Request operating procedures for individual equipment
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How to write operating procedures for individual equipment. Last edited by brainandrain on 2009-2-12 20:26 in this post.]
It’s too general; I can’t figure out what you actually want. I suggest you read the detailed rules carefully again
Which individual devices are they? Please be more specific
Table of Contents 1 General Provisions 2 1.1 Scope of Application 2 1.2 Brief Structure Description 2 1.3 Technical Performance 2 2 Integrity Standards 2 2.1 Parts and Components 3 2.2 Operational Performance 3 2.3 Technical Documentation 3 2.4 Equipment and Environment 3 3 Equipment Maintenance 3 3.1 Routine Maintenance 3 3.2 Regular Inspection Items 3 3.3 Methods for Handling Common Faults 3 3.4 Emergency Shutdown 3 4 Inspection and Maintenance Periods and Contents 4 4.1 Inspection Periods 4 4.2 Maintenance Contents 4 5 Maintenance Methods and Quality Standards 5 5.1 Pump Body and Base 5 5.2 Pump Shaft and Sleeve 5 5.3 Impeller 5 5.4 Disassembly and Assembly of the Rotor Part 5 5.5 Rolling Bearings 7 5.6 Sliding Bearings 7 5.7 Sealing Devices 7 5.8 Couplings 8 6 Commissioning and Acceptance 8 6.1 Preparatory Work Before Commissioning 8 6.2 Commissioning 8 6.3 Acceptance 8 7 Safety Precautions for Maintenance and Repair 8 7.1 Safety Precautions for Maintenance 8 7.2 Safety Precautions for Repair 8 7.3 Safety Precautions for Commissioning 8 1 General Provisions 1.1 Scope of Application These regulations apply to the maintenance and repair of single-stage, single-suction and single-stage, double-suction centrifugal pumps with an inlet diameter of less than 600 mm and models IS, IH, and Sh used in chemical enterprises. It can also be used for the maintenance and repair of BA-type and F-type centrifugal pumps. Other similar types of pumps can be used as a reference. 1.2 Brief structure description A single-stage centrifugal pump is mainly composed of components such as the pump body, pump cover, impeller, shaft, and bracket. The impeller of a single-suction pump is mounted at the shaft end in a cantilever configuration; water enters at the axial end face, while the discharge outlet is perpendicular to the pump’s axis. The pump body of the double-suction pump is of horizontal split type; it features a double-suction impeller, which is supported by bearings at both ends. The inlet and outlet are located on the pump body and are horizontal, perpendicular to the pump body. The motor drives the pump directly through a coupling. 1.3 Technical Performance 1.3.1 The main performance parameters of IS and IH type single-stage, single-suction centrifugal pumps are shown in Table 1. Table 1: Liquids to be transported – Clean water and liquids with physical and chemical properties similar to water, with a maximum temperature of 80°C. 2. Integrity criteria 2.1 Components and parts 2.1.1 The pump body and all its components and parts must be intact and complete. 2.1.2 The foundation bolts and all connection bolts are complete and properly tightened. 2.1.3 Safety protection devices are complete and secure. 2.1.4 Gauges such as pressure gauges and ammeters are complete, sensitive, have ranges that meet the specified requirements, and are calibrated regularly. 2.1.5 The installation coordination of various components complies with the regulations. 2.1.6 The pump body, as well as the associated valves, fittings, and pipelines, are properly painted with clear markings. 2. 1.7 The foundation and base are complete and sturdy. 2.2 Operational Performance 2.2.1 The oil circuit is unobstructed and the lubrication is optimal; the \"five fixed principles\" and \"three-stage filtration\" are implemented. 2.2.2 It is operating normally, with no abnormal vibrations or noises. 2.2.3 Pressure and flow are stable, temperatures in all sections are normal, and current is stable. 2.2.4 It can achieve the output specified on the nameplate or the rated capacity. 2.3 Technical documents 2.3.1 General layout or structural diagram of the pump, as well as diagrams of wear-prone parts. 2.3.2 It comes with an instruction manual, a product certificate of conformity, and a quality certificate. 2.3.3 Complete set of operating procedures and maintenance regulations. 2.3.4 The equipment records are complete, and the data is accurate and reliable, including: a. Installation and commissioning acceptance documents ； b. Equipment operation records ； c. Records of previous inspections and acceptances ； d. Records of equipment defects and accident occurrences. 2.4 Equipment and Environment 2.4.1 The equipment should be clean, with no dust or oil residue on its surface. 