Processing

Please wait...

PATENTSCOPE will be unavailable a few hours for maintenance reason on Tuesday 26.10.2021 at 12:00 PM CEST
Settings

Settings

Goto Application

1. WO2009006528 - CENTERING STRUCTURE FOR TUBULAR MEMBER AND METHOD OF MAKING SAME

Note: Text based on automatic Optical Character Recognition processes. Please use the PDF version for legal matters

[ EN ]

CLAIMS
What is claimed is:
1. A centralizer for maintaining a tubular member in a substantially centralized position within a borehole, comprising:
a substantially seamless material of substantially cylindrical shape having a
circumferential wall, an upper end, and a lower end;
a plurality of apertures in the circumferential wall having an upper end and a lower
end, wherein the apertures define an upper collar element, a lower collar
element of the circumferential wall, and bow spring elements disposed
between the upper collar element and lower collar element; wherein,
each bow spring element has a medial portion of the bow spring element that is
expandable radially such that the circumference of the centralizer is larger
around the medial portions of the bow spring elements than the around the
upper collar element and the lower collar element.

2. The centralizer of claim 1, wherein the substantially seamless material is substantially
homogeneous.

3. The centralizer of claim 1 or 2, wherein the bow spring elements are elastically deformable to reduce the circumference of the centralizer around the medial portions of the bow spring elements.

4. The centralizer of one of claims 1 to 3, further comprising a plurality of set screw holes extending radially through at least one of the upper collar element and the lower collar element.

5. The centralizer of claim 4, wherein the set screw holes are threaded.

6. A method of fabricating a centralizer for maintaining a tubular member in a substantially centralized position within a borehole, comprising: forming a plurality of apertures in a substantially seamless material of substantially
cylindrical shape having a circumferential wall, an upper end, and a lower
end to create an intermediate blank; wherein
the plurality of apertures in the circumferential wall having an upper end and a lower
end define an upper collar element, a lower collar element of the
circumferential wall, and bow spring elements disposed between the upper
collar element and lower collar element;
expanding a medial portion of the bow spring elements to cause plastic deformation
of the bow spring elements; whereby,
the circumference of the centralizer is larger around the medial portions of the bow
spring elements than the around the upper collar element and the lower collar
element.

7. The method of claim 6, wherein the substantially seamless material is substantially
homogeneous.

8. The method of claim 6 or 7, wherein the expanding further comprises:
inserting an expansion element having a substantially cylindrical shape with an upper
face, a lower face, and a flexible circumferential wall into the interior of the
intermediate blank;
applying a compressive force to at least one of the upper face and the lower face
causing the expansion element to expand radially as it is compressed axially.

9. The method of claim 8, wherein the applying a compressive force further comprises:
placing an upper mandrel and a lower mandrel in contact with the upper face and
lower face of the expansive element, respectively; and
applying a compressive force to at least one of the upper face and the lower face
through the upper mandrel and the lower mandrel, causing the expansion
element to expand radially as it is compressed axially.

10. The method of claim 8 or 9, wherein the expansion element being inserted into the interior of the intermediate blank is made of an elastomer which expands radially as it is compressed axially.

11. The method of claim 10, wherein the expansion element comprises a plurality of holes extending through the expansion element in a longitudinal direction of the expansion
element.

12. The method of one of claims 6 to 11, further comprising:
forming a plurality of set screw holes extending radially through at least one of the
upper collar element and the lower collar element.

13. The method claim 12, further comprising:
threading the plurality of set screw holes.