RU2451003C1 - Extrusion machine for processing of ballistite gun powders and fuels - Google Patents

Abstract

FIELD: machine building.

SUBSTANCE: invention represents extrusion machine the actuating element of which is made in the form of two rotors arranged in open housing on parallel shafts with a gap excluding the contact in gear between opposite surfaces. Curved wedge gaps decreasing in the direction of rotor rotation are located between inner side surfaces of housing and outer cylindrical surfaces of rotors. Housing is closed along end faces with cover plates tightened with dynamically loosened pins. Gear pair providing rotor synchronous rotation is arranged between rotors and drive.

EFFECT: improved safety during manufacture of ballistite gun powders and fuels in homogenisation and pressing phases.

3 dwg

Description

The invention relates to equipment for the production of ballistic defects and fuels, and in particular to equipment for the phases of homogenization of the powder mass and pressing charges.

The extruder can be used in the production of ballistic powders and fuels of any type at these phases, including highly filled ones with powerful explosives (such as HMX, RDX) and combustion catalysts.

A known device used for the homogenization of gunpowder and fuels are rollers, the essence of which is described in the book of L. A. Smirnov “Equipment for the production of ballistic gunpowder by screw technology and charges from them”, M., 1997, p.95- 107.

The rollers have two cast-iron hollow rolls with a diameter of 550 mm and a length of 1400-1450 mm, located in the horizontal plane. The disadvantages of using rollers for processing the above-described powders and fuels are high shear stresses arising in the compositions, leading to their heating and, as a consequence, thermal decomposition, destruction of cellulose nitrates, and a decrease in physical and mechanical strength. Often this is accompanied by sunbathing with a loss of 40-50 kg of expensive fuel, the occurrence of a serious danger to maintenance personnel and the failure of equipment.

The closest analogue to the prototype of the present invention is a screw press, the design and operation of which are described in the aforementioned book of L. A. Smirnov on p. 72 and 114-117. It consists of a steel case with a dynamically weakened bronze sleeve pressed into it, in which the screw-screw rotates. At the outlet, a forming grid is attached to the housing if the screw press is used as a homogenizer. The process of the flow of the powder mass is conventionally divided into four technological zones along the length of the screw screw: loading, plastic deformation of the powder mass, homogenization and pressing.

The disadvantage of the prototype is that in the screw press in a closed state there is a volume of gunpowder, which has great destructive potential and danger for working people, as well as a dynamically weakened sleeve, designed to eliminate the explosion, being structurally complex, is very expensive to manufacture, while the strength calculation its characteristics are not verified by field tests. The mass flow coming down from the screw has an uneven velocity diagram with a pulsating character, which in some cases makes it difficult to create a safe continuous process.

The problem to which the invention is directed is to develop a device capable of performing the operation of homogenizing a granular powder mass at a temperature of its plastic deformation, to provide pressure for molding an extrudate of a given geometric shape with an increased level of safety of the whole process.

The technical result of the invention consists in developing the design of an extruder that provides the processing of ballistic powders and fuels of any type, including highly filled with powerful explosives (such as HMX, RDX) and combustion catalysts.

To achieve the stated result, it is proposed to perform the extruder according to the principle of a gear pump. The working body is proposed to perform in the form of two rotors located in an open housing mounted on parallel shafts with a gap that excludes contact in the gearing. Between the inner side surfaces of the housing and the outer cylindrical surfaces of the rotors are made curved wedge gaps, decreasing in the direction of rotation of the rotors. At the ends, the casing is closed by covers pulled through it by dynamically weakened studs. Outside the housing, a parallel gear set is mounted on the parallel shafts. One of the wheels of the pair is a drive mounted on a shaft connected to the drive. The pair provides synchronized rotation of the rotors. A forming tool is attached to the bottom of the housing.

The essence of the proposed extruder is illustrated by drawings, where in Fig.1 shows a cross section of the extruder, in Fig.2 is a top view of the extruder, in Fig.3 is the gearing of the rotors.

The extruder includes a housing 1 (Fig. 1), two gear rotors 2 mounted on parallel shafts 3. A hopper 4 is installed at the top of the housing, and a removable forming tool 5 is installed at the bottom. The extruder is mounted on the frame 6. Curved between the rotors 2 and housing 1 wedge gaps "A", decreasing in the direction of rotation of the rotors. The housing 1 at the ends is closed by covers 7 (Fig. 2), pulled through it by dynamically weakened studs 8. Outside the housing, on the parallel shafts there is a gear pair 9, one of the wheels of which is leading. Figure 3 shows the gearing of the rotors.

The device operates as follows. Gunpowder in the form of granules, heated to the required temperature, enters the hopper 4 (Fig. 1) and from it by gravity to the housing 1, where the granules fill the hollows of the rotors 2 and the beginning of the curved wedge gaps "A". This is the download area. Rotating rotors capture the granules and carry them into the gaps "A", where the granules are compressed and their plastic deformation. With further rotation, the powder mass falls into the zone “B” of complete homogenization, located between the beginning of the gearing of the rotors 2 and the forming tool 5. In this zone, the flow of mass flows sequentially, expanding and tapering in cross section with a large amount of shear deformations. The homogenization process in the forming tool is ending.

According to pre-developed programs, experimental research was carried out at FSUE NIIPM in order to determine safe conditions and operating modes of the extruder. The identified boundaries of the values of design parameters were used in the development of technical documentation. An extruder is being manufactured.

Claims (1)

An extruder for processing ballistic powders and fuels, including a housing, a working body, a forming tool, a frame and a drive, characterized in that the working body is made in the form of two rotors placed in an open housing on parallel shafts with a gap that excludes contact in the gearing between opposite surfaces and curved wedge gaps between the inner side surfaces of the housing and the outer cylindrical surfaces of the rotors, decreasing in the direction of rotation of the rotors, while the housing the ends are closed by covers pulled through it by dynamically weakened studs, and a gear pair is installed outside the housing on parallel shafts, one of the wheels of which is leading.

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