2.4.2 The foundation and base are clean; there is no water accumulation or waste liquid on their surfaces or around them, and the environment is tidy and clean. 2.4.3 There are no leaks at the joints of the inlet and outlet valves, pipe flanges, pump bodies, etc. 2.4.4 Leakage at the shaft seal a. Packing seal: When the medium is water, the leakage rate should not exceed 20 drops per minute in the initial stage, and no more than 40 drops per minute in the final stage ； Other liquids, no more than 15 drops per minute ； b. Mechanical seal: There should be no leakage at the beginning, and no more than 5 drops per minute at the end. 3. Equipment maintenance 3.1 Routine maintenance 3.1.1 Start, operate, and shut down the equipment in strict accordance with the operating procedures, and keep proper operation records. 3.1.2 Check the lubrication of all lubricated parts at the beginning of each shift. 3.1.3 After installing new bearings, the equipment should be cleaned and its oil changed after 100 hours of operation ； In the future, change the oil every 1,000–1,500 hours of operation, and change the grease every 2,000–2,400 hours of operation. 3.1.4 Regularly check the bearing temperature; it should not be higher than the ambient temperature by 35℃ ； Maximum temperature of bearings: Rolling bearings shall not exceed 75°C, and sliding bearings shall not exceed 65°C. 3.1.5 Regularly check whether the pump pressure and motor current are normal and stable, and whether there are any abnormal noises or vibrations during equipment operation; address any issues that arise promptly. 3.1.6 Keep the pump and its surrounding area clean at all times, and promptly eliminate any leaks or spills. The sealing meets the requirements. 3.1.7 Maintenance personnel should be on duty at regular intervals to inspect the equipment and address any issues detected promptly. 3.1.8 When the pump is not in use and the ambient temperature is low, drain any remaining liquid to prevent the casing and components from freezing and cracking. 3.2 Regular inspection items For important pumps in the production system, regular inspections can be carried out according to the contents in Table 3. 3.3 Common Fault Handling Methods The common fault handling methods are shown in Table 4. 3.4 Emergency shutdown In any of the following situations, an emergency shutdown should be carried out: a. Abnormal noises are heard from the pump ； b. The pump suddenly experiences severe vibration ； c. The motor current exceeds the rated value and remains high without decreasing ； d. The pump suddenly stops pumping water. Table 3 Inspection Items, Cycle, Content, Judgment Criteria, Recommended Instruments
Monitoring of rolling shafts: To check operating conditions; measure the impact energy of vibration in rolling bearings to determine whether they are in good condition.
- When dBN < 20, the bearing is in good condition; measure again according to the scheduled cycle.
- When 20 < dBN < 35, attention is required; early damage has occurred in the bearing, and it must be measured again within a short period.
- When dBN > 35, the bearing has significant damage, and measurement must be carried out even sooner.
- When dBN > 50, the bearing should be replaced promptly.
Impact pulse meter: The single-amplitude A should not exceed the following values:
1) When the axis centerline height ≤ 225 mm:
- At rotation speed n = 1450 r/min, A ≤ 0.03 mm
- At rotation speed n = 2900 r/min, A ≤ 0.02 mm
2) When the axis centerline height > 225 mm:
- At rotation speed n = 970 r/min, A ≤ 0.06 mm
- At rotation speed n = 1450 r/min, A ≤ 0.04 mm
- At rotation speed n = 2900 r/min, A ≤ 0.03 mm
Portable vibration meter
Table 4 Phenomena, Causes, Treatment Methods
Phenomena, Causes, Treatment Methods
Pump does not deliver water or flow rate is insufficient:
1. Clogged suction valve
2. Excessive resistance in the suction pipeline or too high water intake height
3. Excessive resistance in the discharge pipeline
4. Air present in the pump or suction pipe, with leaks
5. Clogged impeller
6. Severely worn sealing ring
1. Clean the suction valve
2. Clean the suction pipeline or lower the water intake height
3. Inspect and clean the discharge pipeline or improve it
4. Remove air and fix leaks
5. Clean the impeller
6. Replace the impeller sealing ring
Abnormal noise inside the pump, pump does not supply water:
1. Excessive flow rate
2. Excessive resistance in the suction pipe
3. Air infiltration in the suction pipe section
4. Excessively high temperature of the liquid being pumped
1. Increase the flow rate
2. Clean the suction pipe or lower the suction height
3. Inspect the suction pipe section and valves to eliminate leaks
4. Lower the temperature of the liquid being pumped
High bearing temperature:
