A perforating charge for use in sand control operations in oil and gas wells

Abstract

A perforating bullet for perforating and sand control operation of oil and gas well, comprising a bullet shell constituting a bullet body, a metal cup inside the bullet shell and a closure at the bottom of the bullet shell, and explosive for detonation filled between the bullet shell and the metal cup; characterized in that the bottom of the bullet shell is sleeved with a cup, and a medicament is filled in the independent space surrounded by the cup and the closure at the bottom of the bullet shell, the medicament being a mixture of strong alkali oxide and fluoride. The perforating operation with the bullet can rapidly solidify the surface of the perforating channel, effectively block the rapid sand production of the formation, and be favorable to the smooth implementation of subsequent sand control, sand consolidation operation and later production operation. The bullet has wide application range and achieves excellent sand control effect in wells or oil and gas layers with a depth of 800-1600 meters.

Description

Technical Field

[0001] This invention relates to the field of sand control perforation completion technology, and in particular to a perforation bullet for sand control operations in oil and gas well perforation. Background Technology

[0002] Traditional oilfield sand control technologies can be broadly categorized into three types based on the specific methods used: mechanical sand control, chemical sand control, and sand arching sand control. All three require perforation operations before sand control construction can proceed. A prominent problem in current perforation operations is that when encountering poorly cemented formations, especially layers dominated by clay, the loose cementation and relatively poor lithology often lead to continuous sand production within the perforated borehole. This severely impacts the progress and effectiveness of subsequent sand control construction, increases costs, and significantly affects oilfield production, resulting in a shortened production cycle and lower recovery rates. Summary of the Invention

[0003] In view of the above problems, the present invention provides a perforation bullet for sand control operations in oil and gas well perforation. Using the perforation bullet, a solidified body and a reaction layer can be effectively formed in the perforation channel, thereby slowing down or eliminating the situation of fine sand from the formation emerging along the perforation channel.

[0004] The technical solution of this invention is as follows:

[0005] A perforating projectile for sand control operations in oil and gas wells includes a projectile casing constituting the projectile body, a metal shaped charge liner inside the projectile casing, and a seal at the bottom of the projectile casing. Explosive for detonation is filled between the projectile casing and the metal shaped charge liner. The projectile casing is characterized by having a shaped charge liner fitted at its bottom, and an agent, which is a mixture of strong alkali oxides and fluorides, contained within the independent space formed by the shaped charge liner and the seal at the bottom of the projectile casing.

[0006] Furthermore, the metal shaped charge shroud is a shroud formed by pressing together metal powder and strong alkali oxide.

[0007] Furthermore, the strong alkali oxide in the pharmaceutical agent and the metal liner is calcium oxide, sodium oxide, or a mixture of the two; the fluoride in the pharmaceutical agent is sodium fluoride.

[0008] Furthermore, the agent is concentrated in a non-central area inside the medicated cover, near the top of the cover.

[0009] Furthermore, the depth of the oil and gas reservoir or well to which the perforating projectile is applicable is 800 to 1600 meters.

[0010] Using the perforation projectile of this invention for perforation operations can rapidly solidify the surface of the perforation channel, effectively preventing rapid sand production from the formation, which is beneficial for the smooth implementation of subsequent sand control, sand stabilization, and later mining operations. The perforation projectile of this invention has a wide range of applications and has achieved excellent sand control effects in wells or oil and gas formations at depths of 800–1600 meters. Attached Figure Description

[0011] Figure 1 This is a schematic cross-sectional view of the overall structure of the perforation projectile of the present invention.

[0012] Figure 2 This is a photograph of the propellant liner and the internal propellant 6 of the perforation projectile of the present invention.

[0013] Figure 3 This is a micrograph of the consolidation morphology on the surface of the perforation channel formed by the perforation projectile of the present invention.

[0014] 1. Cartridge casing, 2. Metal shaped charge liner, 3. Sealing, 4. Explosive, 5. Charge liner, 6. Explosive agent. Detailed Implementation

[0015] The technical solution of the present invention will be described in detail below with reference to the accompanying drawings.

