- 6
-
A
- Air is introduced to the suction side ▶ Check the tightness of the gasket and screws in the suction pipe.
- If vortex is formed in the suction tank, an anti-vortex device must be installed.
- NPSH insufficient ▶ The NPSHa value must be recalculated. This value must be greater than the NPSHr value at the required flow rate.(Example: NPSHa 〉 NPSHr)
NPSHr)Otherwise, the number of elbows and connections must be minimized and the suction pipe must be redesigned to prevent backflow when the fluid is introduced into the impeller.
- 5
-
A
- Insufficient water level ▶ Restart after sufficiently removing air. If the pump was run dry, disassemble the pump and check for damage before running it.
- Reverse rotation ▶ Check if the rotation direction is incorrect. Randomly change two of the three wires of the three-phase motor and connect them.
- Check for foreign substances clogging the strainer of the suction pipe or clogging the impeller inlet.
- Check for impeller damage
- 4
-
A
- Cavitation noise ▶ Discharge pressure gauge hunts quickly ▶ See section 1.3
- Impeller interference ▶ Check and readjust impeller gap
- Noise from abnormal fluid flow due to complicated suction piping ▶ If there are many bends such as elbows and the length is long, the piping size must be significantly redesigned
- 3
-
A
- Water entering the housing and bearing damage ▶ Clean the inside of the housing and replace the bearing
- Rust on the upper part of the bearing due to long-term non-use ▶ Same
- Bearing damage due to incorrect shaft alignment ▶ Check the coupling condition, replace damaged parts, and realign the shaft
- Bearing damage due to insufficient lubricant (oil, grease) ▶ Replace damaged parts and maintain the appropriate amount of lubricant used. However, in the case of grease, excessive injection may cause bearing overheating and damage, so refer to the user manual.
- 2
-
A
- If the system head (discharge pipe) is greater than the pump head of the order specification
▶ Increase the size of the discharge pipe or reduce the number of pipe connections to reduce the system head
▶ Increase the impeller outer diameter (D2). (Caution: The motor capacity may increase.)
- Wear and corrosion of the contact area (casing, impeller) ▶ Replace parts
- NPSH insufficient ▶ Refer to Section 1.3
- Reverse rotation ▶ Refer to Section 2.2
- Refer to Section 2.3
- 1
-
A
- Discharge pressure gauge failure -> Shut off to check if the pressure and current are consistent with the performance report
- Refer to 2.3, 5.2, 5.3, and 5.4
