Abstract: Borehole conditions can be determined using distributed measurement data. Real time data measurements can be taken from sensors distributed along the length of a drill string to assess various conditions or properties of the borehole. In particular, the distributed data can be used for example, to track the progress of a chemical pill or also track the location of different types of borehole fluids, and also to determine the hole size or volume of the borehole.

Abstract: Methods and apparatus are described that combine a measurement of the physical velocity of material within the annulus of a well between the drill pipe and the wall of the well with a measurement of the area of the flow as determined from a measurement of distance between the drill pipe and the wall of the hole to determine the actual material volumetric flow rate. Changes in volumetric flow rate at one or more points along the well can be used to determine the occurrence and location of well dysfunctions. This knowledge can then be used to make decisions about treating well dysfunctions which will lead to more efficient use of drilling rig time.

Abstract: Methods and apparatus are described that combine a measurement of the physical velocity of material within the annulus of a well between the drill pipe and the wall of the well with a measurement of the area of the flow as determined from a measurement of distance between the drill pipe and the wall of the hole to determine the actual material volumetric flow rate. Changes in volumetric flow rate at one or more points along the well can be used to determine the occurrence and location of well dysfunctions. This knowledge can then be used to make decisions about treating well dysfunctions which will lead to more efficient use of drilling rig time.

Abstract: Methods of determining borehole conditions using distributed measurement data are disclosed herein. The disclosed methods utilize real time data measurements taken from sensors distributed along the length of a drill string to assess various conditions or properties of the borehole. The disclosed methods of processing or using distributed measurement data have not been described before. In particular, the distributed data may be used for example, to track the progress of a chemical pill or also track the location of different types of borehole fluids, and also to determine the hole size or volume of the borehole.

Abstract: Methods and systems are described for drilling a well while distinguishing circulated gas or air from pumps-off gas in a drilling fluid at downhole pressure and temperature. A well is drilled with a drilling fluid, drill string, and drill bit. Drilling fluid is pumped through the drill string, drill bit, and into an annulus between the drill string and a wellbore. The drill string comprises one or more sensors sensing a parameter indicative of circulated gas or air in the drilling fluid flowing through the drill string, one or more sensors being behind and near the drill bit. The sensors measuring gas in the drill string may be at the same level as gas detectors in the annulus. The measurements are communicated to a human-readable interface at the surface, allowing an operator to determine if pressure of the wellbore fluid is greater than formation fluid pressure.