Wheel in a New Form
The mixed flow wheel includes a wheel cone carefully matched to the inlet cone for precise running tolerances to reduce air leakage and turbulence, improve efficiency and lower sound.
The design of the wheel is optimized through CFD flow field simulation and repeated tests for optimum air performance, dramatically improving the efficiency over the traditional mixed flow wheel.
Die-formed and continuously welded, the wheel and flow passage components are of high precision, high strength and greater reliability.
High Balance Quality Grade
The wheel has been dynamically balanced twice: after the continuous welding process and after epoxy coatings applied on the surface. The balance quality grade reaches AMCA 204-G2.5 standard well above the international standard of G6.3. This helps greatly improve wheel balance, reduce vibrations and lower sound.
Optimum Sound Performance
The mixed flow wheel takes on intermediate performance characteristics between the axial and centrifugal wheel. Tests in the AMCA accredited laboratory (AMCA 300 Standard) show that it has such optimum sound performance that a bystander would hear a more bland sound.
Compact and More Cost-effective Design Without Scroll
Traditional fans with scroll are subject to the limitations of inlet distance from the scroll. For the YFISH fan designed without scroll, air is directly sucked through the inlet cone into the wheel and gets pressurized which will help reduce efficiency loss caused by turbulence and achieve better air performance. At the same time, the more compact design saves space, making it the best choice for more cost-effective box-type fans.
Performance Characteristics of Mixed Flow Type
The mixed flow fan takes on intermediate performance characteristics between the axial and centrifugal fan and features higher efficiency and lower sound. It allows greater airflow than the centrifugal fan and produces higher pressure than the axial fan. When the operating point moves up and down between A and B as shown here, the mixed flow fan has a smaller wheel diameter than the centrifugal fan at the same speed and has lower speed than the axial one with the same wheel diameter.
Better Sound Quality: Lower Sound Power
The sound quality of a mixed flow fan benefits from the low sound design as well as the reduced overall sound power. The sound chart compares units of same outlet diameters at an operating point. The mixed flow fan has a much lower sound level than the axial fan and double inlet centrifugal fan at all octave bands. Moreover, its sound mostly falls into the low octave band (62.5-250Hz) and a bystander would hear a more bland sound.
Aesthetically Pleasing Housing Constructed of Aluminum Alloy
The aesthetically pleasing housing constructed of aluminum alloy features high strength, light weight and tight sealing. Also, acoustical options can be customized (Options: soundproofing egg crate foam wall tiles or double layer soundproofing structure) for further improved performance.
Fans in Direct and Belt Drive Types for Flexible Model Selection
-- The direct drive type features high transmission efficiency, more compact design, minimal maintenance and no quick wear parts.
-- The belt drive type has a broader range of applications, allows more precise model selection and offers greater flexibility in responding to field conditions.
Different Discharge Options and More Flexible Applications
The direct drive type offers four different discharge options and the belt drive type seven. They can meet various design needs, making onsite installation easier and more convenient.
The duct mounted YFISH fan shall be of the mixed flow, belt or direct driven, inline type. It shall be designed without a scroll. The fan wheel shall be of the mixed flow type, constructed of steel and shall include a wheel cone carefully matched to the inlet cone for precise running tolerances. Wheels shall be statically and dynamically balanced up to AMCA 204-G2.5 standard.
The fan shall be tested and certified in accordance with AMCA Standard 210 & 300.The manufacturer shall obtain Production License for National Industrial Products and be certified by ISO9001.
The surface of the wheel shall be polished to remove any protuberances, welding spatters, burrs, sharp edges, scrap iron and greasy dirt before being finished with electrostatic epoxy coatings. The surface shall be a level one without sags, cracks, cockles or detachment. The surface shall remain free from corrosion and rust for at least ten years under normal operating conditions.
Drive Mechanism (Only for belt drive type)
Drive Type (Only for belt drive type):
The shaft shall be made of 40Cr steel and heat treated through homogenizing furnace to the hardness level of HB 286. The shaft material shall have a maximum limit of yield strength of 550MPa. Hard film shall be applied on the surface to avoid corrosion. The shaft shall also be dynamically balanced together with the wheel. The design speed of the shaft shall be at least 25% more than the maximum running speed of the fan.
Pulley: Fan pulleys shall be sized for a minimum of 150% of the driving power. Pulleys shall be cast iron, keyed and securely attached to the wheel and motor shaft. Conical type bushings shall be equipped for easy removal of the pulley.
Belt: The belt shall be grease and oil and static proof and resistant to high temperature.
Bearing: Independent metal bearings shall be used to support the shaft to avoid vibrations directly coming onto the motor. The bearing L10 rating life shall be in excess of 80, 000 hours at the maximum cataloged operating speed. The bearing shall be of permanently sealed type and pillow block metal ball bearing that can be lubricated. The bearing brand shall be internationally known, such as FYH and SKF.
Drive Support: Drive mechanism shall be supported by thick steel sheet finished with powder coatings to avoid corrosion. The belt tension can be adjusted through the adjusting bolt at the motor base. The design shall make sure the fan shaft and motor shaft is always parallel.
Belt Guard: The semi-enclosed belt guard shall be fitted to avoid injuries.
The motor shall match the fan load carefully. It shall be IP55 rated with Class F Insulation and Temperature Rise Class B. It shall be of B5 installation type for direct driven motor and B3 for belt driven motor. The bearing shall be lubrication-free ball type. The coefficient of power reserve of the selected motor shall be 110% to ensure safe operation. Motor types shall be selected based on the actual operating conditions, such as TEFC, 2-SPD, EXP, VFD and 60Hz.
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.