New Flowmeters for Kick and Loss Detection During Drilling

Abstract

ABSTRACT Well kicks and fluid losses during drilling are potentially dangerous. Early detection would result in a significant increase in drilling operation safety. Reliable measurements would allow the use of lower mud weights, resulting in faster drilling, less formation damage, and lower drilling costs. This paper describes a newly developed flowmetering system built to detect any difference between flow-in and flow-out of the well greater than 25 Gpm (1.5 L/s) This is a significant improvement over existing wellsite measurements. The flowmeters operate in both water and oil based muds, over the commercial range of mud weight and viscosity. The flow-in sensor is installed at the discharge of the triplex pump. The flow-out sensor is installed in the return line, just like the familiar paddle, with minimal modification of the rig equipment. Unlike the electromagnetic meter this flow-out sensor does not increase the risk of blockage by cuttings, because the mud flow path is neither modified nor restricted. Extensive testing has been performed on these systems. Several lab results are discussed, and results of full scale calibration with a wide range of mud properties are presented. Finally, field tests have confirmed the ability of the system to respond quickly and accurately to gain or loss during actual drilling operations.