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Operating Procedures for Mass Flow Meters 1 Scope of Application These procedures apply to mass flow meters used for measuring crude oil at transfer pump stations. These procedures specify the inspection steps before putting a crude oil mass flow meter into operation, the operations for commissioning it, the inspection steps during operation, and the procedures for shutting it down. 2 Operation Procedures 2.1 Pre-commissioning inspections 2.1.1 Wear appropriate personal protective equipment, conduct hazard identification and risk analysis, and implement necessary risk mitigation measures. 2.1.2 Check that the flow meter configuration, sensors, and transmitters are functioning properly; verify that the flow meter is installed as required, with accurate and reliable wiring; ensure that the meter’s measurement range, temperature resistance, and pressure resistance match those of the fluid being measured. 2.1.3 Check that all seals on the flowmeter are in good condition and that all connections are tight. 2.1.4 Check that the instruments are in good condition and zero them out as specified. 2.1.5 Power on the transmitter and preheat it for ≥30 minutes to ensure that it is in a safe mode that permits flowmeter adjustment. 2.2 Commissioning 2.2.1 Turn on the power supply for the flow meter. 2.2.2 Slowly open the inlet valve of the flow meter to ensure a gradual increase in pressure within the flow meter system, and check that there are no leaks at the flanges, valves, and their connecting pipelines. 2.2.3 Slowly open the filter exhaust valve to release the internal gas. 2.2.4 Slowly open the outlet valve of the flow meter, check that the gauge reading is normal to confirm that the flow meter is operating properly, then slowly close the bypass valve or shut down the flow meter if it is to be stopped. 2.3 Inspections during operation 2.3.1 Check the instrument readings on time to ensure normal operating conditions, with instantaneous and cumulative values matching the actual values. 2.3.2 Conduct regular comprehensive inspections of the flow meters in operation, address any issues found promptly, and keep proper records. 2.4 Shutdown 2.4.1 When shutting down a flow meter, first activate the backup flow meter or enable the bypass system. Only after confirming that the backup flow meter is operating properly or that the bypass system is functioning correctly can the flow meter to be shut down be taken out of service. 2.4.2 Close the inlet and outlet valves of the flow meter, and record the flow meter reading and the downtime. 2.4.3 When a flow meter installed outdoors is out of service for an extended period, clean the remaining liquid inside it promptly. 3 Precautions 3.1 Perform comprehensive maintenance and zero adjustment every three months. Before performing the zero adjustment, the temperature reading of the sensor should be close to its normal operating temperature; the sensor must be filled with fluid, and no flow of medium should be present at the time of zero adjustment. 3.2 Check the connections of the flowmeter inserts annually. 3.4 When a new pipeline is put into operation upstream of the flow meter, measures must be taken to prevent blockages of the flow meter.