Formation evaluation while drilling

• US 7,845,405 B2
• Filed: 01/19/2009
• Issued: 12/07/2010
• Est. Priority Date: 11/20/2007
• Status: Active Grant

• Current Assignee: Schlumberger Technology Corporation (SLB)
• Original Assignee: Schlumberger Technology Corporation (SLB)
• Inventors: Harms, Kent D., Villareal, Steven G., Pop, Julian J., Bolze, Victor M.
• Primary Examiner(s): Thompson; Kenneth
• Assistant Examiner(s): Andrish; Sean D
• Application Number:
  US12/355,956
• Publication Number:
  US 20090126996A1
• Time in Patent Office: 687 Days
• Field of Search: 175/59, 166/264, 166/100
• US Class Current: 166/264
• CPC Class Codes: E21B 17/16 Drill collars
• CPC Class Codes: E21B 49/081 with down-hole means for trapping a fluid sample E21B49/10 takes precedence

Abstract

A sample module for a sampling while drilling tool includes a sample fluid flowline operatively connectable between a sample chamber and an inlet, for passing a downhole fluid. A primary piston divides the sample chamber into a sample volume and a buffer volume and includes a first face in fluid communication with the sample volume and a second face in fluid communication with the buffer volume. An agitator is disposed in the sample volume for agitating the sample fluid. A secondary piston includes a first face in fluid communication with the buffer volume having buffer fluid disposed therein and a second face.

Claims

1. A sample module for a sampling while drilling tool positionable in a wellbore penetrating a subterranean formation, comprising:

a sample chamber having an inlet configured to receive a downhole fluid from a sample fluid flowline;

a primary piston slidably disposed within the sample chamber and dividing the sample chamber into a sample volume and a buffer volume; and

an agitator disposed in the sample volume and comprising an inner core and an outer body, wherein the outer body comprises a material having a lower hardness than an interior wall of the sample chamber.

2. The sample module of claim 1 wherein the inner core comprises a material having a greater hardness than the material of the outer body.

3. The sample module of claim 1 wherein the outer body substantially comprises PEEK (polyetheretherketone) and the inner core substantially comprises metal.