Patent Application
20150267515
1. Field of the Invention
The invention relates generally to the field of oil and gas production. More specifically, the present invention relates to a shaped charge system and/or gun body. Yet more specifically, the present invention relates to a perforating gun system that after detonation of its associated shaped charges minimizes wellbore gun fragments produced during well perforations. Also the gun system could be designed to disappear upon initiation, doing away with retrieval operations of hardware left downhole.
2. Description of Related Art
Perforating systems are used for the purpose, among others, of making hydraulic communication passages, called perforations, in wellbores drilled through earth formations so that predetermined zones of the earth formations can be hydraulically connected to the wellbore. Perforations are needed because wellbores are typically completed by coaxially inserting a pipe or casing into the wellborn, and the casing is retained in the wellbore by pumping cement into the annular space between the wellbore and the casing. The cemented casing is provided in the wellbore for the specific purpose of hydraulically isolating form each other the various earth formations penetrated by the wellborn. As is known, hydrocarbon bearing strata, such as reservoirs, exist within these formations. The wellbores typically intersect these reservoirs.
Perforating systems typically comprise one or more perforating guns strung together, these strings of guns can sometimes surpass a thousand feet of perforating length. Included with the perforating guns are shaped charges that typically include a charge case, a liner, and a quantity of high explosive inserted between the liner and the charge case. When the high explosive is detonated, the force of the detonation collapses the liner and ejects it from one end of the charge at very high velocity in a pattern called a “jet.” The jet penetrates the casing, the cement and a quantity of the formation.
Due to the high force caused by the explosive, the shaped charge and its associated components often shatter into many fragments, some that can exit the perforating gun into the fluids within the wellbore. These fragments can clog as well as damage devices such as chokes and manifolds thereby restricting the flow of fluids through these devices and possibly hampering the amount of hydrocarbons produced from the particular wellbore. Therefore, there exists a need for an apparatus and a method for conducting perforating operations that can significantly reduce fragmentation associated with perforating and thus minimize debris left behind.
A perforating assembly, comprising at least one perforating gun having a shaped charge comprising a charge case, a liner, and a main body of explosive. The components of the perforating gun may be comprised of an energetic material that disintegrates upon detonation of the shaped charge. The individual components include perforating guns (i.e. housing and gun tubes), shaped charges, shaped charge casing, and shaped charge liners. The material may be an oxidizer, tungsten, tungsten alloys, magnesium, magnesium alloys, cement particles, rubber compounds, compound fibers, KEVLAR®, steel, steel alloys, zinc, and combinations thereof.
With reference to the drawings herein,
The material may comprise an exothermic reactive material such as an oxidizer or Propellant. Examples of such exothermic reactive materials include ammonium perchlorate and potassium perchlorate, among others, as well as combinations of such compounds. The reaction of the material due to the shaped charge detonation effectively vaporizes the energetic material after the shaped charge detonation thereby eliminating the presence of post explosion debris from the components of the shaped charge 10.
Optionally, additives can be included with the energetic material, these include tungsten, magnesium, cement particles, rubber compounds, compound fibers, KEVLAR®, steel, steel alloys, zinc, and combinations thereof. Such additives can desensitize the energetic material to prevent an unplanned reaction of the material. Additionally, desensitizing additives can slow the rate of reaction of the state change of the energetic material thereby reducing localized pressure buildup during vaporization. These additives can also add strength to the energetic material. Desensitizing the material can be especially useful when the final product (i.e. the liner or charge case) is subjected to an environment that might promote early initiation of the material, such as high shock and or vibration, or an event that introduces excess temperature and/or pressure onto the material. Strength of material is important when the energetic material is used to form the shaped charge case 1.
Currently oxidizers are used in the production of subterranean hydrocarbons to create pressure in a hydrocarbon producing wellbore. Such an increase in pressure can be useful for stimulating a hydrocarbon bearing reservoir intersected by the wellborn. These oxidizers are usually in the form of a tube that is exposed to the wellbore and set off with a ballistic action that breaks up the material and burns which creates pressure in the wellbore.
With reference now to
The present invention described herein, therefore, is well adapted to carry out the objects and attain the ends and advantages mentioned, as well as others inherent therein. While a presently preferred embodiment of the invention has been given for purposes of disclosure, numerous changes exist in the details of procedures for accomplishing the desired results. For example, the invention described herein is applicable to any shaped charge phasing as well as any density of shaped charge. Moreover, the invention can be utilized with any size of perforating gun. It also should be pointed out that the apparatus herein disclosed is not limited to a shaped charge for use with a perforating pin, but can also include any type of ballistics shaped charge such as those shaped charges used in weaponry and ordinance related technology. These and similar modifications will readily suggest themselves to those skilled in the art, and are intended to be encompassed within the spirit of the present invention disclosed herein and the scope of the appended claims.
This application is a divisional of and claims priority to and the benefit of co-pending U.S. application Ser. No. 11/789,310, filed Apr. 24, 2007, which claims priority to and the benefit of co-pending U.S. Provisional Application Ser. No. 60/809,004, filed May 26, 2006, the full disclosures of which are hereby incorporated by reference herein in their entireties and for all purposes.
| Number | Date | Country | |
|---|---|---|---|
| Parent | 11789310 | Apr 2007 | US |
| Child | 14723124 | US |