1. Insufficient oil quantity or dirty oil
2. Too small bearing clearance
3. The coaxiality between the motor shaft and the pump shaft exceeds the specified value
1. Add oil or clean the bearings and change the oil
2. Lube the bearing bushes and adjust...
Excessive current:
1. Packing pressed too tightly
2. Friction between the rotating part and the fixed part
3. Excessive flow volume
1. Loosen the packing gland
2. Inspect and adjust
3. Reduce the flow rate by adjusting the outlet valve
4. Align the coupling
Severe leakage at the seal:
1. Worn packing
2. Worn shaft or sleeve
3. Bent pump shaft
4. Corrosion, wear, or scratches on the end surfaces of the dynamic and static sealing rings
5. Misaligned installation of the static ring
6. Insufficient spring pressure
1. Replace the packing
Excessive pump vibration:
1. The coaxiality between the motor shaft and the pump shaft exceeds the specified value
2. Bent pump shaft or unbalanced rotor
3. Foreign objects in the impeller or worn impeller
4. Friction between the rotor and the casing
5. Large bearing clearance
6. Loose base bolts
1. Align the coupling
2. Straighten the shaft and rotor and balance them
3. Clean the impeller or replace it
4. Adjust the clearance between the rotor and the casing
5. Adjust the clearance or replace the bearings
6. Tighten the base bolts
2. Repair or replace worn parts
3. Rectify or replace the pump shaft
4. Repair or replace the dynamic and static sealing rings
5. Reinstall the static ring
6. Adjust the spring compression or replace the spring
4. Maintenance Cycle and Contents
4.1 Maintenance Cycle
The maintenance cycle is shown in Table 5. Table 5 Maintenance Types: Minor Repair, Medium Repair, Major Repair; Maintenance Cycle, in months: 3, 12–24, 36. Note: 1. Pumps with an inlet diameter of ≤100 mm do not require major repair; the tasks associated with major repair are included in the medium repair. 2. When the unit’s condition monitoring capabilities enable predictive maintenance, with the approval of the higher-level supervising authority, it may be exempt from the requirements of this table. 4.2 Maintenance Tasks 4.2.1 Minor Repairs 4.2.1.1 Inspect the packing seal and replace the packing. 4.2.1.2 Check and adjust the coaxiality and axial clearance of the coupling, and replace its vulnerable components. 4.2.2.3 Disassemble and inspect the wear, corrosion, and erosion of each component, and repair or replace them as necessary. 4.2.2.4 Check the shaft for wear, corrosion, and straightness, and carry out repairs. 4.2.2.5 Determine the static balance of the impeller and check the rotor’s runout. 4.2.2.6 Check the wear condition of the bearings, lap the bearing shells, adjust the clearance, and replace the bearings. 4.2.2.7 Check and adjust the clearances of various components such as the impeller seal ring, shaft sleeve, gland, and shaft seal. 4.2.2.8 Check or calibrate the pressure gauge. 4.2.2.9 Inspect, clean, and repair the motor. 4.2.3 Major Overhaul 4.2.3.1 includes the contents of the medium overhaul. 4.2.3.2 Replace the impeller. 4.2.3.3 Replace the pump shaft. 4.2.3.4 Pump body thickness measurement and inspection ； Make the necessary repairs. 4.2.3.5 Measure and adjust the levelness of the pump body. 4.2.3.6 Rust removal and corrosion protection. 5. Maintenance methods and quality standards 5.1 Pump body and base 5.1.1 The pump body and base shall be free of cracks; the casting surfaces of the vortex chamber and liquid flow channels in the pump body shall be smooth. When cracks or other casting defects that can be repaired by welding are found in areas not subject to pressure, repairs shall be carried out in accordance with JB/TQ369 \"Welding Repair of Cast Iron Parts for Pumps\". 5.1.2 The flatness of the mid-surface between the pump casing and the pump cover of a double-suction impeller pump should not exceed 0.1 mm when checked with a 1-meter-long straight edge; paper shims with a thickness of 0.2–0.25 mm should be used during assembly. 5.1.3 Levelness of pump body installation: a. Single-suction centrifugal pump: longitudinally (along the pump shaft direction) 0.05 mm/m ； Transverse (perpendicular to the pump shaft direction): 0.10 mm/m. b. Double-suction centrifugal pump: 0.05 m/m in both the longitudinal and transverse directions. 5.2 Pump shaft and shaft sleeve 5.2.1 The pump shaft shall be free from defects such as corrosion or cracks; when it is necessary to repair or replace the pump shaft, non-destructive testing can be carried out to check for any cracks. 5.2.2 Surface roughness of the pump shaft journals: 3.2 at the locations where the impeller, shaft sleeves, and couplings are installed; 1.6 at the locations where rolling bearings are installed; 0.8 for sliding bearings. 5.2.3 Using the journals at the two bearings as supports, a dial indicator should be used to check the radial runout of the journals at locations such as those where the impeller, shaft sleeves, and couplings are installed; this value should not exceed 0.03 mm. 5.2.4 The offset of the keyway center from the journal centerline shall not exceed 0.06 mm, and the skew shall not exceed 0.03 mm/100 mm. 5.2.5 After keyway wear, it can be increased appropriately depending on the degree of wear; however, the maximum increase is one size level above the standard dimension. When the structure and load conditions permit, additional keyways can be created at 90° or 120° to the original keyway. 5.2.6 After wear of the shaft journal, it can be repaired by electroplating, spraying, or coating. 5.2.7 The bushing material shall comply with the drawings ； The shaft sleeve must be free of cracks, and its outer circular surface must not have any casting defects such as sand holes, pores, or porosity. 5.2.8 The fit between the bushing and the shaft is H8/h8 or H9/h9. 5.3 Rotor 5.3.1 The surface of the rotor and the inner walls of the fluid flow channels must be kept clean; there should be no sand adhesion, burrs, or dirt ； The junction between the machined surface and the unmachined surface at the inlet of the flow channel should have a smooth transition. 