Analysis of working principle and commonly used installation and maintenance methods of induced draf
The working principle of induced draft fan of heating and hot water boiler: it relies on the input mechanical energy to increase the gas pressure and drain the gas side by side. It is a kind of driven fluid machinery. The working principle of induced draft fan of heating and hot water boiler is basically the same as that of turbine compressor, but because the gas flow rate is low and the pressure changes little, it is generally unnecessary to consider the change of gas specific volume, that is to say, gas is treated as incompressible fluid. Heating hot water boiler induced draft fan is widely used in ventilation, dust discharge and cooling of factories, mines, tunnels, cooling towers, vehicles, ships and buildings; ventilation and diversion of heating hot water boilers and industrial furnaces and kilns Wind; cooling and ventilation in air conditioning equipment and household electrical equipment; drying and delivery of grain; wind tunnel air source and hovercraft aeration and propulsion, etc.
The common installation, debugging and maintenance methods of induced draft fan for heating and hot water boiler are as follows:
1. Check-before installation, check if there is any sundries in the fan, if so, remove it; dial the impeller, if there is a scraping phenomenon, find that the inappropriateness must be adjusted in a timely manner.
2. The foundation-concrete floor with a thickness of not less than 300mm, the basic level of the surface shall be set to be not less than 300mm according to the perimeter of the frame and about 100 mm (water proof) above the surrounding floor; and the floor and the roof with the weight of the fan can be carried.
3. Trial operation-the air valve must be closed before starting, so that the fan can start under no load. After reaching the normal speed, the air valve can be gradually opened until the rated working condition. In the course of operation, the current should be strictly monitored and must not exceed the rating. After 20 minutes of operation, the fan should check whether the temperature rise of the bearing box is normal (the temperature rise shall not exceed 40 and the surface temperature shall not exceed 70 ).
4. Maintenance-Fan maintenance must first stop and power off; timely replacement of lubricant (oil or grease) according to the actual situation; When the vibration of the fan is aggravated, the bearing temperature rise is too high, the motor current is too large, and the body is overheated, the cause should be found out in time and the fault can be eliminated before it can be run again.
