What are the methods your factory uses for the maintenance of centrifugal pumps?
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What methods does your factory use for the maintenance of centrifugal pumps?
Chapter 6 Operation Management of Mechanical Pumps Article 23: Before starting a mechanical pump, the instruments, meters, and auxiliary equipment related to it (such as the cooling water system, seal oil system, forced lubrication system, pump protection system, pressure gauges, thermometers, shaft seal pumps, etc.) must be complete and in good condition. Sufficient quantities of qualified lubricating oil must be ensured at all lubrication points, the \"five fixings\" and \"three-stage filtration\" principles must be followed, and the relevant equipment lubrication procedures must be strictly implemented. The five fixes: fixing the person, the location, the time, the quality, and the quantity. Third-level filtration: from the large oil storage tank to the on-site oil storage tank (60 mesh), from the on-site oil storage tank to the oil jug (80 mesh), and from the oil jug to the fueling point (100 mesh). Article 24: During the operation of the pump, relevant personnel shall conduct regular inspections. (1) Timing: Operators conduct inspections every two hours; the equipment staff in the workshop carry out inspections daily; those responsible for maintenance workshops and electrical workshops conduct inspections twice a day. (2) Inspection contents: Check changes in parameters such as pump flow, pressure, and current; examine bearing temperature and vibration levels; check for seal leaks; verify that the cooling and lubrication systems are functioning properly. (3) In case of any abnormalities detected during inspections, it is necessary to determine the cause, address it promptly, and keep records of it. Article 25: Regarding the requirements for the temperature, vibration, and leakage of pump bearings, unless specified by the pump manufacturer, the following rules shall apply:
**Electric motors:**
- **Temperature:** Sliding bearings – not more than 80°C; Rolling bearings – not more than 100°C.
- **Vibration:** At a speed of ≤3000 revolutions per minute, the amplitude shall be ≤0.06 mm; at a speed of ≤1500 revolutions per minute, the amplitude shall be ≤0.10 mm; at a speed of ≤1000 revolutions per minute, the amplitude shall be ≤0.13 mm; at a speed of ≤750 revolutions per minute, the amplitude shall be ≤0.16 mm.
**Pumps:**
- **Temperature:** Sliding bearings – not more than 65°C; Rolling bearings – not more than 70°C.
- **Vibration:** At a speed of ≤3000 revolutions per minute, the amplitude shall be ≤0.06 mm; at a speed of ≤1500 revolutions per minute, the amplitude shall be ≤0.10 mm.
- **Leakage:**
- For mechanical seals: With light oils and water, the leakage shall be no more than 6 drops per minute; with heavy oils, it shall be no more than 3 drops per minute. With liquid hydrocarbons, there shall be no visible leakage or the leakage shall be within the pressure alarm threshold.
- For packing seals: With light oils and water, the leakage shall be no more than 10 drops per minute; with heavy oils, it shall be no more than 6 drops per minute.
The vibration requirements shall also comply with the ISO 2372 vibration standard (Appendix 1). Article 26: For pumps equipped with inlet filters, the user entity shall determine a cleaning schedule based on changes in the pump’s pressure and flow rate, and clean the filters regularly. Article 27: After stopping the centrifugal pump, turn the rotor 3–5 times and check whether it rotates smoothly, as well as for any abnormalities such as uneven weight distribution. When the hot oil pump is shut down for cooling, turn the shaft every 10 minutes until the cooling process is normal. During the cooling process of the hot oil pump, the cooling water and seal oil must not be turned off; it is only possible to stop them once the temperature of the pump body drops to room temperature. Article 28: During the anti-corrosion painting of the pump casing, it is strictly prohibited to paint areas such as the equipment nameplate, the bolts on the cover, and the couplings. On the side of the motor, the coupling should be painted half red and half white as a mark for turning the shaft. Article 29: During the operation of pumps, a regular switching system must be strictly implemented, with a switching cycle of three months ； The drive units are high-pressure motors and pumps that are difficult to switch, which can lead to fluctuations in production; the switching cycle is six months. In cases where switching proves difficult during production, it is carried out according to the production schedule. Article 30: For standby pumps (except shielded pumps), a regular turning-over procedure must be strictly followed, and records must be kept. Regular turning: Turn the shaft 180° per day and keep records of the turning. White on single days, red on double days. Article 31: The operators of pumps in each workshop are the main persons responsible for their maintenance. They must strictly follow the equipment operation procedures and carry out proper maintenance work on the pumps to ensure their safe operation.
**Electric motors:**
- **Temperature:** Sliding bearings – not more than 80°C; Rolling bearings – not more than 100°C.
- **Vibration:** At a speed of ≤3000 revolutions per minute, the amplitude shall be ≤0.06 mm; at a speed of ≤1500 revolutions per minute, the amplitude shall be ≤0.10 mm; at a speed of ≤1000 revolutions per minute, the amplitude shall be ≤0.13 mm; at a speed of ≤750 revolutions per minute, the amplitude shall be ≤0.16 mm.
**Pumps:**
- **Temperature:** Sliding bearings – not more than 65°C; Rolling bearings – not more than 70°C.
- **Vibration:** At a speed of ≤3000 revolutions per minute, the amplitude shall be ≤0.06 mm; at a speed of ≤1500 revolutions per minute, the amplitude shall be ≤0.10 mm.
- **Leakage:**
- For mechanical seals: With light oils and water, the leakage shall be no more than 6 drops per minute; with heavy oils, it shall be no more than 3 drops per minute. With liquid hydrocarbons, there shall be no visible leakage or the leakage shall be within the pressure alarm threshold.
- For packing seals: With light oils and water, the leakage shall be no more than 10 drops per minute; with heavy oils, it shall be no more than 6 drops per minute.
The vibration requirements shall also comply with the ISO 2372 vibration standard (Appendix 1). Article 26: For pumps equipped with inlet filters, the user entity shall determine a cleaning schedule based on changes in the pump’s pressure and flow rate, and clean the filters regularly. Article 27: After stopping the centrifugal pump, turn the rotor 3–5 times and check whether it rotates smoothly, as well as for any abnormalities such as uneven weight distribution. When the hot oil pump is shut down for cooling, turn the shaft every 10 minutes until the cooling process is normal. During the cooling process of the hot oil pump, the cooling water and seal oil must not be turned off; it is only possible to stop them once the temperature of the pump body drops to room temperature. Article 28: During the anti-corrosion painting of the pump casing, it is strictly prohibited to paint areas such as the equipment nameplate, the bolts on the cover, and the couplings. On the side of the motor, the coupling should be painted half red and half white as a mark for turning the shaft. Article 29: During the operation of pumps, a regular switching system must be strictly implemented, with a switching cycle of three months ； The drive units are high-pressure motors and pumps that are difficult to switch, which can lead to fluctuations in production; the switching cycle is six months. In cases where switching proves difficult during production, it is carried out according to the production schedule. Article 30: For standby pumps (except shielded pumps), a regular turning-over procedure must be strictly followed, and records must be kept. Regular turning: Turn the shaft 180° per day and keep records of the turning. White on single days, red on double days. Article 31: The operators of pumps in each workshop are the main persons responsible for their maintenance. They must strictly follow the equipment operation procedures and carry out proper maintenance work on the pumps to ensure their safe operation.
Check the lubricating oil; address any low or high oil levels promptly, and change the oil immediately if emulsification is detected； Check whether the fasteners are loose, and address any looseness promptly.