5.3.2 The impeller and shaft generally use an H7/h6 fit. 5.3.3 The newly installed impeller must be statically balanced, and the unbalanced weight resulting from this balancing process shall not exceed the values specified in Table 6 ； When exceeded, deburring should be performed by cutting from both sides of the impeller; the thickness removed shall not exceed 1/3 of the original wall thickness of the impeller, and the cut area shall meet smoothly with the uncut area. 5.4 Disassembly and assembly of the rotor section 5.4.1 When removing components such as shaft sleeves, impeller nuts, and rolling bearings, if they are stuck due to rust, soak them in kerosene or a rust remover before attempting to remove them; do not strike them forcefully. 5.4.2 After assembly, the radial runout of the outer surface of the seal area on the impeller and the outer surface of the shaft sleeve shall not exceed the values specified in Table 7. Table 6: Outer diameter of the rotor, in mm – ≤ 200, 201–300, 301–400, 401–500, 501–700, 701–900. Allowable unbalance weight, in g: 3, 5, 6, 10, 15, 20. 5.4.3 The diameter clearance between the outer surface of the rotor’s sealing area and the sealing ring is specified in the drawings; if no such data are available, values can be selected from Tables 8 to 10. Among them: Table 8 applies to pumps made of cast iron and bronze ； Table 9 applies to pumps made of carbon steel and Crl3 steel ； Table 10 applies to pumps made of 1Cr18N19 or similar acid-resistant steels. The gaps around should be even. 5.5 Rolling Bearings 5.5.1 The rollers and raceways of rolling bearings should be free from defects such as pits and rust spots; the retainers must be in good condition, the contact surface should be smooth, and there should be no abnormal noises during rotation. 5.5.2 The dimensions of the shaft journal that mates with the rolling bearing and the bearing housing shall comply with the specifications in the drawings. 5.5.3 The gap between the shaft pressure cover and the end face of the rolling bearing shall not be greater than 0.10 mm ； The clearance between the bearing cover on the expanded side of the shaft and the end face of the rolling bearing should be determined based on the length of the shaft between the two bearings and the temperature of the medium, ensuring an adequate amount of clearance is provided. 5.5.4 Special mounting and removal tools or a press should be used for mounting and removing rolling bearings, and the method must be correct. Do not strike the bearing directly with a hammer. After assembly, the end face of the bearing inner ring should be in close contact with the shaft shoulder. 5.5.5 When installing bearings on shaft journals by heating, they should be heated in engine oil at a temperature not exceeding 120°C or using a bearing heater; direct flame heating is strictly prohibited. 5.6 Sliding bearings 5.6.1 The bond between the bearing alloy and the bearing shell should be tight and secure, with no pores or defects on the surface. 5.6: The contact angle between 2 and the journal is in the range of 60°–90° at the middle part of the lower bearing shell (the lower limit applies when the rotation speed is >1000 r/min, while the upper limit applies when the rotation speed is <1000 r/min). The contact is even; when checked using the coloring method, there should be 2–4 color spots per square centimeter. 5.6.3 The top clearance of the bearing shells shall be selected according to Table 11. 5.7 Sealing Devices 5.7.1 Packing Seals 5.7.1.1 The surface roughness of the shaft sleeve (or shaft) at the packing box shall not exceed a certain value. 5.7.1.2 The diameter clearance between the packing sleeve and gland, as well as the shaft sleeve (or shaft), shall be selected according to the table provided; the clearances around the perimeter should be uniform. 5.7.1.3 The fit between the packing gland and the inner wall of the packing box is H11/d11. 5.7.1.4 The diameter clearance between the packing ring and the inner wall of the packing box is 0.15–0.20 mm; the diameter clearance between the packing ring and the shaft sleeve (or shaft) should be increased by 0.3–0.5 mm compared to the values given in Table 12. 5.7.1.5 The depth to which the gland is pressed into the packing box should be 0.5–1 turn of the packing height, with a minimum of 5 mm; the gland must not be skewed, and its tightness must be adjusted appropriately. 5.7.1.6 The packing joints should be butted at an angle, and the appropriate type of packing should be selected. 5.7.1.7 Ensure that the groove of the packing ring is aligned with the water seal hole on the packing box or slightly to the outside, so as to allow smooth water flow. 5.7.2 Mechanical Seals 5.7.2.1 Requirements for the shaft (or shaft sleeve) at the location where the mechanical seal is installed: a. The radial runout shall meet the specifications given in Table 7 ； b. Surface roughness ； c. The outer diameter deviation shall not exceed h6. 5.7.2.2 The axial play of the pump shaft shall not exceed ±0.5mm. 5.7.2.3 The flatness of the sealing surface where the moving ring meets the stationary ring must meet the required standards, and the surface roughness should be as specified for metal material sealing rings, and as specified for non-metal material sealing rings. The surface roughness at the contact points between the rotating ring, the stationary ring, and the auxiliary sealing ring should be. 5.7.2.4 Disassembly and assembly of mechanical seals a. Disassembly and assembly must be carried out carefully to avoid knocking or scratching the sealing surfaces of the moving and stationary rings as well as the auxiliary sealing rings; it is absolutely not allowed to use hammers or iron tools for striking ； b. During installation, the assembly area and mechanical seal must be cleaned thoroughly to prevent any impurities from entering the sealing area. The sealed cover can be coated with turbine oil or spindle oil during assembly ； ’ c. The compression amount of the spring must be appropriate, so that its length after compression is its operating length. 