Standard operating procedures for water pumps

I. Legend: Indicates the operation； ( ) indicates confirmation ； Indicates safety ； { } indicates the signature ； */*It indicates collaborative operation. II. Position: refers to command ； Tech: refers to technical personnel ； Class leader: Refers to the person in charge of the class ； Inner: Indicates internal operations ； External: Indicates external operations. III. Filling instructions: 1. After completing the execution steps, mark a checkmark in the ( ) or commas“√” ； 2. After confirming the steps, enter the name of the person who confirmed and the time in {Confirmer: }. I. Preparation and verification work: Initial state S0 – Air in the centrifugal pump: isolated; mechanical and electrical systems are ready. Outside ( ) – Verify that the pump has completed its individual testing. (Including motor direction, vibration, current, temperature, sound) ( ) – Confirm that the pump is free of process medium. ( ) – Confirm that the coupling has been installed. (The hot oil pump coupling must be disengaged) ( ) – Verify that the protective cover is properly installed. ( ) – Mechanical, instrumentation, and electrical aspects of the pump have been verified. ( ) – Verify that the pump is turned evenly and smoothly. ( ) – Verify that the pump’s inlet filter is clean and properly installed. ( ) – Confirm that the water supply to the mechanical seal cooling water main is normal. ( ) – Confirm that the water supply from the main cooling water pipe to the pump is normal. ( ) – Confirm that the pump seal oil has been led to in front of the main valve. ( ) – Confirm that the grade of pump lubricating oil complies with the specifications. ( ) – Verify that the lubricant level in the bearing housings before and after the pump is between 1/2 and 2/3 of the sight glass. ( ) – Verify that the pump’s outlet and inlet valves are closed. ( ) – Confirm that the drain valve at the pump outlet is closed. ( ) – Confirm that the pump’s drain valve is closed. ( ) – Confirm that the pump’s heat pump line valve is closed. ( ) – Confirm that the steam purge line valves before and after the pump inlet manual valve are closed, and the drain valve is open. {Verifier} 1. Preparation confirmation for pump startup (1) Activate the pressure gauge – Activate the pressure gauge at the pump outlet as prescribed. – Install the pressure gauge on the sealed flushing oil line as specified. {Approver} (2) Cooling system of the operating pump – Open the main return valve and all branch valves of the pump’s circulating cooling water system. ] – Open the main feed valve and the individual branch valves of the pump-driven circulating cooling water system. ] – Close the pump circulating cooling water cross-line valve (reduce flow in winter but do not close it completely). ( ) – Verify that the pump-driven cooling water system is unobstructed. ] – Use steam for cooling the end face of the pump; control the steam used for end-face cooling based on the amount of water dripping from the end face. {Approver} (3) The lubricating oil system of the pump in service is in initial state S0: the pump is in standby mode and there is insufficient lubricating oil. First, confirm that the lubricant used is of the grade required by the pump. ( ) Fill the lubricant in accordance with the three-stage filtration standards for lubricants. [ ] Unscrew the oil filler cap. [ ] Place the oil funnel (which must be equipped with a filter of the mesh size specified in Step 3) over the threaded opening. [ ] Align the spout of the oil can with the funnel and slowly pour in the lubricating oil. ( ) Verify that the oil level at the filling point is at 1/2 or 2/3 of the total capacity. (The actual normal oil level range shall be determined according to the markings on site.) [ ] – Crank the machine to ensure proper lubrication of the pump bearings. (Cranking angle: n×360° + 180° in the direction of pump operation, where n > 1 and n ∈ N+) Warning card: It is not recommended to perform this procedure while the pump is in operation. It is indeed necessary to recommend filling it up after switching to the backup pump! Final status: The lubricating oil level in the SF pump is within the normal range. Status confirmation: The standby pump is in good condition and ready for use. Initial state S1: The centrifugal pump meets the conditions for warm-up. 2. Warm-up of the pump (this step applies to hot oil pumps). (1) Pressure testing of the pump body – Seal oil is used for this purpose. (Inspection items: The valve leading to the relevant pressure gauge is closed, and the seal oil pressure gauge is opened.) Dynamic seal leakage, leakage at all relevant flange surfaces). Precautions: The voltage increase must be gradual, in accordance with the equipment requirements ； Do not cause fluctuations in the pressure of the main oil sealing pipe ； When checking the dynamic seal, the shaft must be turned to the proper position. ) Outside] – Steam pressure testing is used. (Inspection items: Whether the valves leading to the relevant pressure gauges are closed, leakage at the dynamic seals, and leakage at all relevant flange surfaces.) Precautions: The temperature and pressure should be increased gradually, in accordance with the equipment requirements ； When checking the dynamic seal, the shaft must be turned to the proper position ； After the pressure testing is complete, the steam and condensate water inside the pump are drained. ) Note: For the two methods mentioned above, the appropriate method must be determined based on the actual operating conditions of the device. (2) Feed pump exterior] – Use a hot oil pump with seal oil pressure testing, and reduce the amount of seal oil injected. External] – Slowly open the pump inlet valve, then readjust the seal oil injection rate so that the seal oil pressure is approximately 0.5 MPa higher than the inlet pressure, until the pump inlet valve is fully open. Precautions: Ensure a steady flow rate when operating the pump. Note: Media that pollute the environment should be contained in containers, and high-temperature media should be used to prevent burns. (3) Warm-up pump [External] – Slowly and slightly open the pump outlet preheating valve. External] – Slowly adjust the valve on the warm pump line to control the heating rate of the warm pump to no more than 50°C/hour. Outside ( ) – Ensure the pump does not rotate in reverse. Outside ( ) – Verify that the operating pump does not exceed current limits. Outside ( ) – Ensure stable control of the flow rate and pressure of the process medium in the pump. Outside ( ) – Verify that the operating pump is not in a state of vacuum or partial vacuum. External] – Rotate the pump shaft every half hour until it reaches the temperature of the medium. (Crank angle: According to the pump’s operating direction, n=360°+180°, where n>1 and n∈N+) Outside ( ) – Verify that there is no leakage at the end face. Outside ( ) – In the initial stage of preheating, check whether there are any leaks at the static seal surfaces of the pump body and its associated pipelines. Outside ( ) – Ensure that the temperature difference between the pump body and the medium is less than 50°C. (3) Outside the thermal calibration center – Contact the pump repair thermal calibration center. Outside ( ) – Verify that the coupling is properly connected, then close the cover. External ( ) – Confirm that the pump can be cranked smoothly without any sticking. Initial state S2: The centrifugal pump is ready for operation. 3. Start the pump: (1) Start the motor – Notify the electrical department to prepare for starting the motor. Outside] – Contact the electrician to supply power to the pump according to the power supply procedure. External ( ) – Confirm that power is supplied to the motor and it meets the conditions for startup. Outside ( ) – Confirm that the pump outlet valve is closed. Outer] – Close the warm pump line valve. Outside ( ) – Confirm that the pump inlet manual valve is fully open. Outside ( ) – Confirm that the valve leading to the pressure gauge related to the pump is open. Outside ( ) – Verify that the cranking is even and smooth. (Crank angle: According to the operating direction of the pump, n ranges from 0 to 360°, with n > 1 and n ∈ N+). Outside ( ): Ensure that the lubricant level in the bearing housing is between 1/2 and 2/3 of the gauge, and that the color of the lubricant is normal with no signs of emulsification. External/Internal] – Contact the operator at the control room; subsequently change the control valve to remote operation (M) and lock the valve position. (If it is a variable-frequency pump, it is necessary to ensure that the variable-frequency current remains at an appropriate level.) ) Prepare to start the motor. Outside] – Press the “Start” button and hold it for more than 3 seconds to start the motor. Outside ( ) – Confirm motor startup. Outside ( ) – Verify that the outlet pressure of the starter pump is not lower than the outlet pressure of the operating pump. Outside ( ) – Verify that the current of the starter pump motor remains constant and at a low level. Outside] – Stop the pump immediately if any of the following occur: {Verifier: } ( ) – Abnormal leakage ； ( ) – Abnormal vibration ； ( ) – Sparks or smoking ； ( ) – Abnormal noise ； ( ) – The current remains high. (2) Pump switching: Outside [ ] – slowly open the outlet valve of the standby pump [ ] – simultaneously and slowly close the outlet valve of the pump that is currently in operation. ［ ］– Until the outlet valve of the original operating pump is fully closed, and the outlet valve of the pump that is now in use is adjusted to an appropriate position to ensure a stable flow rate at