Faults Preventing Water Pump from Discharging
1. Air in the Suction Pipe or Pump: If the suction pipe is not sealed properly or the pump is not filled with water before startup, air will be trapped inside. The presence of air will affect the normal intake and discharge of liquid, preventing the pump from operating normally. The solution is to check the seal of the suction pipe, repair any leaks, and ensure the pump is filled with water before startup.
2. Foot Valve Malfunction: The foot valve is a one-way valve installed at the bottom of the suction pipe to prevent backflow. If the foot valve is damaged or blocked by debris, liquid will not be able to enter the pump normally. In this case, check the foot valve's operation, remove the debris, or replace the damaged foot valve.
3. Impeller Blockage: The impeller is one of the important components of a centrifugal pump. If the impeller is blocked by debris, it will affect the flow of liquid and the generation of centrifugal force, causing the pump to fail to discharge water. The pump body can be disassembled, the impeller cleaned, and the debris removed.
Excessive Pump Vibration Faults
1. Pump Shaft and Motor Shaft Misalignment: The concentricity of the pump shaft and motor shaft is crucial for the normal operation of the pump. Misalignment will cause vibration and noise during operation. The solution is to readjust the concentricity of the pump shaft and motor shaft to within the allowable range.
2. Damaged Bearings: Bearings support the rotation of the pump shaft. Damaged bearings will cause uneven rotation, leading to vibration. Damaged bearings need to be replaced promptly.
3. Insecure Foundation: An unstable foundation for the fire pump will exacerbate pump vibration during operation. The foundation should be inspected and reinforced to ensure its stability and reliability.
Excessive Pump Power Faults
1. Excessive Flow Rate: If the actual flow rate of the pump exceeds the design flow rate, it will result in excessive pump power. This can be addressed by adjusting the opening of the outlet valve to reduce the flow rate and restore normal pump power.
2. Excessive Motor Speed: Excessive motor speed will also increase pump power. The motor speed needs to be checked to ensure it meets the pump's design requirements. If necessary, the motor speed should be adjusted.
3. Impeller-casing friction: When the clearance between the impeller and the pump casing is too small or friction occurs, it will increase the pump's operating resistance, resulting in excessive power consumption. The clearance between the impeller and the pump casing should be checked and adjusted or repaired.
