... also has high security and reliability. 1. Fan rotor is direct welding by rotor and blades, In order ... to meet the design requirements of fan vibration and noise,adopt double-sided dynamic balance, ... balance achieved G6.3.2. The fan blade, rotor and grid is all powder sprayed, the ... Bright beautiful appearance is not easy oxidation discoloration3. Fan normal ambient temperature:-40°C~ +60°C, ...