Firing head assembly, well completion device with a firing head assembly and method of use

Patent metadata

Field	Value
Publication number	US-11193358-B2
Application number	US-201816225299-A
Country	US
Kind code	B2
Filing date	Dec 19, 2018
Priority date	Jan 31, 2018
Publication date	Dec 7, 2021
Grant date	Dec 7, 2021

Abstract

A firing head assembly for use with a perforating gun is described. The firing head assembly includes a tubular housing, first and second pistons, and a compressible member arranged within a lumen of the tubular housing and positioned between the first and second pistons. According to an aspect, the assembly includes a plurality of upper locking arms and lower locking arms that engage with locking members formed in the tubular housing. The firing head assembly further includes upper and lower shear washers arranged at the second opening of the tubular body, in a sandwich type configuration with respect to the second piston. Pressures within the firing head assembly may be adjusted to activate the firing head assembly to either trigger an explosive reaction or to not trigger the explosive reaction.

First claim

What is claimed is:

1. A firing head assembly, comprising:
a tubular housing having a first end, a second end, and a lumen extending between the first end and the second end;
a first piston and a second piston positioned at least partially within the lumen, wherein the first piston is positioned proximate to the first end of the tubular housing and is slidably moveable within at least a portion of the lumen, and the second piston is positioned proximate to the second end of the tubular housing and is slidably moveable within at least a portion of the lumen;
a compressible member arranged within the lumen of the tubular housing, the compressible member comprising a first end portion and a second end portion, the first end portion abutting the first piston and the second end portion abutting the second piston;
a plurality of upper locking arms and a plurality of lower locking arms, wherein each locking arm is configured to engage with respective locking members positioned within the tubular housing;
an upper shear washer and a lower shear washer, wherein the upper and lower shear washers are arranged adjacent to the second end of the tubular body in a spaced apart configuration with respect to each other; and
at least one of:
a firing pin positioned below the second piston, and a percussion initiator positioned below the firing pin; and
an electric contact pin positioned below the second piston, and an electric circuit board positioned below the electric contact pin, wherein

the first piston and the tubular housing at least partially define an upper chamber of the lumen above the first piston, the upper chamber having a first pressure,
the second piston and the tubular housing at least partially define a lower chamber of the lumen below the second piston, the lower chamber having a second pressure, and
the compressible member is in an intermediate chamber of the lumen disposed between the upper chamber and the lower chamber.

2. The firing head assembly of claim 1 , wherein:
the upper locking arms are coupled to the first piston; and
the lower locking arms are coupled to the second piston.

3. The firing head assembly of claim 1 , further comprising one of:
at least one port that fluidly connects the lower chamber to the wellbore pressure outside the tubular housing, so that the second pressure is the same as the wellbore pressure; and
at least one port that fluidly connects the upper chamber to the wellbore pressure outside the tubular housing, so that the first pressure is the same as the wellbore pressure.

4. The firing head assembly of claim 1 , wherein:
an increase of the first pressure moves the first piston and the upper locking arms downwardly towards the upper slot and compresses the compressible member to a partially compressed state; and
a decrease of the wellbore pressure outside the tubular housing and respectively the second pressure of the lower chamber coupled with the partially compressed state of the compressible member, is operative for breaking the lower shear washer, thus allowing
the firing pin to move downwardly to strike the initiator and trigger an explosive reaction, or
the electric contact pin to move downwardly to strike the electric circuit board to trigger the explosive reaction.

5. The firing head assembly of claim 1 , wherein:
an increase of the first pressure moves the first piston and the upper locking arms downwardly towards the upper slot and compresses the compressible member to a partially compressed state; and
an increase of the wellbore pressure and respectively the second pressure of the lower chamber is operative for breaking the upper shear washer, moving the second piston and the lower locking arms upwards towards the lower slot, and compressing the compressible member until the lower locking arms engage in the lower slot so that the firing head assembly can be retrieved from the wellbore without triggering an explosive reaction.

6. The firing head assembly of claim 1 , wherein the second pressure is adjusted by at least one of:
moving the firing head assembly upwardly or downwardly in the wellbore; and
adding a fluid to or removing at least some fluid from the wellbore, where the fluid comprises at least one of nitrogen, drilling fluid, water and completion fluid.

7. A well completion device comprising:
a perforating gun; and
a firing head assembly, comprising:
a tubular housing having a first end, a second end, an inner wall, a lumen bound by the inner wall and extending between the first end and the second end, and a plurality of locking members positioned in the lumen;
a first piston and a second piston, wherein the first piston is adjacent the first end of the tubular housing and the second piston is adjacent the second end of the tubular housing, and each of the first piston and the second piston slidably extends into the lumen;
a compressible member arranged within the lumen of the tubular housing, the compressible member having a first end portion abutting the first piston, and a second end portion abutting the second piston; and
a plurality of upper locking arms and a plurality of lower locking arms, wherein each of the locking arms is configured to engage with one of the locking members, wherein
the first piston and the tubular housing at least partially define an upper chamber of the lumen above the first piston, the upper chamber having a first pressure,
the second piston and the tubular housing at least partially define a lower chamber of the lumen below the second piston, the lower chamber having a second pressure,
the compressible member is in an intermediate chamber of the lumen disposed between the upper chamber and the lower chamber, the intermediate chamber having a third pressure comprising atmospheric pressure, and
the firing head assembly comprises at least one sealing member positioned between the first piston and the lumen of the tubular housing, and at least one other sealing member positioned between the second piston and the lumen of the tubular housing, wherein the sealing members isolate the third pressure from the first pressure, the second pressure and a wellbore pressure outside the tubular housing.

8. The well completion device of claim 7 , further comprising:
at least one port that fluidly connects the lower chamber to the wellbore pressure outside the tubular housing, so that the second pressure is the same as the wellbore pressure.

9. The well completion device of claim 7 , further comprising one of:
a firing pin positioned below the second piston, and a percussion initiator positioned below the firing pin in a spaced apart configuration, wherein the firing pin is for applying a downward force to the initiator to trigger an explosive reaction; and
an electric contact pin positioned below the second piston, and an electric circuit board positioned below the electric contact pin in a spaced apart configuration, wherein the electric contact pin is for contacting the electric circuit board to trigger the explosive reaction.

10. The well completion device of claim 9 , wherein:
an increase of the first pressure of the upper chamber is operative for moving the first piston downwardly towards the second piston and moving the upper locking arms downwardly to the upper locking member, so that the upper locking arms are secured to the upper locking member and the compressible member is in a partially compressed state; and
a decrease of the wellbore pressure outside the tubular housing and respectively the second pressure of the lower chamber is operative for breaking the lower shear washer, wherein breaking the lower shear washer allows the firing pin to move downwardly to strike the initiator and tri

Assignees

• Dynaenergetics Gmbh & Co Kg
• DynaEnergetics Europe GmbH

Inventors

• Preiss Frank Haron

Classifications

• E21B43/11852 Primary

  hydraulically actuated · CPC title

• E21B34/10

  operated by control fluid supplied from outside the borehole · CPC title

• E21B43/1185 Primary

  Ignition systems · CPC title

• E21B23/04

  operated by fluid means, e.g. actuated by explosion (E21B23/08 takes precedence) · CPC title

• E21B23/042

  using a single piston or multiple mechanically interconnected pistons · CPC title