5.8 Couplings: The alignment deviation and end-face clearance of the two shafts in an elastic sleeve pin coupling shall comply with the standards specified in Table 13 below. 6. Commissioning and Acceptance 6.1 Preparations before commissioning 6.1.1 Remove all debris from the pump base and its surrounding area, and clean the site properly. 6.1.2 Check the tightness of the bolts for the pump base, motor base, and all connection bolts. 6.1.3 Check whether the seal meets the requirements and whether the cooling system is unobstructed. 6.1.4 Apply lubricant (grease) as specified. 6.1.5 For the idling motor, check the rotation direction; once it is correct, install the coupling pin. 6.2 Commissioning 6.2.1 Rotate the pump for two weeks, paying attention to any abnormal noises inside the pump and whether the rotation is smooth; reinstall the protective cover after rotation. 6.2.2 Introduce or fill the pump with liquid and remove air. 6.2.3 Start the pump in accordance with the starting procedure; once it operates normally after startup, continuous operation for testing can proceed. 6.2.4 The testing time shall be no less than 2 hours, and the following shall be achieved: a. Smooth operation without abnormal noises, with proper cooling and lubrication ； b. Bearing temperature is normal ； c. The vibration of the housing at the bearing area shall not exceed the specified limits ； d. The flow rate and head reach the values specified on the nameplate or the rated capacity ； The motor current does not exceed the rated value ； e. The sealing meets the requirements. 6.3 Acceptance: If the quality of the pump after maintenance meets the requirements of these regulations, if the maintenance records are complete and accurate, and if the trial operation proceeds smoothly, then acceptance can be carried out in accordance with the relevant procedures. 7 Safety Precautions for Maintenance and Repair 7.1 Safety Precautions for Maintenance 7.1.1 No maintenance tools or any objects shall be placed on the pump base. 7.1.2 Do not wipe the equipment near the rotating parts while the pump is in operation. 7.1.3 Keep the motor grounding wire in good condition, and be careful not to spray water on the motor during cleaning. 7.2 Safety Precautions for Maintenance 7.2.1 Maintenance personnel shall comply with the safety operating procedures specific to their job, as well as the company’s relevant regulations regarding safe maintenance work. 7.2.2 Relevant safety maintenance procedures must be carried out before maintenance. 7.2.3 Turn off the power supply and hang a “Do Not Operate” sign. 7.2.4 Drain the remaining liquid, close the inlet and outlet valves, or install blind flanges to isolate the system. 7.2.5 The removed, cleaned, and replaced parts, as well as the maintenance tools, should be neatly arranged to ensure orderly maintenance work. 7.3 Safety Precautions for Testing 7.3.1 Testing should be carried out in an organized manner, with a dedicated person responsible for ensuring safety during the testing process. 7.3.2 Pump start-up and shutdown shall be carried out by designated personnel, who must hold the \"Safety Operation Certificate\" for that position. 7.3.3 Start and stop the pump strictly in accordance with the operating procedures for starting and stopping the pump. 7.3.4 If abnormal noises or other irregularities are detected during testing, the machine should be stopped to investigate the cause; it must be resolved before attempting to continue testing. Is it this one? If it’s incorrect, please write in more detail. This post was last edited by lxzzl on 2009-2-19 16:04.]
Monitoring of rolling shafts: To check operating conditions; measure the impact energy of vibration in rolling bearings to determine whether they are in good condition.
- When dBN < 20, the bearing is in good condition; measure again according to the scheduled cycle.
- When 20 < dBN < 35, attention is required; early damage has occurred in the bearing, and it must be measured again within a short period.
- When dBN > 35, the bearing has significant damage, and measurement must be carried out even sooner.
- When dBN > 50, the bearing should be replaced promptly.
Impact pulse meter: The single-amplitude A should not exceed the following values:
1) When the axis centerline height ≤ 225 mm:
- At rotation speed n = 1450 r/min, A ≤ 0.03 mm
- At rotation speed n = 2900 r/min, A ≤ 0.02 mm
2) When the axis centerline height > 225 mm:
- At rotation speed n = 970 r/min, A ≤ 0.06 mm
- At rotation speed n = 1450 r/min, A ≤ 0.04 mm
- At rotation speed n = 2900 r/min, A ≤ 0.03 mm
Portable vibration meter
Table 4 Phenomena, Causes, Treatment Methods
Phenomena, Causes, Treatment Methods
Pump does not deliver water or flow rate is insufficient:
1. Clogged suction valve
2. Excessive resistance in the suction pipeline or too high water intake height
3. Excessive resistance in the discharge pipeline
4. Air present in the pump or suction pipe, with leaks
5. Clogged impeller
6. Severely worn sealing ring
1. Clean the suction valve
2. Clean the suction pipeline or lower the water intake height
3. Inspect and clean the discharge pipeline or improve it
4. Remove air and fix leaks
5. Clean the impeller
6. Replace the impeller sealing ring
Abnormal noise inside the pump, pump does not supply water:
1. Excessive flow rate
2. Excessive resistance in the suction pipe
3. Air infiltration in the suction pipe section
4. Excessively high temperature of the liquid being pumped
1. Increase the flow rate
2. Clean the suction pipe or lower the suction height
3. Inspect the suction pipe section and valves to eliminate leaks
4. Lower the temperature of the liquid being pumped
High bearing temperature:
