Self tracking sensor suspension mechanism

• US 6,640,655 B1
• Filed: 10/03/2000
• Issued: 11/04/2003
• Est. Priority Date: 10/03/2000
• Status: Expired due to Term

• Current Assignee: NDT Systems & Services AG (Institut Dr. Foerster GmbH & Co. KG)
• Original Assignee: Varco I/P Incorporated (NOV, Inc.)
• Inventors: Manzak, Paul T., Torres, Carl R. Jr.
• Primary Examiner(s): RAEVIS, ROBERT R
• Application Number:
  US09/677,883
• Time in Patent Office: 1,127 Days
• Field of Search: 73/86, 738/658, 736/23, 736/34, 335/44, 335/441-544, 337/77, 324/220, 324/221, 324/173, 324/174, 324/168, 324/777
• US Class Current: 73/865.8
• CPC Class Codes: F17D 5/00 Protection or supervision of installations arrangements for protecting foundations E02D31/00; protecting pipes from damage or internal or external wear F16L57/00, against corrosion and scale F16L58/00; investigation of the fluid-tightness of structures G01M3/00

Abstract

The invention relates to a self-tracking sensor mechanism for use with a smart pipeline inspection gauge, commonly termed a “smart pig”. The self-tracking sensor mechanism has a link pivotally attached to a body portion of the pig and a spring for urging the link in a direction away from the body portion of the pig and toward the wall of the pipeline being inspected. A trailing arm is pivotally connected to the link. The trailing arm has a sensor that is maintained in contact with the pipeline interior surface to be inspected during travel of the pig through the pipeline.

Claims

1. A pig for traveling within a pipeline, said pig including a body portion to which a plurality of self-tracking sensor mechanisms are attached;

each of said self-tracking sensor mechanisms comprising a link pivotally attached to said body portion of said pig at one end thereof, first means for urging said link in a direction away from said body portion, a trailing arm pivotally connected at one end thereof to said link, second means independent of said first means for urging said trailing arm in a direction away from said body portion, and a sensor connected to a surface portion of said trailing arm for contact with a pipeline interior surface when said pig is traveling within said pipeline.

2. The pig of claim 1, wherein said first means for urging said link in a direction away from said body portion is a first spring.

3. The pig of claim 2, wherein said second means for urging said trailing arm in a direction away from said body portion is a second spring.

4. The pig of claim 3, wherein said link is pivotally attached to said body portion by a pin extending through said link at said one end thereof.

5. The pig of claim 4, wherein said trailing arm is pivotally connected to said link by a pin extending through said link and said trailing arm at said one end of said trailing arm and at said another end of said link.