Complete Guide to Fault Diagnosis and Repair of Circulation Oil Pumps: Core Assurance for the Long-term Operation of Industrial Equipment
In the industrial thermal energy system, the circulation oil pump, as the power hub for the forced circulation of thermal oil, directly affects production efficiency and equipment safety. When problems such as abnormal vibration, pressure fluctuations, or leaks occur, scientific fault diagnosis and professional repair are the keys to restoring equipment performance. Combining industry practices, this article systematically analyzes common fault types, repair processes, and maintenance key points of circulation oil pumps, providing enterprises with operational solutions.
I. Common Fault Diagnosis: Pinpointing the Root Causes
1. Leakage Problem
Manifestation: Oil stains on the pump body surface, dropping liquid level, or unstable pressure.
Causes: Aging of seals, improper installation, or loose pipeline connections.
Investigation Method: Observe whether there are oil traces in the sealing area, use a leak detector to detect pressure changes, and focus on checking the wear of the mechanical seal end face (allowable wear amount ≤ 0.5mm).
2. Insufficient Pressure
Manifestation: Slow system temperature rise, abnormal temperature of heat – using equipment.
Causes: Impeller wear, filter clogging, or cavitation in the inlet pipeline.
Diagnostic Steps: Measure the inlet – outlet pressure difference (normal 0.2 – 0.3MPa), check the impurity content of the filter screen (recommended ≤ 0.1%), and observe whether there are cracks or corrosion on the impeller blades.
3. Abnormal Noise and Vibration
Manifestation: Emit harsh noises during operation, with obvious body jitter.
Causes: Damaged bearings, unbalanced impeller, or misaligned coupling.
Detection Means: Use a laser vibration meter to monitor the vibration value (recommended ≤ 5mm/s), check the bearing clearance (rolling bearing clearance 0.02 – 0.04mm), and calibrate the coaxiality of the coupling (deviation ≤ 0.05mm).
II. Standardized Repair Process: Full – cycle Management from Disassembly to Debugging
1. Pre – repair Preparation – Disconnect the power supply and hang a warning sign. Drain the medium in the system and purge the pipeline with nitrogen to prevent contamination by residual oil. – Prepare special tools (such as pullers, torque wrenches), original – factory parts (seals, bearings), and cleaning materials (solvents, compressed air).
2. Inspection and Repair of Core Components
Impeller and Pump Shaft: Check the wear degree of the impeller, measure the shaft bending degree (allowable deviation ≤ 0.05mm). After replacing worn parts, perform dynamic balance correction (residual unbalance amount ≤ 5g).
Sealing System: When replacing the mechanical seal, check the carbon ring and spring components simultaneously. Ensure that the new seal is heat – resistant (above 300°C) and correctly installed.
Bearings and Lubrication: Clean the bearings and apply high – temperature grease (such as ZFG – 4 type). The amount of grease injection is 1/3 of the bearing chamber volume to avoid overheating caused by over – injection.
3. Assembly and Testing
Assemble the pump body in the reverse order of disassembly. Use a torque wrench to tighten the bolts to the specified value (for example, the torque of M12 bolts is 30 – 40N・m). – Manually turn the pump by hand before startup to confirm there is no jamming. Let it run at low speed for 10 – 15 minutes for pre – heating, then gradually load the operation and monitor parameters such as pressure, temperature, and vibration.
III. Key Repair Precautions: Avoiding the Risk of Secondary Failures
1. Safety Operation Specifications
Wear heat – resistant clothing in high – temperature environments to avoid direct contact with hot oil components. – Use anti – static tools in explosion – proof areas to prevent accidents caused by electric sparks.
2. Accessory Selection Standards
Give priority to original – factory parts that match the oil pump model (such as the special seals for the BRY series oil pumps) to ensure that the temperature – resistance and pressure – resistance performance meet the standards. – Replace bearings in pairs to avoid operational imbalance caused by wear differences between new and old parts.
3. Systematic Maintenance Strategies
Clean the filter and heat exchanger simultaneously after repair to remove impurities and prevent blockage. – Establish an equipment repair file to record fault phenomena, repair content, and replaced parts, providing data support for subsequent maintenance.
IV. Preventive Maintenance Suggestions: Extending Equipment Lifecycle
1. Regular Inspection Mechanism
Observe the leakage of the sealing parts daily, supplement bearing grease weekly, and detect the vibration value monthly. – Clean the filter quarterly and conduct a comprehensive inspection of the impeller, shaft, and sealing system annually.
2. Intelligent Monitoring Upgrade
Install temperature/vibration sensors to issue real – time early warnings for abnormal data through the Internet of Things platform (for example, trigger an alarm when the bearing temperature > 80℃). – Adopt variable – frequency speed – regulation technology to automatically adjust the rotation speed according to the load, reducing start – stop impact and saving more than 30% of energy.
Conclusion The repair of circulation oil pumps is not only a process of fault repair but also a key link in improving equipment reliability. Through the combination of accurate diagnosis, standardized repair, and intelligent operation and maintenance, enterprises can significantly reduce downtime risks and extend equipment service life. In the future, with the continuous progress of sealing materials and monitoring technologies, the repair of circulation oil pumps will develop towards a more efficient and intelligent direction, providing a solid guarantee for the stable operation of industrial thermal energy systems.
