RU34718U1 - Cumulative charge - Google Patents

Description

Cumulative charge

The utility model relates to the field of explosive devices and can be used in perforation technology for perforating and blasting operations in the oil and gas industry, as well as in the mining industry, construction, and metallurgical production.

Currently in operation is a number of perforators designed for opening cased wells. The action of cumulative punchers of all types is based on the ability of a cumulative jet, formed when detonating a charge of explosive guns with a lined recess, to punch holes or channels in various obstacles.

A common element for all perforators is the cumulative charge, which uses the so-called cumulative effect, which gave the name to the entire family of perforators.

The design of the charge of cumulative perforators is subject to the requirements of high breakdown action with small overall dimensions and mass of explosives. The size of the charges is limited by the walls of the housing of the punch or individual shells and the size of the minimum allowable gap between the punch and the walls of the casing. The explosive mass should be minimal in order to reduce the detrimental effect of the explosion on the casing.

The charge shell, limiting the explosive, prevents the expansion of detonation products, increases the efficiency of the cumulative charge, increasing the size of the punched channel. For this, it is desirable that the shell material has a high density and low compressibility.

To achieve high efficiency of the cumulative charge, it is necessary to ensure the axial symmetry of all parts and charge assembly, the absence of gaps between the lining and the recess in the explosive checker, axisymmetric and complete initiation (Rifle-blasting equipment. Handbook / Edited by L.Ya. Fridlyander, M .: Nedra , 1990.S. 20-30).

The disadvantage of the charges of cumulative punchers of domestic production is the incomplete use of explosive energy, which leads to a decrease in the penetration depth of the barrier and an increase in the harmful effect of the punch on the casing.

A device is known - a charge for crushing oversized items, containing an explosive checker with a cumulative hemispherical recess, a metal recess lining, an initiation unit (see ed. Certificate of the USSR No. 189370, IPC F 42 V 1/02, 1967).

A disadvantage of the known device is that the charge with a hemispherical notch has a low efficiency on metal objects and increased requirements for the symmetry of initiation.

Also known is a cumulative charge, consisting of a body, explosive blocks with a cumulative recess, an initiation unit, a metal lining of the cumulative recess, very precisely centered on the same axis of symmetry with the initiation unit. The lining has the form of a part of the surface of a paraboloid or a hyperboloid of revolution and uniform thickness (see European Patent No. 0150241 of 09/12/1984, IPC F 42 B 1/02).

A disadvantage of the known device is the high requirements for the symmetry of initiation, as well as the fact that the impact on the object, due to the shape of the shock mass, is localized in a small area. This reduces the efficiency of crushing oversized.

The closest in technical essence to the proposed device is a cumulative charge containing a housing, an explosive charge placed therein with a cumulative recess formed by a conical surface, an initiation unit mounted on the end wall of the housing, and a cumulative lining (see patent RU No. 2065933, IPC E21 B 43/116, 1996).

A disadvantage of the known cumulative charge is the non-optimal form of the cumulative lining, which does not allow the formation of a cumulative jet with a supersonic penetration rate into the barrier.

The objective of the claimed utility model is to create a cumulative charge of increased breakdown ability by increasing the effective length of the cumulative jet.

The technical result achieved by the implementation of the claimed utility model is to increase the hydrodynamic quality of the punched channel - an increase in depth, uniformity of diameter and the absence of pestle.

This result is achieved due to the fact that in the cumulative charge containing the housing, the explosive charge placed in it with a cumulative recess formed by a conical surface, the initiation unit mounted on the end wall of the housing, and the cumulative lining forming the inner surface of the cumulative lining changes according to the law :

YBH AIXBH + BI,

3 ± 0.23 mm;

, 35 ± 0.335 mm;

XBH - coordinate along the axis perpendicular to the cumulative symmetry axis

lining, varies from 3.4 to 18.2 mm;

a forming the outer surface of the cumulative lining varies according to the law:

(Xn - Ar) + (YH - B2) R where:

AZ 237.83 ± 23.7 mm; Vg 86.13 ± 8.6 mm; R 250 ± 25 mm;

XH - coordinate along the axis perpendicular to the axis of symmetry of the cumulative cladding, varies from 4.2 to 19.5 mm; YH - coordinate along the axis of symmetry of the cumulative lining.

