- Fan Type
Fan shall be rooftop centrifugal exhaust type with aluminum backward inclined centrifugal wheel. The inlet Venturi shall have round curved section to smoothly transit the air to the wheel cone. The wheel shall be statically and dynamically balanced to Level G2.5 as per AMCA204 standard.
- Quality Standards
The fan shall be tested in accordance with AMCA Standard 210 and 300. The manufacturer must own the production license for industrial products and ISO9001 quality system authentication.
Wheel shall be propeller-type axial wheel. The blade streamline of the wheel shall be optimized by 3D curved optimal design. Wheel cutting the air flow asymptotically, airflow direction is stable and high in consistence. Blades shall be molded by mold stamping at one time. Use special tooling on installation angle of blade and connection between blade and hub to ensure accuracy, so as to ensure processing quality and high reliability. The wheel shall be statically and dynamically balanced to Level G2.5 as per AMCA204 standard.
- Fan Materials
The housing of the fan shall be made of cold rolled panel with epoxy coating [options: colour changes are available] no less than 2mm thickness. The wheel shall be made of steel with epoxy coating to ensure the reliability of the core components and extend the operation life. The material of bent pipe bracket is 20# seamless steel tube, using professional processing equipment to ensure the quality.
The fan shall be equipped with spin-formed bell mouth. Wheel shall be in precision fit with bell mouth. Guide air to flow smoothly, so as to reduce leakage loss and turbulent current.
The fan shall be equipped with firm bent bracket, so as to prevent the fan from generating resonance while running and ensure reliable structure and unique shape.
The fan shall be equipped with defend hood in indoor side to ensure personal safety.
The fan shall be equipped with defend hood or weather hood in outdoor side to meet the application requirements. And the structure of weather hood shall be meet the requirement of weather proof （Weather hood in outdoor side: Airflow angle is 45 for exhaust type, Airflow angle is 90 for supply type.
Sidewall hanging structure
The fan is made up with indoor defend hood, propeller-type axial wheel, bent pipe bracket, angle iron for installation, outdoor defend hood, motor, belt driven parts (for belt drive type only), and connecting box.
The fan is made up with indoor defend hood, cabinet structure for wear wall, propeller-type axial wheel, bent pipe bracket, angle iron for installation, outdoor weather hood, motor, belt driven parts (for belt drive type only), and connecting box.
Direct drive type
The fan wheel shall be directly connected with the motor. The motor shall adopt B5 installation structure, and its protection grade shall be IP54, while insulation class F and temperature rise B. The motor bearing shall be self-lubricating ball bearing.
Junction box of motor: Since the motor is within the fan, the supplier shall provide junction boxes to lead the wire out of the fan, and correct types of junction boxes shall be selected according to the specific applications, such as fire protection type, explosion proof type and common type.
Belt drive type
Shaft: the fan shaft shall be made of 40Cr and hot-treated with homogeneous furnace to ensure that the hardness grade reaches HB286 and the yield limit reaches 550MPa, and anti-corrosion hardening treatment shall be conducted on the surface, and whole dynamic balancing shall be conducted on such surface together with the impeller. The designed operation speed shall at least exceed 25% of the maximum operation speed of the fan.
Belt pulley: the belt pulley shall have specifications as per 150% of the drive power, be made of cast iron, and be fixed with taper lock bush to facilitate dismantlement.
Belt: the belt shall be resistant from oil, heat and electrostatic discharge.
Bearing: independent metal bearing shall be used for supporting the fan shaft to prevent vibration from directly applying onto the motor. The bearing shall be sealed-for-life, self-lubricating ball bearing of pillow block type and metal material. At the maximum rotation speed as indicated in the catalogue, the bearing life shall be no less than (L-10) 80000 hours. And international famous brands shall be selected, such as FYH, and SKF, etc.
Extension lubricating oil tube for bearing: the extended lubricating oil tube is used outside the machine for conveniently filling grease to the bearing without dismantling the fan. And the material of the oil tube shall be copper.
Support: the driving device shall be supported with powder-coated anti-corrosion steel plate, the belt shall be adjustable, and the design of the motor base shall ensure the parallelism of the fan shaft and the motor shaft.
Motor: The motor shall match with the fan load, and B3 installation structure shall be adopted. The protection grade of the motor shall be IP54, while insulation class F and temperature rise B. The motor bearing shall be self-lubricating ball bearing. And TEFC, 2-SPD, EXP, VFD, 60Hz and other correct motor types must be selected according to the specific working conditions.
- Explosion-proof Structure (Only for explosion-proof type)
Fan shall conform to Spark C explosion-proof structure according to AMCA99 Standard. The inlet shall mount copper ring and the motor shall adopt explosion-proof type. The whole fan should own CNEX certification and the manufacturer must own the production license for anti-explosion electric products.
Relevant accessories shall be provided according to the specific requirements for each set of equipment, such as air volume control damper, gravity-held air back draft damper , fireproof regulating damper, fire damper, Stainless steel blades , Stainless steel fasteners, etc.
Permanently fixed aluminum nameplate shall be fixed on fan body clearly display fan mark, product model and serial number (i.e.: unique ID for each fan), so that the customer can use this number to find out the parts used.
- Acceptable Manufacturers
Qualified suppliers shall have an AAA credit rating. Providing INFINAIR or similar products, with their design based on WEX models of INFINAIR.