Low-debris low-interference well perforator

Patent metadata

Field	Value
Publication number	US-10151180-B2
Application number	US-201515736455-A
Country	US
Kind code	B2
Filing date	Jul 20, 2015
Priority date	Jul 20, 2015
Publication date	Dec 11, 2018
Grant date	Dec 11, 2018

Abstract

A low-debris low-interference semi-solid well perforator having selectively variable free volume and method for providing such is disclosed according to one or more embodiments. The perforator may include a charge tube holding an independently floating axial stack of selectively variable divider segments, each having one or more concavities formed in upper and lower sides. The segments are arranged so that concavities of adjacent segments form sockets, into which shaped charges are located. The segments provide support to minimize deformation of shaped charge cases yet provide less than 360 degrees circumferential contact about the shaped charges to form selectively variable voids for collecting debris and spall resulting from detonation. The voids and floating segments attenuate detonation shock interference. A debris guard prevents debris from entering the wellbore. Relieving slots in the debris guard attenuates transmission of shock interference through the debris guard.

First claim

What is claimed:

1. A well perforator, comprising:
a charge tube having a wall with a first opening formed therethrough centered at a first radial of said charge tube;
a circular first divider segment disposed within said charge tube, said first segment having a first concavity formed in a lower side of said first segment along said first radial of said charge tube;
a circular second divider segment disposed within said charge tube below said first segment, said second segment having a first concavity formed in an upper side of said second segment along said first radial of said charge tube;
said first concavities of said first and second segments together defining a first socket aligned with said first opening of said charge tube;
a first shaped charge disposed within said first socket; and
a first void formed between said first segment and said second segment.

2. The perforator of claim 1 wherein:
said first void is formed along a radial of said charge tube opposite said first radial;
said first void is a generally planar transverse void oriented perpendicular to an axis of said perforator; or
said first and second segments contact only a portion of an outer casing of said shaped charge thereby defining a shaped charge void formed between said socket and said first shaped charge.

3. The perforator of claim 1 wherein:
said first segment provides less than 180 degrees of circumferential contact with an outer casing of said shaped charge; and
said second segment provides less than 180 degrees of circumferential contact with said outer casing of said shaped charge; whereby
said lower side of said first segment does not contact said upper side of said second segment to form said first void.

4. The perforator of claim 1 further comprising:
a debris opening formed through said charge tube in fluid communication with said first void; or
a hollow carrier, said charge tube coaxially disposed within said hollow carrier.

5. The perforator of claim 4 further comprising:
a debris guard covering said debris opening.

6. The perforator of claim 5 further comprising:
a relieving slot formed through said debris guard at a position not adjacent to said debris opening.

7. The perforator of claim 5 wherein:
said debris guard is a cylindrical sleeve; and
said charge tube is coaxially disposed within said debris guard.

8. The perforator of claim 7 further comprising:
a gun port aperture formed through a wall of said debris guard centered at said first radial of said charge tube.

9. The perforator of claim 2 further comprising:
a second opening formed through said wall of said charge tube centered at a second radial, respectively, of said charge tube;
a second concavity formed in said lower side of said first segment along said second radial of said charge tube;
a second concavity formed in said upper side of said second segment along said second radial of said charge tube;
said second concavities of said first and second segments together defining a second socket aligned with said second opening of said charge tube;
a second shaped charge disposed within said second socket; and
a second void formed between said first segment and said second segment along a radial of said charge tube opposite said second radial.

10. The perforator of claim 9 wherein:
said second radial of said charge tube is 180 degrees from said first radial of said charge tube.

11. The perforator of claim 9 further comprising:
a third opening formed through said wall of said charge tube centered at a third radial of said charge tube;
a third concavity formed in said lower side of said first segment along said third radial of said charge tube;
a third concavity formed in said upper side of said second segment along said third radial of said charge tube;
said third concavities of said first and second segments together forming a third socket aligned with said third opening of said charge tube;
a third shaped charge disposed within said second socket; and
a third void formed between said first segment and said second segment along a radial of said charge tube opposite said third radial.

12. The perforator of claim 11 wherein:
said second radial of said charge tube is 120 degrees from said first radial of said charge tube; and
said third radial of said charge tube is 240 degrees from said first radial of said charge tube and 120 degrees from said second radial of said charge tube.

13. The perforator of claim 11 wherein:
said first void is operable to receive spall resulting from detonations of said second and third shaped charges;
said second void is operable to receive spall resulting from a detonation of said first shaped charge and said detonation of said third shaped charge; and
said third void is operable to receive spall resulting from said detonations of said first and second shaped charges.

14. The perforator of claim 11 further comprising:
fourth, fifth, and sixth concavities formed in an upper face of said first segment offset from said first radial of said charge tube by 60, 180, and 300 degrees, respectively;
fourth, fifth, and sixth concavities formed in a lower face of said second segment offset from said first radial of said charge tube by 60, 180, and 300 degrees, respectively;
a fourth shaped charge disposed within said fifth concavity of said first segment; and
a fifth shaped charge disposed within said fifth concavity of said second segment; wherein
said first void is operable to receive spall resulting from detonations of said fourth and fifth shaped charges.

15. The perforator of claim 1 further comprising:
a second concavity formed in a lower side of said second segment along a second radial offset from said first radial of said charge tube by an angle ranging between 5 and 180 degrees;
a circular third divider segment disposed within said charge tube below said second segment, said third segment having a first concavity formed in an upper side of said third segment along said second radial of said charge tube;
said second concavity of said second segment and said first concavity of said third segment together defining a second socket aligned with said second radial said charge tube;
a second opening formed through said charge tube centered at said second radial of said charge tube;
a second shaped charge disposed within said second socket; and
a second void formed between said second segment and said third segment.

16. A well perforator, comprising:
a hollow cylindrical carrier;
a first shaped charge disposed within said carrier;
a circular first segment having a first concavity formed along a first radial of said first segment, said first segment disposed within said carrier above said first shaped charge so that said first concavity of said first segment partially envelops a circumference of said first shaped charge;
a circular second segment having a first concavity formed along said first radial of said first segment, said first segment disposed within said carrier below said first shaped charge so that said first concavity of said second segment partially envelops a circumference of said first shaped charge; and
a first spall compartment formed between said first segment and said second segment operable to receive spall resulting from a detonation of said first shaped charge.

17. The perforator of claim 16 further comprising:
(i) a second shaped charge disposed within said carrier above said first segment;
a third shaped charge disposed within said carrier below said second segment; and
said first

Assignees

• Halliburton Energy Services Inc

Inventors

• Robey Richard E
• Hoelscher Christopher C

Classifications

• E21B43/117 Primary

  Shaped-charge perforators (E21B43/118 takes precedence) · CPC title

• E21B43/116

  Gun or shaped-charge perforators · CPC title