The diameter of the hole, as shown by theoretical and experimental studies, primarily depends on the shape of the charge with equal parameters of the lining. An increase in the thickness of the explosive charge layer compressing the lining contributes to an increase in the velocity of the cumulative jet and the diameter of the punched hole.

The implementation of the inner and outer surfaces of the cumulative lining according to the stated patterns makes it possible to obtain a cumulative lining with a variable wall thickness, while it is possible to slightly increase the thickness of the explosive charge layer without structurally changing the parameters of the cumulative charge. This contributes to obtaining a high-quality cumulative jet and the perforation channel pierced by it.

The essence of the utility model is illustrated by drawings, where: in FIG. 1 is a sectional view of a general view of a cumulative charge; in FIG. 2 schematically shows the cladding.

The cumulative charge comprises a housing 1, an explosive charge 2 with a cumulative recess 3 formed by a conical surface, an initiation unit 4 mounted on the end wall of the housing 1, and a cumulative lining 5. The generatrix of the inner surface 6 of the cumulative lining 5 changes according to the law:

, 3 ± 0.23 MM;

, 35 ± 0.335 MM;

XBH - coordinate of the no axis perpendicular to the cumulative symmetry axis

lining, varies from 3.4 to 18.2 mm;

YBH - coordinate along the axis of symmetry of the cumulative lining.

The generatrix of the outer surface of the cumulative lining 5 varies according to the law:

(x „- AZ) + (YH - B2) R

AZ 237.83 ± 23.7 mm;

B2 86.13 ± 8.6 mm;

R 250 ± 25 mm;

X „- coordinate along the axis perpendicular to the cumulative symmetry axis

facing, varies from 4.2 to 19.5 mm;

YH - coordinate along the axis of symmetry of the cumulative lining.

The cumulative charge works as follows. In the explosion of the initiation block 4, a detonation wave propagates through the explosive 2, upon exposure of which to the cladding 5 compression and deformation of the latter begins with the formation of a compact metal body of an oblong shape. Under the influence of a detonation wave and explosion products, this core begins to move, acquiring almost instantly high speed, and strikes a destructible object. Moreover, in the zone of impact, the products of the explosion also act actively on the volume, enhancing the destructive ability of the explosive device.

YBH - AIXBH + BI,

providing supersonic mode of penetration of the jet into the barrier. This mode of penetration ensures the interaction of the cumulative jet with an obstacle, which increases the amount of penetration.

As follows from the foregoing, the technical result, i.e. the increase in the hydrodynamic quality of punched perforation channels is ensured only if the implementation of all the essential features of the declared cumulative charge is interconnected.

Tests of the proposed cumulative charges made with the claimed design features have shown that the charges allow you to direct all the explosion energy to break the channel, minimizing the high-impact on the well, due to which the depth of the resulting perforation channels increases by 40-50% compared with existing charges.

Pestoobrazovanie from the material of the outer layer of the cladding and, accordingly, the deterioration of the quality of the punched channel in this case is excluded.

Claims (1)

A cumulative charge comprising a casing, an explosive charge placed therein with a cumulative recess formed by a conical surface, an initiation unit mounted on the end wall of the casing, and a cumulative cladding, characterized in that the generatrix of the internal surface of the cumulative cladding changes according to the law Y _vn = A ₁ · X _vn + B ₁ , where A ₁ = 2.3 ± 0.23 mm; In ₁ = -3.35 ± 0.335 mm; X _VN - the coordinate along the axis perpendicular to the axis of symmetry of the cumulative lining, varies from 3.4 to 18.2 mm; Y _ext - coordinate along the axis of symmetry of the cumulative lining, and the generatrix of the outer surface of the cumulative lining changes according to the law (X _n -A ₂ ) ² + (Y _n -B ₂ ) ² = R ² , where A ₂ = 237.83 ± 23.7 mm; B ₂ = 86.13 ± 8.6 mm; R = 250 ± 25 mm; X _n - the coordinate along the axis perpendicular to the axis of symmetry of the cumulative cladding, varies from 4.2 to 19.5 mm; Y _n - coordinate along the axis, the symmetry of the cumulative lining.