Apparatus and method employing perforating gun for same location multiple reservoir penetrations
AssigneeSaudi Arabian Oil Company
InventorAlwaleed Abdullah AL-GOUHI
Life of this patent
Estimating the term…
Abstract
Methods and apparatus are provided for conducting multiple successive same-location firings of a number of shaped charges carried by a perforating gun that is lowered into the wellbore and precisely positioned to align its charges with the penetration created by the first fired-charges in order to produce deeper and larger diameter penetrations that result in enhanced hydraulic fracturing of the reservoir and increased gas production from the completed well.
Claims20
(canceled)
A method of sequentially performing a plurality of perforations along a predetermined interval of a wellbore in a tight reservoir rock formation in order to deeply penetrate into the rock, the method comprising:
- a. securing a latch coupling to a length of casing at a predetermined position above and proximate to the interval to be perforated;
- b. lowering a gun that is secured to the downhole end of a latching tool into position adjacent the interval to be perforated;
- c. releasably engaging the latching tool with the latch coupling;
- d. firing a first series of charges from the gun to penetrate the reservoir rock along the interval with a first series of openings;
- e. pulling the latching tool upwardly in the wellbore to disengage the tool from the latch coupling;
- f. retrieving the gun from the wellbore, reloading the gun with fresh charges and returning the gun and latching tool to an engaged position with the latch coupling;
- and
- g. firing a second series of charges from the gun into the formation at the same locations as the first series to provide openings penetrating deeper into the formation than the first series of openings.
A method of sequentially performing a plurality of perforations at a predetermined interval of a wellbore in a tight reservoir rock formation in order to produce successively deeper penetrations into the rock, the method comprising:
- a. securing a latch coupling to a length of casing at a predetermined position above and proximate to the interval to be perforated;
- b. providing a perforating gun comprised of a plurality of sections where each section contains a plurality of shaped charges positioned in the same predetermined array and the arrays are axially and radially aligned with each other;
- c. securing the perforating gun to the downhole end of a supporting member;
- d. securing to the supporting member a plurality of latching tools that correspond in number to the sections comprising the perforating gun, the latching tools being spaced apart axially a distance that corresponds to the axial distance between the shaped charge arrays in the gun;
- e. lowering the first section of the gun into position adjacent the interval to be perforated;
- f. releasably engaging the latching tool with the latch coupling closest to the gun;
- g. firing a first series of charges from the gun to penetrate the reservoir rock along the interval with a plurality of openings;
- h. releasing the latching tool to disengage the tool from the latch coupling and lowering the gun to engage the adjacent latching tool with the latch coupling to position the second section of the gun adjacent the penetrations;
- i. firing a subsequent series of charges from the gun into the formation at the same locations as the first series to provide openings penetrating deeper into the formation than the first series of openings;
- and
- j. repeating steps (h) and (i) until all of the charges in the gun have been fired.
(canceled)
(canceled)
A method of sequentially performing a plurality of perforations at a predetermined interval of a wellbore in a tight reservoir rock formation in order to produce a large cavity for the introduction of hydrofracturing fluids, the method comprising:
- a. securing a latch coupling to a length of casing at a predetermined position above and proximate to the interval to be perforated;
- b. providing a perforating gun comprised of at least two sections, wherein a first section contains a plurality of n shaped charges, and wherein a second section contains a plurality of n−1 shaped charges, and wherein the charges in the at least two sections are axially and radially aligned with each other;
- c. securing the perforating gun to the downhole end of a supporting member;
- d. securing to the supporting member a plurality of latching tools that correspond in number to the sections comprising the perforating gun, the latching tools being spaced apart axially a distance that corresponds to the axial distance between the shaped charges in the first section;
- e. lowering the first section of the gun into position adjacent the interval to be perforated;
- f. releasably engaging the latching tool with the latch coupling closest to the gun;
- g. firing the charges of the first gun section to penetrate the reservoir rock along the interval with a plurality of n openings;
- h. releasing the latching tool to disengage the tool from the latch coupling and lowering the gun to engage the adjacent latching tool with the latch coupling to position the second gun section of the gun into a position such that the n−1 charges are targeted at the weakened rock remaining between each adjacent pair of openings of the n openings;
- i. firing the charges of the second gun section into the formation;
- j. retrieving the perforating gun;
- and
- k. removing the weakened and broken rock remaining from the firings
An apparatus for sequentially performing a plurality of perforations at a predetermined interval of a wellbore in a tight reservoir rock formation in order to produce a large cavity for the introduction of hydrofracturing fluids,
- the apparatus comprising a perforating gun containing a plurality of shaped charges, the perforating gun being releasably attached to the downhole end of an orienting tool, which orienting tool is secured to the end of a length of coil tubing or a wireline, wherein the orienting tool is configured to enter into secure releasable mating engagement with a corresponding receiving member that is secured to the end of a section of fixed well casing at a predetermined position above and proximate to the interval that is to be penetrated by the sequential firing of a plurality of shaped charges contained in the gun;
- the perforating gun being provided with a first series of n charges that are wired for an initial discharge at a first position and a second series of n−1 charges that are wired for a subsequent discharge at a second position, wherein the second position is such that the n−1 charges of the second series are positioned adjacent the rock remaining between the openings produced by the discharge of the first series of n charges.
Dependencies are inferred from the claim text.