Apparatus and method for formation evaluation

• US 7,584,786 B2
• Filed: 04/24/2007
• Issued: 09/08/2009
• Est. Priority Date: 10/07/2004
• Status: Active Grant

• Current Assignee: Schlumberger Technology Corporation (Schlumberger NV)
• Original Assignee: Schlumberger Technology Corporation (Schlumberger NV)
• Inventors: Del Campo, Christopher S., Nold, Raymond V. III, Zazovsky, Alexander F., Briquet, Stephane, Ervin, Steve
• Primary Examiner(s): Bagnell; David J
• Assistant Examiner(s): ANDREWS, DAVID L
• Application Number:
  US11/739,536
• Publication Number:
  US 20070209793A1
• Time in Patent Office: 868 Days
• Field of Search: 166/264, 166/100, 166/250.17, 166/185, 731/522.4, 731/522.6
• US Class Current: 166/100
• CPC Class Codes: E21B 49/10 using side-wall fluid samplers or testers

Abstract

A method for acquiring a sample of a virgin fluid from a subsurface formation penetrated by a wellbore surrounded by a layer of contaminated fluid includes abutting a first packer against a wall of the wellbore, and extending at least a portion of a second packer beyond the first packer, wherein the second packer is at least partially disposed in the first packer. An inlet to a first flowline is at least partially defined by the first packer, and an inlet to a second flowline is defined by the second packer. The method further includes drawing one of virgin fluid, contaminated fluid and combinations thereof into the first flowline; and drawing virgin fluid into the second flowline.

Claims

1. A probe assembly for employment by a downhole tool disposed in a wellbore surrounded by a layer of contaminated fluid, the wellbore penetrating a subsurface formation having a virgin fluid therein beyond the layer of contaminated fluid, the probe assembly comprising:

a probe body extendable from the downhole tool;

an outer packer disposed in the probe body for sealingly engaging a first portion of the wellbore, the outer packer having a bore therethrough;

an inner packer disposed in the bore of the outer packer and forming an annulus therebetween, the inner packer being extendable beyond an outer surface of the outer packer for sealingly engaging a second portion of the wellbore within the first portion of the wellbore;

a first inlet in the probe body fluidly communicating with the annulus and for admitting one of virgin fluid, contaminated fluid and combinations thereof into the downhole tool;

a flow line fluidly coupled to the first inlet and including a filter for filtering particles from the fluid, the filter comprising a cleaning device associated therewith;

a second inlet in the probe body fluidly communicating with the inner packer for admitting virgin fluid into the downhole tool; and

a flow line fluidly coupled to the second inlet and including a filter for filtering particles from the fluid, the filter comprising a cleaning device associated therewith;

wherein a sampling tube is operatively connected to the inner packer; and

further comprising a piston disposed within the sampling tube, wherein the piston comprises an axial passageway therein and one or more perforations in a sidewall thereof for conducting virgin fluid admitted to the sampling tube to the axial passageway, the axial passageway fluidly communicating with the second inlet in the probe body.

2. The probe assembly of claim 1, wherein the probe body is extendable under hydraulic pressure delivered from the downhole tool.

3. The probe assembly of claim 1, wherein at least one of the outer packer and the inner packer is elastomeric.

4. The probe assembly of claim 1, wherein the sampling tube is moveable relative to the outer packer.

5. A probe assembly for employment by a downhole tool disposed in a wellbore surrounded by a layer of contaminated fluid, the wellbore penetrating a subsurface formation having a virgin fluid therein beyond the layer of contaminated fluid, the probe assembly comprising:

a probe body extendable from the downhole tool;

an outer packer disposed in the probe body for sealingly engaging a first portion of the wellbore, the outer packer having a bore therethrough;

an inner packer disposed in the bore of the outer packer and forming an annulus therebetween, the inner packer being extendable beyond an outer surface of the outer packer for sealingly engaging a second portion of the wellbore within the first portion;

a first inlet in the probe body fluidly communicating with the annulus for admitting one of virgin fluid, contaminated fluid and combinations thereof into the downhole tool;

a second inlet in the probe body fluidly communicating with the inner packer for admitting virgin fluid into the downhole tool; and

a piston disposed within a sampling tube that is operatively connected to the inner packer, wherein the piston comprises an axial passageway therein and one or more perforations in a sidewall thereof for conducting virgin fluid admitted to the sampling tube to the axial passageway, the axial passageway fluidly communicating with the second inlet in the probe body.

6. A downhole probe assembly for employment in a wellbore surrounded by a layer of contaminated fluid, the wellbore penetrating a subsurface formation having a virgin fluid therein beyond the layer of contaminated fluid, the probe assembly comprising:

an outer packer configured to sealingly engage a first portion of the wellbore;

an inner packer disposed in a bore of the outer packer forming an annulus therebetween and configured to extend beyond an outer surface of the outer packer to sealingly engage a second portion of the wellbore within the first portion;

a first inlet fluidly communicating with the annulus;

a second inlet fluidly communicating with the inner packer; and

a piston disposed within a sampling tube that is operatively connected to the inner packer, wherein the piston comprises an axial passageway and a sidewall perforation configured to conduct fluid admitted to the sampling tube to the axial passageway, and wherein the axial passageway fluidly communicates with the second inlet.