, parkerizing, applying putty before being finished with electrostatic epoxy coatings processed under high temperature for strong adhesion. The surface shall be a level one without sags, cracks, cockles or detachment to avoid corrosion over a long period of time.
It shall be of B5 or B14 installation type. The motor is IP55 rated with Class F Insulation (Class H Insulation for Smoke Removal) and Temperature Rise Class B. Lubrication-free ball bearings shall be used. The coefficient of power reserve of the selected motor shall be over 110% to ensure safe operation. As the motor is located inside the fan, it is the supplier that shall provide the appropriate external junction box based on the actual application.
Spark Resistant Certification (Only for explosion- proof type)
The fan shall include AMCA 99 Type C Spark Resistant Construction and an explosion-proof motor. The Ex Certificate of Conformity shall be obtained. The manufacturer shall have the Production License for Explosion-Proof Electrical Products.
Fire Certification (Only for smoke removal type)
As a fan used for smoke removal, it shall meet the relevant requirements of GA 211-2009 High Temperature-Resistant Test Methods for Smoke and Heat Exhaust Ventilators, CNCA-C18-02：2014 China Compulsory Certification on Fire Protection Products, CCCF-HZFH-03 China Compulsory Certification on Fire Protection Products and Smoke Exhaust Equipment. The fan shall be able to run continuously for over 30 minutes without any failures under the temperature of 280 degrees. The type test report issued by state authorized test agencies and a CCCF certificate shall be obtained.
As a fan used for smoke removal, it shall also meet the relevant requirements of EN12101-3 Smoke and heat control systems- Part 3: Specification for powered smoke and heat exhaust ventilators. The fan shall be able to run continuously for over 120 minutes without any failures under the temperature of 300 degrees to ensure the required heat resistance level. The test report issued by TUV SUD and Class 1A certificate of CoC shall be obtained.
A permanently fixed aluminum nameplate shall clearly display the fan number, product model and serial number (a unique ID for each fan) so that the parts used can be traceable by customers.