1. Scope and purpose
This manual describes standard maintenance procedures for industrial centrifugal pumps, including mechanical seal replacement, detailed impeller inspection, and performance testing procedures. These actions are critical to prevent leaks, reduce vibrations, and ensure efficient operation of pumping equipment in accordance with ISO 9906 and DSTU EN 809. standards.Maintenance should be performed when signs of wear, seal leaks, or reduced pressure are detected.
2. Safety measures
ATTENTION: Before starting any work, it is necessary to complete the blocking and marking (LOTO) procedure. Ensure that the pump is completely de-energized and that the stop valves on the suction and discharge lines are closed and locked.
The use of personal protective equipment (PPE) is mandatory: safety glasses, chemical-resistant gloves, steel-toed safety shoes and protective coveralls.
If the pump has been used for pumping hazardous liquids, be sure to flush it and make sure there is no residual pressure in the system.
3. Tools and materials
| Tool/Material | Specification | Quantity |
|---|
| Torque wrench | The range is 10-100 Nm | 1 |
| Bearing/wheel puller | According to the size of the shaft | 1 |
| Vernier caliper | Accuracy 0.05 mm | 1 |
| A set of probes | 0.05-1.00 mm | 1 |
| Surface cleaner | For degreasing metals | 1 |
| Lubricant for seals | Compatible with the environment | 1 |
4. Inspection before service
| Element | Verification | Criteria (Accept/Reject) | Notes |
|---|
| Pump housing | Visual inspection for cracks | No visible defects | - |
| Vibration | Measurement of vibration level | Within ISO 10816 | - |
| Bearing temperature | Measurements | < 80°C | - |
| Inlet/outlet pressure | Manometers | According to the pump curve | - |
5. Step-by-step procedure
- Insulation and drainage: Close the valves. Open the drain hole and drain the liquid completely. Error: Incomplete draining can cause hazardous substances to spill.
- Disassembly: Dismantle the clutch protective cover. Disconnect the coupling. Unscrew the fastening bolts of the pump housing evenly crosswise.
- Inspection of the impeller: Remove the impeller with the puller. Inspect the vanes for cavitation wear, erosion or mechanical damage. Error: Using a hammer to remove the wheel can damage the shaft.
- Mechanical seal replacement: Remove the old seal. Clean the seat on the shaft. Install a new seal. The friction surfaces must be perfectly clean. Use the recommended lubricant. The gap between the shaft and the seal should be 0.1-0.2 mm.
- Reassembly: Put the wheel back on. Check the axial clearance (allow 0.15-0.30 mm). Tighten the housing bolts with a torque wrench (tighten to 45 Nm for M12 bolts).
- Startup: After assembly, rotate the shaft by hand to ensure there is no rubbing. Start the pump by gradually opening the discharge valve.
6. Inspection after service
| Test | Expected result | Actual result | Status |
|---|
| Hermeticity | No leaks | - | - |
| Vibration | < 2.8 mm/s RMS | - | - |
| Current consumption | According to the passport | - | - |
7. Troubleshooting
| Symptom | Probable cause | action |
|---|
| Seal leakage | Damaged friction surface | Seal replacement |
| High vibration | Wheel imbalance | Balancing or replacement |
| There is no pressure | Wrong direction of rotation | Checking the motor connection |
8. Service schedule
| The task | Frequency | Duration | Level |
|---|
| Overview of sources | Every week | 15 min | Low |
| Vibration test | Every month | 30 min | Average |
| Seal/bearing replacement | Annually | 8 hours | Tall |
9. Spare parts
| Description of the spare part | Specification | Category UNITEC |
|---|
| Mechanical sealing | Silicon carbide material | Pump seals |
| Working wheel | AISI 316 stainless steel | Pump parts |
| A set of bearings | C3 gap | Bearings |
Ordering spare parts is available on our website: UNITEC-D E-Catalog.
10. Links
- ISO 9906: Centrifugal pumps. Acceptance and acceptance tests.
- DSTU EN 809: Pumps and pumping units for liquids. Security requirements.
- Documentation of the pump manufacturer.
