Method and system for measurement of fluid flow in a drilling rig return line

摘要: Improved methods and systems are provided for determining a volumetric flow rate of mud in return line without the aid velocity probe. A level sensor is located chimney preferably close proximity to bell nipple. The senses height flowing line. Where an ultraonsic transceiver used as sensor, temperature sensors determine gradient which provides speed sound correction does target at known distance from transceiver. computer receives uncorrected information, determines flow-out volume mud. Flow-out related height, geometry line, parameters. In more complete system, calibrates determined with flow-in volume, factor provide corrected determination. also monitors delta (flow-out minus flow-in), based on change when undesirable condition such kick or fluid loss occurs. system be rig subject movement (e.g. floating rig), angle employed help instantaneous flow-out, determinations averaged over cycle by heave position available rig.