1. Insufficient oil quantity or dirty oil
2. Too small bearing clearance
3. The coaxiality between the motor shaft and the pump shaft exceeds the specified value
1. Add oil or clean the bearings and change the oil
2. Lube the bearing bushes and adjust...
Excessive current:
1. Packing pressed too tightly
2. Friction between the rotating part and the fixed part
3. Excessive flow volume
1. Loosen the packing gland
2. Inspect and adjust
3. Reduce the flow rate by adjusting the outlet valve
4. Align the coupling
Severe leakage at the seal:
1. Worn packing
2. Worn shaft or sleeve
3. Bent pump shaft
4. Corrosion, wear, or scratches on the end surfaces of the dynamic and static sealing rings
5. Misaligned installation of the static ring
6. Insufficient spring pressure
1. Replace the packing
Excessive pump vibration:
1. The coaxiality between the motor shaft and the pump shaft exceeds the specified value
2. Bent pump shaft or unbalanced rotor
3. Foreign objects in the impeller or worn impeller
4. Friction between the rotor and the casing
5. Large bearing clearance
6. Loose base bolts
1. Align the coupling
2. Straighten the shaft and rotor and balance them
3. Clean the impeller or replace it
4. Adjust the clearance between the rotor and the casing
5. Adjust the clearance or replace the bearings
6. Tighten the base bolts
2. Repair or replace worn parts
3. Rectify or replace the pump shaft
4. Repair or replace the dynamic and static sealing rings
5. Reinstall the static ring
6. Adjust the spring compression or replace the spring
4. Maintenance Cycle and Contents
4.1 Maintenance Cycle
The maintenance cycle is shown in Table 5. Table 5 Maintenance Types: Minor Repair, Medium Repair, Major Repair; Maintenance Cycle, in months: 3, 12–24, 36. Note: 1. Pumps with an inlet diameter of ≤100 mm do not require major repair; the tasks associated with major repair are included in the medium repair. 2. When the unit’s condition monitoring capabilities enable predictive maintenance, with the approval of the higher-level supervising authority, it may be exempt from the requirements of this table. 4.2 Maintenance Tasks 4.2.1 Minor Repairs 4.2.1.1 Inspect the packing seal and replace the packing. 4.2.1.2 Check and adjust the coaxiality and axial clearance of the coupling, and replace its vulnerable components. 4.2.2.3 Disassemble and inspect the wear, corrosion, and erosion of each component, and repair or replace them as necessary. 4.2.2.4 Check the shaft for wear, corrosion, and straightness, and carry out repairs. 4.2.2.5 Determine the static balance of the impeller and check the rotor’s runout. 4.2.2.6 Check the wear condition of the bearings, lap the bearing shells, adjust the clearance, and replace the bearings. 4.2.2.7 Check and adjust the clearances of various components such as the impeller seal ring, shaft sleeve, gland, and shaft seal. 4.2.2.8 Check or calibrate the pressure gauge. 4.2.2.9 Inspect, clean, and repair the motor. 4.2.3 Major Overhaul 4.2.3.1 includes the contents of the medium overhaul. 4.2.3.2 Replace the impeller. 4.2.3.3 Replace the pump shaft. 4.2.3.4 Pump body thickness measurement and inspection ； Make the necessary repairs. 4.2.3.5 Measure and adjust the levelness of the pump body. 4.2.3.6 Rust removal and corrosion protection. 5. Maintenance methods and quality standards 5.1 Pump body and base 5.1.1 The pump body and base shall be free of cracks; the casting surfaces of the vortex chamber and liquid flow channels in the pump body shall be smooth. When cracks or other casting defects that can be repaired by welding are found in areas not subject to pressure, repairs shall be carried out in accordance with JB/TQ369 \"Welding Repair of Cast Iron Parts for Pumps\". 5.1.2 The flatness of the mid-surface between the pump casing and the pump cover of a double-suction impeller pump should not exceed 0.1 mm when checked with a 1-meter-long straight edge; paper shims with a thickness of 0.2–0.25 mm should be used during assembly. 5.1.3 Levelness of pump body installation: a. Single-suction centrifugal pump: longitudinally (along the pump shaft direction) 0.05 mm/m ； Transverse (perpendicular to the pump shaft direction): 0.10 mm/m. b. Double-suction centrifugal pump: 0.05 m/m in both the longitudinal and transverse directions. 5.2 Pump shaft and shaft sleeve 5.2.1 The pump shaft shall be free from defects such as corrosion or cracks; when it is necessary to repair or replace the pump shaft, non-destructive testing can be carried out to check for any cracks. 5.2.2 Surface roughness of the pump shaft journals: 3.2 at the locations where the impeller, shaft sleeves, and couplings are installed; 1.6 at the locations where rolling bearings are installed; 0.8 for sliding bearings. 5.2.3 Using the journals at the two bearings as supports, a dial indicator should be used to check the radial runout of the journals at locations such as those where the impeller, shaft sleeves, and couplings are installed; this value should not exceed 0.03 mm. 5.2.4 The offset of the keyway center from the journal centerline shall not exceed 0.06 mm, and the skew shall not exceed 0.03 mm/100 mm. 5.2.5 After keyway wear, it can be increased appropriately depending on the degree of wear; however, the maximum increase is one size level above the standard dimension. When the structure and load conditions permit, additional keyways can be created at 90° or 120° to the original keyway. 