RU2534661C1 - Cumulative charge - Google Patents

Abstract

FIELD: weapons and ammunition.

SUBSTANCE: charge includes a housing with a stick BB and hollowness in the form of open tulip. Lining has acute-angled conical end made from a mixture of powder metals mated to metal base. The form of side base surface is formed by arc rotation around axis, and an angle between the tangent to arc in the place of connection to the end and charge axis is (78±7)°.

EFFECT: improving quality of producing reservoir opening while forming expanding cumulative channel in deposit rock.

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Description

The invention relates to oil and gas production, in particular to a device for the cumulative charge of a downhole perforator, which creates an expanding cumulative channel when opening a reservoir.

Known cumulative charge (1) with a lining, which contains three conical sections and is formed from a mixture of powder metals. The height of the first two sections in the axial direction is 30-70% of the total height of the cladding. The first conical section has an angle of inclination of 20-60 °. The second conical section has a larger angle of inclination, which is in the range of 30-70 °. The third conical section is formed from a material that has a density lower than the material of the first and second sections. The inclination angle of the third section is greater than the inclination angle of the first section and equal to or less than the inclination angle of the second section.

A disadvantage of the known construction is the insignificant effect of the geometric parameters of the lining on the configuration of the channel formed in the rock, since the local thickening of the jet, obtained by pushing one part of the jet over the other, is triggered on the first sealing barrier and does not affect the channel profile.

Known cumulative charge (2), the lining of which is made of two different materials. After the charge is triggered, successive jets are formed, the nature of the impact of which on the obstacle is different. A known charge has the same drawback as the previous one; due to the pestle of the upper part of the cladding being pushed onto the pestle of the lower part, a large-diameter hole is formed in the first barrier - the perforator case, thereby consuming the energy of the explosive bomb (BB) of the charge.

The cumulative charge and lining for the cumulative funnel of this charge are known (3). The device contains two claddings, which are installed coaxially in the housing. The primary lining is equivalent to the standard cumulative charge lining, which serves to form a large hole. Impact lining is installed at the apex of the primary one and upon detonation of the charge provides the formation of an advanced high-speed cumulative jet, which opens the way for the main shock jet through the borehole fluid in which the charge is used. The known device has a drawback: it is effective enough to form a large hole in the well string, but ineffective to form an expanding channel in the productive rock.

Closest to the proposed device is the design of a cylindrical cumulative charge with a tulip-like lining of metal (4, prototype). The charge lining forms a high-speed nose of the jet, emitted from a relatively short acute-angled part at the top of the lining, and the main jet following it at a distance, emitted from the relatively extended massive part of the lining base adjacent to the apex with a raster angle between generators close to the right angle. Moreover, the transition between the parts of the cladding is made in the form of a short almost stepped neck.

The disadvantage of the prototype is the formation of a massive metal pestle, which negatively affects the technology of opening - clogs the channels, in addition, the lining is able to create a large hole in the column, but is not able to create an expanding channel in the rock.

The technical result of the invention is the creation of a device that improves the quality of work and reduces costs when opening a productive reservoir with the creation of an expanding cumulative channel in the formation rock.

The necessary technical result is achieved by the fact that in the cumulative charge, including the body, the explosive saber with a cumulative recess in the form of an opened tulip and a composite cladding consisting of a conical top connected to the base of the cladding with the shape of the side surface formed by the rotation of the arc around the axis, an acute-angled conical top usually made of a mixture of powder materials, the base is made of metal, and the angle between the tangent to the arc at the junction with the apex and the axis of the charge I in the range of (78 ± 7) °.

A comparison of the proposed technical solution with the prototype allows, in the opinion of the author, to establish compliance with its criterion of "novelty."

The author does not know the use of the combination of distinctive features of the device in other areas of technology, which gives reason to believe that the proposed solution meets the criterion of "inventive step" and is industrially applicable.

Figure 1 shows an embodiment of the charge. The charge includes a housing 1 with a saber BB 2 with a cumulative recess in the form of an opened tulip. The lining has an acute-angled conical vertex 3, joined with the base of the lining 4. The shape of the side surface of the base is formed by the rotation of the arc around the axis, and the angle α between the tangent to the arc and the axis of the charge is made in the range (78 ± 7) °.

Figure 2 shows the relative position of the parts of the composite cladding when the charge is triggered. An acute-angled conical apex forms a cumulative stream 5, the base of the cladding with the indicated geometric parameters forms a sleeve 6. In the annular space 7, limited by the dashed line, the pressure of the detonation products is comparable to the detonation pressure in the explosive block. Due to this pressure, the metal sleeve acquires a lateral impulse and expands when it penetrates into the formation rock. It should be noted that the existing powder compositions are of little use for the manufacture of the base of the cladding, since in the state of the jet they are not a solid impenetrable body that can hold high pressure in the annular space (7).

Figure 3 shows the channel 8, which is created by the charge in the rock of the reservoir 9; the case of the perforator 10, the borehole fluid 11, the casing 12 and cement stone 13. The maximum expansion of D _{to max} falls on the peripheral zone of the channel. Channel after lumbago fills "porridge" 14 from finely divided rock, which is easily removed with minimal depression. Pest from the metal base of the cladding is not formed.

Dotted line 15 indicates the zone of maximum expansion of the channel, which creates charges - analogue (3) and prototype (4).

Information sources

1. Facing for a cumulative charge. Patent US 6840178 BB dated 02.21.2003.

2. The cumulative charge. Patent DE 10129227 A1 dated 03/14/2002.

3. The cumulative charge and lining for the cumulative funnel of this charge. Patent EP 1345003 A3 dated 05/12/2004.

4. Cylindrical cumulative charge with a tulip-like lining. Patent DE 3622680 A1 dated 01/14/08 (prototype).

Claims (1)

A cumulative charge, comprising a housing, an explosive checker with a cumulative recess in the form of an opened tulip and a composite cladding consisting of a conical top connected to the base of the cladding with the shape of the side surface formed by the rotation of the arc around the axis, and the acute-angled peak is made, as a rule, of a powder mixture materials, the base is made of metal, and the angle between the tangent to the arc at the junction with the apex and the axis of the charge is in the range (78 ± 7) °.

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