Installation requirements for boiler induced draft fans
Before installing the induced draft fan of the boiler, the materials and tools for installation should be prepared first, and the mechanical parts of each part of the induced draft fan should be inspected. The impeller, main shaft and bearing should be inspected carefully. If damage is found, it should be repaired, and then the inside of the bearing box should be cleaned with kerosene. The following requirements must be paid attention to during installation and operation:
1. After the installation of the boiler induced draft fan fan is completed, move the rotor with your hand or lever to check whether there is any over-tightening or bumping phenomenon. Only when there is no such phenomenon can the trial run.
2. When the outlet of the induced draft fan of the boiler is installed at a certain angle, the rear disc can rotate properly to keep the plate in a horizontal position, and the flange surface of the angle steel №8～12 should be kept level.
3. When installing the fan of the boiler induced draft fan, the weight of the gas pipeline should not be added to the casing. Correct the size of the gap between the air inlet and the impeller according to the drawing, and keep the shaft horizontal.
4. When the boiler induced draft fan is installed with the air inlet pipe, it can be directly connected by the bolt of the air inlet itself. At this time, the air inlet is fixed by three countersunk screws.
5. When the boiler induced draft fan is installed with №8～12D type fan, use a dial gauge and a scale to measure the coaxiality of the fan main shaft and the motor shaft and the non-parallelism of the two ends of the coupling. The tolerance of non-parallelism of the two shafts is 0.05mm. The tolerance of non-parallelism on both ends of the coupling is 0.1mm.
Improvement of Sealing of Boiler induced draft fan
1. During the overhaul of the induced draft fan, the adoption of labyrinth seal and electric drill seal has stopped the innovation of the induced draft fan shaft seal. The reformed shaft seal is effective, and both seals have a high sealing effect.
2. Thinking about the later protection of the induced draft fan, it prevented the protection personnel from neglecting, but it was helpless to distinguish the winding position of the electric drill seal, and the drill seal was reversed. Therefore, the valve seat innovations of the remaining four induced draft fans did not adopt electric drill seals, and all adopted labyrinth seals.
3. After the innovation of the shaft seal of the induced draft fan, during the heating period, no smooth oil leakage was found in the shaft seal, which completely solved the effect of the bearing seal of the induced draft fan.
4. The shaft seal of the induced draft fan was changed to produce work, which eliminated the oil leakage of the induced draft fan shaft seal and temporarily disturbed the boiler team. Greatly reduced the operation of the induced draft fan caused by the failure, and simultaneously increased the operation cost of the induced draft fan.