5.2.6 After wear of the shaft journal, it can be repaired by electroplating, spraying, or coating. 5.2.7 The bushing material shall comply with the drawings ； The shaft sleeve must be free of cracks, and its outer circular surface must not have any casting defects such as sand holes, pores, or porosity. 5.2.8 The fit between the bushing and the shaft is H8/h8 or H9/h9. 5.3 Rotor 5.3.1 The surface of the rotor and the inner walls of the fluid flow channels must be kept clean; there should be no sand adhesion, burrs, or dirt ； The junction between the machined surface and the unmachined surface at the inlet of the flow channel should have a smooth transition. 5.3.2 The impeller and shaft generally use an H7/h6 fit. 5.3.3 The newly installed impeller must be statically balanced, and the unbalanced weight resulting from this balancing process shall not exceed the values specified in Table 6 ； When exceeded, deburring should be performed by cutting from both sides of the impeller; the thickness removed shall not exceed 1/3 of the original wall thickness of the impeller, and the cut area shall meet smoothly with the uncut area. 5.4 Disassembly and assembly of the rotor section 5.4.1 When removing components such as shaft sleeves, impeller nuts, and rolling bearings, if they are stuck due to rust, soak them in kerosene or a rust remover before attempting to remove them; do not strike them forcefully. 5.4.2 After assembly, the radial runout of the outer surface of the seal area on the impeller and the outer surface of the shaft sleeve shall not exceed the values specified in Table 7. Table 6: Outer diameter of the rotor, in mm – ≤ 200, 201–300, 301–400, 401–500, 501–700, 701–900. Allowable unbalance weight, in g: 3, 5, 6, 10, 15, 20. 5.4.3 The diameter clearance between the outer surface of the rotor’s sealing area and the sealing ring is specified in the drawings; if no such data are available, values can be selected from Tables 8 to 10. Among them: Table 8 applies to pumps made of cast iron and bronze ； Table 9 applies to pumps made of carbon steel and Crl3 steel ； Table 10 applies to pumps made of 1Cr18N19 or similar acid-resistant steels. The gaps around should be even. 5.5 Rolling Bearings 5.5.1 The rollers and raceways of rolling bearings should be free from defects such as pits and rust spots; the retainers must be in good condition, the contact surface should be smooth, and there should be no abnormal noises during rotation. 5.5.2 The dimensions of the shaft journal that mates with the rolling bearing and the bearing housing shall comply with the specifications in the drawings. 5.5.3 The gap between the shaft pressure cover and the end face of the rolling bearing shall not be greater than 0.10 mm ； The clearance between the bearing cover on the expanded side of the shaft and the end face of the rolling bearing should be determined based on the length of the shaft between the two bearings and the temperature of the medium, ensuring an adequate amount of clearance is provided. 5.5.4 Special mounting and removal tools or a press should be used for mounting and removing rolling bearings, and the method must be correct. Do not strike the bearing directly with a hammer. After assembly, the end face of the bearing inner ring should be in close contact with the shaft shoulder. 5.5.5 When installing bearings on shaft journals by heating, they should be heated in engine oil at a temperature not exceeding 120°C or using a bearing heater; direct flame heating is strictly prohibited. 5.6 Sliding bearings 5.6.1 The bond between the bearing alloy and the bearing shell should be tight and secure, with no pores or defects on the surface. 5.6: The contact angle between 2 and the journal is in the range of 60°–90° at the middle part of the lower bearing shell (the lower limit applies when the rotation speed is >1000 r/min, while the upper limit applies when the rotation speed is <1000 r/min). The contact is even; when checked using the coloring method, there should be 2–4 color spots per square centimeter. 5.6.3 The top clearance of the bearing shells shall be selected according to Table 11. 5.7 Sealing Devices 5.7.1 Packing Seals 5.7.1.1 The surface roughness of the shaft sleeve (or shaft) at the packing box shall not exceed a certain value. 5.7.1.2 The diameter clearance between the packing sleeve and gland, as well as the shaft sleeve (or shaft), shall be selected according to the table provided; the clearances around the perimeter should be uniform. 5.7.1.3 The fit between the packing gland and the inner wall of the packing box is H11/d11. 5.7.1.4 The diameter clearance between the packing ring and the inner wall of the packing box is 0.15–0.20 mm; the diameter clearance between the packing ring and the shaft sleeve (or shaft) should be increased by 0.3–0.5 mm compared to the values given in Table 12. 5.7.1.5 The depth to which the gland is pressed into the packing box should be 0.5–1 turn of the packing height, with a minimum of 5 mm; the gland must not be skewed, and its tightness must be adjusted appropriately. 