the pump’s outlet. ［ ］－ Press the “Stop” button of the original operating pump and hold it for more than 3 seconds to shut down the motor. ( ) – Verify that the outlet pressure of the pump is normal, the outlet flow rate is normal, the end-face leakage is within normal limits, the motor current is normal, the vibration of the pump is normal, the cooling and seal oil systems of the pump are functioning properly, the temperatures of the motor and the pump’s end faces are normal, the lubrication system is working correctly, there is no leakage at the static sealing surfaces of the pump body and pipelines, and no abnormal noises are present. External/Internal] – Notify that the internal operation has been completed; the internal operator shall set the subsequent control valve at the pump outlet to automatic mode (A) based on the actual conditions. During the switching process, close coordination is necessary in order to minimize fluctuations in flow rate and pressure at the outlet. In the stable state S2, the centrifugal pump has been switched over. (3) Shut down the pump that is no longer in use and set it aside; slightly open the valve on the heating line of that pump. Outside ( ) – Confirm that the stopped pump is not rotating in reverse. Outside ( ) – Verify that the operating pump does not exceed current limits. Outside ( ) – Confirm that there are no fluctuations in the flow rate of the operating pump. Outside] – Rotate the shaft to confirm it moves smoothly without sticking, and there is no leakage at the end face. (Crank angle: Rotate 360° in the direction of pump operation, where n＞1 and n∈N+; rotate to the single or double line specified by the equipment.) ) Note: The preheating temperature of the shut-down pumps is normal. State S2: Centrifugal pump in thermal standby. 4. Shut down the pump for maintenance: (1) Power off the motor – Contact an electrician to shut down the pump. Outside ( ) – Confirm that the motor is powered off. {Approver} (2) Isolation of the pump – Close the pump outlet manual valve. Outside] – Close the pump heating pump line valve. Outside] – Close the pump inlet manual valve. Outside] – Close the oil supply valves for the pre-pump and post-pump seals. Outside] – Close the feed valve and return valve of the pump-driven circulating cooling water system. Outside] – Slightly open the cross-line valve for circulating water (for anti-freezing in winter). Outside] – If it is confirmed that the inlet and outlet valves do not close properly, contact maintenance to install blind flanges for isolation. (3) Pump evacuation: Outside ( ) – Verify that the pump flushing oil supply line, the steam purging line, and the blind flanges on the light (heavy) oil lines have all been removed. Outside ( ) – Confirm that the blind flange connecting the pump body to the sealed dirty oil line has been removed. Outside ( ) – Confirm that the device’s flushing oil system is in operation and has been connected to the area in front of the pump. Outside ( ) – Verify that the discharge process for heavy fuel oil from the pump outlet is unobstructed. Outside ( ) – Verify that the flow from the pump outlet to the sludge oil tank via the light sludge oil line is unobstructed. Outside ( ) – Verify that the hydrocarbon recovery pipeline and flare discharge pipeline at the pump outlet are unobstructed. Outside ( ) – Connect to the tank farm for the transfer of waste oil from the facility. Outside ( ) – Contact the dispatcher to have the pump unit discharge to the flare. Outside ( ) – Confirm that the pump temperature is below 100°C. Outside] – Open the valves from the pump outlet to the flushing oil line (2). Outside] – Slowly open the pump inlet flushing oil line supply valve and replace it for 20 minutes. Outside ( ) – Confirm that the oil inside the pump has been completely replaced by the flushing oil. Outside] – Close the pump inlet flushing oil supply valve. Outside] – Close the pump outlet flushing oil return valve. Outside] – Contact the tank farm to use steam for line cleaning of the oil waste transfer line outside the facility. Outside] – After draining all water at the steam purge point at the end of the sludge line, purge the sludge line for 20 minutes. Outside] – Close the steam purging valve after receiving a message from the tank area. Outside] – Open the valve from the pump bottom to the sealed sludge line. Outside] – Open the pump outlet vent valve to drain all the fluid from within the pump. Outside] – Slightly open the drain valve on the pump inlet steam purge line. Outside] – Open the manual valve before the drain valve of the pump inlet steam purge line; close the drain valve once steam is seen. Outside] – Open the manual valve of the steam purge line drain valve at the pump inlet, and purge the pump body for 3 minutes. Outside] – Close the pump inlet steam purge line valves (2); be