[0016] like Figure 1 As shown, a perforating projectile for sand control operations in oil and gas well perforation includes a projectile casing 1 constituting the projectile body, a metal shaped charge liner 2 inside the projectile casing 1, and a seal 3 at the bottom of the projectile casing. Explosive 4 for detonation is filled between the projectile casing 1 and the metal shaped charge liner 2. The projectile casing 1 is characterized by having a shaped charge liner 5 fitted at its bottom. An agent 6, a mixture of calcium oxide, sodium oxide, and sodium fluoride, is contained within the independent space enclosed by the shaped charge liner 5 and the seal 3 at the bottom of the projectile casing. The agent 6 is concentrated in a non-central area near the top of the liner 5. Figure 1 , 2 (As shown).

[0017] The metal shaped charge shroud is a shroud formed by pressing together metal powder, calcium oxide, and sodium oxide.

[0018] This invention's perforating cartridge can be used with the Type 102, Type 127, and Type 178 sand-control perforators, meeting the requirements for 5.5in, 7in, and 9-5 / 8in casing operations. It allows for the combined application of different layers and perforators according to varying geological and engineering requirements. In over 20 wells already in use, the sand control success rate has reached 94%, with surface testing showing a sand content of less than 0.03% in the wells, no pump jamming, and all parameters fully meeting field operation requirements.

[0019] Taking a block in the Dagang Oilfield, which is a heavy oil sand-producing area, as an example, the formation permeability in this area is 249×10⁻⁶. -3 μm2 ~2964×10 -3 μm 2 Porosity 16.5%–26.1%, acoustic transit time 405 μs·m -1 ~485μs·m -1 The crude oil has a moisture content of 32%–74%, a clay content of 11.5%–27.1% (median particle size 0.21 mm), and a viscosity of 1.2 × 10⁻⁶. 4 It has a concentration of mPa·s, a freezing point of 13℃, and a density of 0.933 g·cm³. -3 .

[0020] The perforating projectile of this invention was used in perforation and sand control operations on 6 wells in this block. After the perforation operation, a consolidation surface was quickly formed on the surface of the perforated channel. Figure 3 As shown in the figure, it effectively prevents sand production. In the subsequent construction and production process, the average sand flushing and pump inspection cycle of the oil well was extended from the original 31 days to 158 days, an increase of 127 days, which improved the oil well production rate, proving that the sand control method of the perforation channel of the oil and gas well based on the perforation bullet of this invention is very effective.

[0021] The well described above, which used the perforating projectile of this invention for perforation combined with sand control operations, has an average well depth of 2460m, an oil layer location of 1480–1530m, an oil layer casing diameter of 139.7mm, a wall thickness of 7.72mm, a formation of porous, contact cemented formation, a sandstone grain size sorting coefficient of 1.51–1.65 with a median of 0.13–0.18mm, and a permeability of 1.12μm. 2 The porosity was 31.2%, the clay content was 8.66%, and montmorillonite accounted for 49.1%–67.5%. For comparison, four adjacent wells in the same area, operating in the same oil layer as the test well using this invention, only used ordinary perforation shells with sand control operations. After production, sand production was extremely severe, requiring multiple sand flushing and pump testing operations during production. In contrast, using the perforation shells of this invention for perforation sand control resulted in less than 0.02% sand content at the wellhead after perforation, with an average daily oil production of 28 m³ / s. 3 It is more than 2.6 times the production of neighboring wells that did not use this perforation sand control technology.

Claims

1. A perforating projectile for sand control operations in oil and gas well perforation, comprising a projectile casing constituting the projectile body, a metal shaped charge liner inside the projectile casing, and a seal at the bottom of the projectile casing, wherein explosive for detonation is filled between the projectile casing and the metal shaped charge liner; characterized in that: The bottom of the cartridge case is fitted with a propellant liner, and the independent space enclosed by the propellant liner and the bottom of the cartridge case contains a propellant, which is a mixture of strong alkali oxides and fluorides; the metal propellant liner is a liner formed by pressing metal powder and strong alkali oxides together.

2. The perforating projectile according to claim 1, characterized in that: The strong alkali oxide in the reagent and the metal liner is calcium oxide, sodium oxide, or a mixture of both; the fluoride in the reagent is sodium fluoride.

3. The perforating projectile according to claim 2, characterized in that: The medicine is concentrated in a non-central area near the top of the medicine cover inside the medicine cover.

4. The perforating projectile according to claim 1, characterized in that: The perforating projectile is applicable to oil and gas reservoirs or wells at depths of 800–1600 meters.

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