5.7.1.6 The packing joints should be butted at an angle, and the appropriate type of packing should be selected. 5.7.1.7 Ensure that the groove of the packing ring is aligned with the water seal hole on the packing box or slightly to the outside, so as to allow smooth water flow. 5.7.2 Mechanical Seals 5.7.2.1 Requirements for the shaft (or shaft sleeve) at the location where the mechanical seal is installed: a. The radial runout shall meet the specifications given in Table 7 ； b. Surface roughness ； c. The outer diameter deviation shall not exceed h6. 5.7.2.2 The axial play of the pump shaft shall not exceed ±0.5mm. 5.7.2.3 The flatness of the sealing surface where the moving ring meets the stationary ring must meet the required standards, and the surface roughness should be as specified for metal material sealing rings, and as specified for non-metal material sealing rings. The surface roughness at the contact points between the rotating ring, the stationary ring, and the auxiliary sealing ring should be. 5.7.2.4 Disassembly and assembly of mechanical seals a. Disassembly and assembly must be carried out carefully to avoid knocking or scratching the sealing surfaces of the moving and stationary rings as well as the auxiliary sealing rings; it is absolutely not allowed to use hammers or iron tools for striking ； b. During installation, the assembly area and mechanical seal must be cleaned thoroughly to prevent any impurities from entering the sealing area. The sealed cover can be coated with turbine oil or spindle oil during assembly ； ’ c. The compression amount of the spring must be appropriate, so that its length after compression is its operating length. 5.8 Couplings: The alignment deviation and end-face clearance of the two shafts in an elastic sleeve pin coupling shall comply with the standards specified in Table 13 below. 6. Commissioning and Acceptance 6.1 Preparations before commissioning 6.1.1 Remove all debris from the pump base and its surrounding area, and clean the site properly. 6.1.2 Check the tightness of the bolts for the pump base, motor base, and all connection bolts. 6.1.3 Check whether the seal meets the requirements and whether the cooling system is unobstructed. 6.1.4 Apply lubricant (grease) as specified. 6.1.5 For the idling motor, check the rotation direction; once it is correct, install the coupling pin. 6.2 Commissioning 6.2.1 Rotate the pump for two weeks, paying attention to any abnormal noises inside the pump and whether the rotation is smooth; reinstall the protective cover after rotation. 6.2.2 Introduce or fill the pump with liquid and remove air. 6.2.3 Start the pump in accordance with the starting procedure; once it operates normally after startup, continuous operation for testing can proceed. 6.2.4 The testing time shall be no less than 2 hours, and the following shall be achieved: a. Smooth operation without abnormal noises, with proper cooling and lubrication ； b. Bearing temperature is normal ； c. The vibration of the housing at the bearing area shall not exceed the specified limits ； d. The flow rate and head reach the values specified on the nameplate or the rated capacity ； The motor current does not exceed the rated value ； e. The sealing meets the requirements. 6.3 Acceptance: If the quality of the pump after maintenance meets the requirements of these regulations, if the maintenance records are complete and accurate, and if the trial operation proceeds smoothly, then acceptance can be carried out in accordance with the relevant procedures. 7 Safety Precautions for Maintenance and Repair 7.1 Safety Precautions for Maintenance 7.1.1 No maintenance tools or any objects shall be placed on the pump base. 7.1.2 Do not wipe the equipment near the rotating parts while the pump is in operation. 7.1.3 Keep the motor grounding wire in good condition, and be careful not to spray water on the motor during cleaning. 7.2 Safety Precautions for Maintenance 7.2.1 Maintenance personnel shall comply with the safety operating procedures specific to their job, as well as the company’s relevant regulations regarding safe maintenance work. 7.2.2 Relevant safety maintenance procedures must be carried out before maintenance. 7.2.3 Turn off the power supply and hang a “Do Not Operate” sign. 7.2.4 Drain the remaining liquid, close the inlet and outlet valves, or install blind flanges to isolate the system. 7.2.5 The removed, cleaned, and replaced parts, as well as the maintenance tools, should be neatly arranged to ensure orderly maintenance work. 7.3 Safety Precautions for Testing 7.3.1 Testing should be carried out in an organized manner, with a dedicated person responsible for ensuring safety during the testing process. 7.3.2 Pump start-up and shutdown shall be carried out by designated personnel, who must hold the \"Safety Operation Certificate\" for that position. 7.3.3 Start and stop the pump strictly in accordance with the operating procedures for starting and stopping the pump. 7.3.4 If abnormal noises or other irregularities are detected during testing, the machine should be stopped to investigate the cause; it must be resolved before attempting to continue testing. Is it this one? If it’s incorrect, please write in more detail. This post was last edited by lxzzl on 2009-2-19 16:04.]