Methods to Improve Operation Reliability of Magnetic Seal Pump
Flat Steel,Flat Steel Plate,Flat Bar For Chain,Flat Spring Bar Steel Jiangyin Mitoo Precise Co.,Ltd. , https://www.mitoosteel.com
**I. Introduction**
Our company has recently launched a new production facility with an annual capacity of 40,000 tons of methyl chloride. During the selection of equipment for this project, we conducted extensive research and adhered to an innovative approach. Based on the production process and the properties of the materials being transported, we chose 27 sets of Mihai magnetic pumps. These pumps are manufactured by Dalian Sea Mi Le Sealed Pump Co., Ltd.
The Sea-Mile magnetic pump is designed with advanced technology, featuring a leak-free, maintenance-free structure. It operates as a reliable centrifugal pump with high safety, efficiency, and energy-saving performance. This type of pump is ideal for handling corrosive, toxic, flammable, explosive, expensive, or easily vaporizable liquids. Additionally, it can transport high-temperature, low-temperature fluids and liquids under vacuum conditions. Its complete leak-free design effectively solves common issues such as leakage, dripping, and running in fluid transportation. As a result, it has become an essential component in environmental engineering and is widely used in industries like petrochemicals, refrigeration, air conditioning, and aerospace.
Compared to traditional sealed pumps, the Sea-Mile magnetic pump requires less maintenance, eliminates external lubrication, and reduces vibration and noise. However, due to its unique characteristics, special attention must be given during installation, operation, and maintenance to ensure smooth and reliable performance.
**II. Features of the Sea-Mile Magnetic Pump**
1. **Structure**: The Sea-Mile magnetic pump is a horizontal, completely leak-free centrifugal pump with axial suction and radial discharge. It uses a magnetic coupling to drive the shaft, eliminating the need for a mechanical seal, thus achieving "zero leakage."
2. **Bearings**: The pump's drive shaft is supported by rolling bearings lubricated by internal grease, while the pump shaft is supported by hydraulic sliding bearings.
3. **Magnetic Coupling**: The magnetic coupling is made from high-quality rare-earth permanent magnets, capable of withstanding temperatures up to 350–400°C. This ensures stable and reliable operation, even under high torque conditions. The magnets remain highly stable, preventing damage during assembly or disassembly.
4. **Lubrication and Cooling**: The medium being pumped provides both lubrication and cooling for the sliding bearings, eliminating the need for external systems.
5. **Axial Force Balance**: The pump automatically balances axial forces using hydraulic pressure, which helps protect the bearing during startup and shutdown.
**III. Common Faults and Solutions**
1. **Large Fluctuations in Operating Conditions**: Sudden changes in inlet or outlet pressure can disrupt the hydraulic balance, leading to bearing damage. Proper control of operating parameters is essential.
2. **Cavitation Issues**: Cavitation often occurs due to insufficient inlet flow, gas in the medium, or improper piping design. It can cause severe damage to the impeller, rotor, and bearings.
3. **Low Flow or No Medium**: If the pump runs dry, the sliding bearings may overheat and fail. Ensuring proper flow is crucial for lubrication and cooling.
4. **Isolation Sleeve Damage**: Hard particles in the medium or improper maintenance can scratch or damage the isolation sleeve, leading to potential leaks.
**IV. Ways to Improve Operational Reliability**
1. **Installation Requirements**:
- Ensure the piping system is properly supported to avoid transferring extra loads to the pump.
- Keep the suction piping short to prevent cavitation.
- Install control valves and check valves for better flow regulation.
- Clean all piping thoroughly before commissioning.
- Include a return line with a minimum flow orifice to ensure continuous lubrication.
2. **Process Monitoring**:
- Use level sensors to protect against dry running.
- Monitor pump temperature to detect early signs of failure.
- Install differential pressure sensors to detect abnormal conditions.
- Maintain proper flow and head within the pump’s performance curve.
- Ensure sufficient net positive suction head (NPSH) to prevent cavitation.
3. **Operational Procedures**:
- Fully prime and vent the pump before starting.
- Follow a proper start-up sequence: open the inlet valve, close the outlet, start the motor, and gradually open the outlet valve.
- Ensure the pump operates within its specified range.
**V. Operation and Maintenance Notes**
1. Never operate the pump without liquid or with the outlet valve closed, as this can damage the bearings.
2. Ensure synchronization between the pump and motor. If the pump fails, it may indicate that the magnetic coupling is overloaded.
3. Unusual vibration or increased noise may signal bearing wear. Check lubrication levels regularly.
4. The rolling bearings are permanently lubricated, but periodic inspections and replacements are necessary.
5. A failed magnetic coupling does not necessarily mean the magnet is damaged; it could be due to poor bearing lubrication.
6. Handle the magnetic components carefully during maintenance to avoid interference with electronic devices.
7. If the pump is not in use for long periods, flush it with the appropriate fluid to prevent crystallization or solidification of the medium.