careful to prevent freezing in winter. Outside] – Confirm that the liquid inside the pump has been completely drained. Outside] – Close the dirty oil line valve of the pump body. Outside] – Open the pump outlet vent valve. Note: When draining or discharging substances that pollute the environment, use containers to hold them. Substances at temperatures above 45°C can cause burns; corrosive substances can lead to scalds; toxic substances may cause poisoning; and liquefied gas can result in frostbite. (4) Blind flange isolation – Contact the maintenance team to install blind flanges at the following locations: ( ) – Flange between the two valves on the steam inlet line of the pump; ( ) – Install blind flanges at the locations indicated by the maintenance team. {Approver: } 5. Final confirmation when the pump is shut down – ( ) – The pump has been completely isolated from the system. ( ) – The pump has been drained, and the vent drain valve is open. ( ) – Motor power off. ( ) – Confirm that the ordinary low-pressure pump P- is in a condition suitable for maintenance. Final state FS: Centrifugal pump is under maintenance. V. Handling of common pump faults. Fault symptoms, Causes of faults, Solutions: 1. Decreased flow rate and head: (1) Gas present inside the pump or in the suction pipe. Refill the pump to remove the gas. (2) The impeller or pipes are blocked by debris; inspect and clean them. (3) The rotation speed is lower than the rated value; identify the cause of the low speed and eliminate it. (4) The impeller and mouth ring are worn out; disassemble and repair them. 2 Elevated current: (1) Collision between the rotor and stator; disassemble and repair it. (2) Friction in the rotating components. Inspection and repair: (3) Changes in the specific gravity and flow rate of the medium being transported; identify the cause and eliminate it. (4) Faulty ammeter – repair the ammeter. Increased vibration levels of Pump 3: (1) Loose bolts securing the coupling – tighten the bolts. (2) The pump is under vacuum; adjustments are required. (3) Poor shaft alignment; realign the shaft. (4) There are foreign objects inside the impeller, disrupting dynamic balance; remove these objects by disassembling the pump. (5) Severe bearing wear; repair or replace the bearings. (6) Insufficient bearing lubrication; use the correct lubricant and ensure proper oil level. (7) Excessive stress in the inlet and outlet pipelines; reconfigure the piping. (8) Loose foundation bolts; tighten them properly. 4 Severe sealing leakage: (1) The mechanical seal is damaged or installed incorrectly; inspect and replace it. (2) Insufficient pressure of the sealing fluid; address this issue and ensure that the sealing fluid pressure is 0.05 MPa to 0.15 MPa higher than the pressure in the sealing chamber. (3) The packing is too loose; adjust it accordingly. (4) Large fluctuations in operation; stabilize the process operations. (5) The moving ring of the pump’s seal is stuck. Have a blacksmith take care of it. 5. High bearing temperature: (1) Improper lubrication – Use the correct lubricant and maintain the proper oil level. (2) Insufficient or dirty oil in the bearing housing – Add oil or replace it. (3) Poor cooling of the bearings – Check and adjust the cooling water. (4) Worn bearings – Inspect and replace the bearings. (5) Worn bearing housing – Replace the bearing housing. 6. Pump shaft misalignment: (1) Vacuum or partial vacuum – Adjust the pump flow rate to prevent vacuum conditions. (2) Excessive clearance in the thrust bearings or poor fixation – Adjust the bearing clearance or improve its fixation. (3) Clogged balance tube – Check and clean it. (4) Worn balance disk – Replace the balance disk. 7. Oil leakage from the bearing housing: (1) Loose oil seal ring – Tighten the screws securing the oil seal ring. (2) Damaged oil seal – Replace the oil seal. (3) Excessive oil volume – Keep the oil level at 1/2 to 2/3 of the capacity. (4) Cracked bearing housing – Replace the bearing housing. (5) Imperfect sealing at the oil drain port of the bearing housing – Check and repair it. (6) Failed gasket on the bearing housing cover – Replace the gasket. VI. Precautions: 1. It is strictly prohibited to start or adjust the flow rate of a centrifugal pump by closing the inlet valve ； 2. Operation with the outlet valve closed shall not exceed three minutes ； 3. If the centrifugal pump experiences vacuum or partial vacuum conditions, it should be adjusted or dealt with immediately ； 4. Operation at excessive temperature, pressure, or load is strictly prohibited ； 5. When preheating the pump body of a hot oil pump, if venting is used for evacuation, the opening degree of the vent valve must be strictly controlled to avoid burns or fires.

The standard operating procedures lack information on how to shut down the pump and carry out maintenance!