Multiple distributed pressure measurements
Methods, computer programs, and systems for detecting at least one downhole condition are disclosed. Pressures are measured at a plurality of locations along the drillstring. The drillstring includes a drillpipe. At least one of the pressures is measured along the drillpipe. At least one downhole condition is detected based, at least in part, on at least one measured pressure.
1. A method of collecting and analyzing one or more pressures, comprising:
measuring pressures at a plurality of locations on a drillstring, the drillstring comprising a drillpipe, and where at least one pressure is measured by a pressure sensor located on or within the drillpipe; and
detecting at least one downhole condition based, at least in part, on at least one measured pressure, wherein the at least one downhole condition includes a fluid influx.
2. The method of claim 1 , where measuring pressures at a plurality of locations along a drillstring comprises:
measuring at least two of the pressures substantially simultaneously.
3. The method of claim 1 , where measuring pressures at a plurality of locations along a drillstring comprises:
measuring at least two of the pressures in a controllable sequence.
4. The method of claim 1 , further comprising:
identifying at least one downhole condition.
5. The method of claim 1 , further comprising:
locating at least one downhole condition.
6. The method of claim 1 , further comprising:
characterizing at least one downhole condition.
7. The method of claim 1 , where the drillstring comprises one or more drill collars, and where measuring pressures at a plurality of locations on the drillstring comprises:
measuring one or more pressures at one or more of the drill collars.
8. The method of claim 1 , where the drillstring comprises an interior and an exterior, and where measuring pressures at a plurality of locations on the drillstring comprises:
measuring at least one pressure on at least one of:
the exterior of the drillstring; or
the interior of the drillstring.
9. The method of claim 1 , where measuring pressures at a plurality of locations on a drillstring comprises:
measuring pressures at three or more locations on the drillstring;
and where detecting at least one downhole condition comprises:
detecting at least one downhole condition based, at least in part, on three or more measured pressures.
10. The method of claim 1 , where measuring pressures at a plurality of locations on a drillstring comprises:
measuring a first pressure in a first borehole section; and
measuring a second pressure in a second borehole section, where:
the first borehole section and second borehole section are different types of borehole sections; and were each of the first borehole section type and the second borehole section type are selected from a group of borehole section types consisting of:
a vertical section;
a curve section;
a tangent section; and
a horizontal section.
11. The method of claim 1 , further comprising:
creating a measured-value set comprising one or more measured pressures and corresponding depths.
12. The method of claim 11 , where at least one of the measured pressures in the measured-value set is measured along a flowline and corresponds to a depth at or near the top of the drillstring.
13. The method of claim 11 , where the measured-value set comprises at least three measured pressures and corresponding depths.
14. The method of claim 11 , further comprising:
providing at least two expected pressures along the drillstring corresponding to at least two depths; and
creating an expected-value set of expected pressures versus depth.
15. The method of claim 14 , further comprising:
displaying at least one graphical representation selected from the group comprising:
a graphical representation of the measured-value set;
a graphical representation of the expected-value set; and
a graphical juxtaposition of the measured-value set and the expected-value set.
16. The method of claim 14 , further comprising:
determining at least one pressure difference between an expected pressure at a depth and a measured pressured at about the depth.
17. The method of claim 16 , further comprising:
detecting at least one downhole condition based, at least in part, on one or more pressure differences.
18. The method of claim 14 , further comprising:
determining at least one measured-pressure gradient;
determining at least one expected-pressure gradient; and
determining at least one gradient difference.
19. The method of claim 18 , where determining at least one gradient difference comprises:
determining at least one gradient difference between a corresponding pair of one measured-pressure gradient and one expected-pressure gradient, where each of the measured-pressure gradient and the expected-pressure gradient in the corresponding pair correspond to at least partially overlapping depths.
20. The method of claim 19 , further comprising:
identifying at least one downhole conditions based, at least in part, on one or more gradient differences.
21. The method of claim 1 , wherein the at least one pressure measured by a pressure sensor located on or within the drillpipe is measured by a pressure sensor located on or within an interface between two joints of drillpipe.
22. The method of claim 1 , wherein the at least one pressure measured by a pressure sensor located on or within the drillpipe is measured by a pressure sensor located on or within a sub between two joints of drillpipe.
23. The method of claim 1 , wherein the at least one pressure measured by a pressure sensor located on or within the drillpipe is measured by a pressure sensor located on or within a drillpipe joint.
24. The method of claim 1 , wherein the at least one pressure measured by a pressure sensor located on or within the drillpipe is measured by a pressure sensor located on or within a gasket between two joints of drillpipe.