Abstract: Embodiments of this disclosure confirm a leak and determine a depth of the leak in a well of a drilling system. The drilling system include a circulating fluid and a fluid caliper having a density contrast relative to a density of the circulating fluid. Fluid mass flow and fluid density data are continually collected by an inlet and outlet side flow measurements. A measured surface pressure, a measured downhole pressure, a user-defined managed depth window, and a target equivalent circulating density at the user-defined managed depth window are inputted to a microprocessor. The microprocessor adjusts the fluid density data for temperature and pressure; calculates a mass flow balance and a wellbore pressure; compares the measured density and mass flow in with the measured density and mass flow out; and determines, based upon the comparing, the presence of the leak and the depth of the leak.

Abstract: Embodiments of a system and method of this disclosure continually determine a mass balance of a drilling or circulating system, using mass flow and density data adjusted for temperature and pressure. The system and method may be used to continually monitor and control wellbore pressures to achieve over-balanced managed pressure drilling (“MPD”). In some embodiments, the system and method may be used as a fluid tracking engine. In other embodiments, the system and method may be used to accurately track a fluid caliper intended to survey the well to determine string volumes or borehole volumes; an example is determining the volume of cement needed to circulate the cement or bring the cement up to desired height. The system and method may be used to track the effects of mixing. The system and method may also be used as a viscometer.