After a long trial, the constant pressure fire pump will be insufficient, some even have no oil and other failures, the main reason is too much wear. The wear position of the fire pump is mainly in the active shaft and bushing, the center hole of the passive gear center hole and the shaft pin, the inner cavity of the pump casing and the gear, the gear end face and the pump cover and the like. When the pump is not up to the technical requirements of the technical indicators, we should first remove the pump, to see the extent of the wear and tear of the location, to take the corresponding means to repair.
1. The active shaft and bushing wear after the repair :
Gear pump drive shaft and bushing wear, the gap increases, will affect the amount of pump oil. In case of this, it can be used to repair the active shaft or bushing method to restore its normal coordination gap. If the shaft wear bushing slightly, just press the old bushing replaced after the standard size, with the gap can be restored to the permissible range. If the drive shaft and bushing wear and clearance severely exceed the standard, not only to replace the bushing, and the driving shaft is also the application of chrome or vibration welding method will increase its diameter and then grinding to a standard size, recovery and bushing with the requirements.
2. Repair lubrication oil pump shell shell crack repair: shell crack available 508 cast nickel copper electrode welding. The weld shall be tight and air hole, and the surface flatness error of the pump cover is not more than 0.05 mm.
3. The use of gear wheel :
Gear pump gear wear is mainly in the tooth thickness, and the gear face and tooth top wear are relatively light. Gear in the tooth thickness of the parts are unilateral wear, so the gear can be used to turn 180 degrees. When the gear face wear face can be removed, and grinding lubrication oil pump shell joint surface, to ensure that the gear face and pump cover the gap in the standard range.
