RU2384550C2 - Device for mixing components of explosive composition - Google Patents

Abstract

FIELD: explosives.

SUBSTANCE: device for mixing components of explosive composition includes upper and lower mixers with agitators and screws, a flow control device installed at the outlet hole of upper mixer, which includes two valves, the connection pipe of one of which is connected via mass line to the housing of upper mixer, and connection pipe of the second one is connected via mass line to the housing of lower mixer. Upper mixer includes two Z-shaped agitators installed perpendicular to the screw axis, mass line connected to the housing of upper mixer is included in the housing above front mixer by the value equal to 0.45-0.55 of the agitator's diametre and is located relative to upper part of front agitator at the height equal to 1.0-1.3 of the agitators' diametre. Each one of the mass lines is equipped with a heating jacket with individual heat carrier supply, and each valve is equipped with temperature and pressure sensor arranged in the valve cavity at the mass line inlet.

EFFECT: obtaining quality mixtures from explosive compounds owing to elimination of supercooling of the compound during its working.

3 dwg

Description

The invention relates to the field of manufacturing explosive compositions, in particular gunpowder and mixed solid rocket fuels.

The device can be used for the production of solid propellant engines of various classes of rockets, powder gas generators and other products of a similar purpose.

Known, for example, devices described in RF patents No. 2132837, No. 2164221, No. 2196760. They include the upper and lower mixers with mixers and screws and a set of continuously operating dispensers.

The disadvantage of these devices is that they are unprofitable in the conditions of manufacturing small batches of products and with frequent changes in explosive composition, as they require large expenses for the readjustment of continuously operating dispensers and cleaning of the supply lines of components in the upper mixer. In addition, the first portions of the composition coming out of the lower mixer may be substandard due to the composition being in a stagnant zone not captured by the mixers, for example, at the outlet of the upper screw.

One of the effective methods of mixing in the apparatus of chemical technology is the circulation mixing by repeatedly pumping the mixed composition through the apparatus.

In the patent of the Russian Federation No. 224702, adopted by the authors for the prototype, in the device for mixing the components of explosive compositions containing the upper and lower mixers there is a device for regulating the flow installed on the outlet of the upper mixer, equipped with two valves; the valves are equipped with hydraulic locking heads, the outlet pipe of one valve is connected to the upper mixer body, the pipe of the other valve is connected to the lower mixer body.

The use of this device at the FKP “Kamensky Plant” in Kamensk-Shakhtinsky showed the effectiveness of the circulating method of mixing, eliminated the need to eject the first portions of the processed composition, eliminated the need for a high-precision continuously acting dispenser on the feed line of the powdered component, demonstrated the expediency of using this device for manufacturing on high-performance equipment of small batches of products.

At the same time, work experience revealed flaws in the design of the device. Thus, the absence of heating on the lines connecting the valve nozzles to the mixers (mass pipelines) during stops leads to overcooling of the composition in them and, consequently, to the need for subsequent temperature adjustment in the mixers and an increase in the process time.

In addition, in the process of testing by experiment, the optimal parameters of the place of introduction of the mass pipe into the upper mixer were selected.

When the device was operated during cleaning with inert cleaning components by loading them into the top mixer with the working screws and mixers of both mixers, as well as alternating valve operation, there were cases of pressing of the cleaning composition in the valve area due to squeezing out of the composition of the liquid-viscous component or sub-optimal cleaning composition . In this case, with prolonged operation of the screw of the upper mixer and the absence of passage of the composition, dangerous overheating of it may occur.

The technical task of the present invention is:

- determination of the optimal input parameters of the mass pipe from the valve of the device for regulating the flow into the upper mixer;

- the introduction of mass heating pipes, connecting the valves of the flow control device with mixers;

- the introduction of control of the passage of the composition through the valve cavity.

The technical result is achieved by the fact that in the device for mixing the components of explosive compositions containing the upper and lower mixers with mixers and screws, a flow control device installed on the outlet of the upper mixer and comprising two valves, one of which is connected by a mass pipe to the upper case mixer, and the second pipe with the lower mixer housing, while the mass pipe connected to the upper mixer housing enters the housing above the front mixer by an amount equal to 0.45-0, 55 diameter of the mixer, the lower part of the outlet of the mass line is located relative to the upper part of the half-blade of the mixer at a height equal to 1.0-1.3 diameter of the mixer; each of the mass pipelines is equipped with a heating jacket with an individual supply of coolant; the cavity of the valves in the exit area of the mass lines are equipped with a temperature and pressure sensor.

The essence of the invention is illustrated by drawings, where figure 1 shows a General view of the device for mixing, figure 2 - view A of the device, figure 3 - view B of the device.

A device for mixing components consists of an upper mixer 1 (Fig. 1) with two, as a rule, mixers 2 mounted perpendicular to the axis of the screw, a Z-shaped design with two half-blades, and an unloading auger (drives of mixers and augers of the device are not shown), lower mixer 3 with mixers and auger, flow control device 4. The device is mounted on the flange 5 of the outlet of the upper mixer and is connected by the mass pipe 6 to the body of the upper mixer, and the mass pipe 7 is connected to the body of the lower mixer. Each of the mass pipelines is equipped with a heating jacket with an individual supply of coolant. The presence of individual heating jackets in the mass pipelines allows, for example, during long downtimes, to adjust the temperature of the composition in them separately, as applied to the temperature of each mixer, which, as a rule, differ from each other. The temperature in the mass lines can be determined based on the readings of the sensors installed in the valve cavities (figure 3). The mass pipe 6 enters the upper mixer housing by a value “a” equal to 0.45-0.55 of the diameter “d” of the mixer. The lower slice of the mass line is located at a height of "b" relative to the upper part of the mixer half-blade, which is 1.0-1.3 of the diameter of the stirrer.

The location of the device in plan is shown in figure 2.

Figure 3 shows a cross-sectional view of the valve of the flow switching device in the open position when the valve locking head 8 provides an annular gap for passage of the composition. The pipe 9 is designed to connect the mass pipe, and the sensor 10 for measuring temperature and pressure in the cavity of the valve. The pressure sensor is intended for comparative control of the pressure at the outlet of the auger of the upper mixer (the pressure sensor is not shown in the drawings) and the pressure at the inlet to the mass pipe, which makes it possible to determine the presence of emergency situations that can lead to an accident, for example, clogging of the train in the area of the locking head. The pressure sensor 10 is at the same time a temperature sensor (for example, a background sensor) and gives an indication of the temperature at the entrance to the mass pipelines.

The size “a” of the mass pipe entrance to the upper mixer is optimal, since in this case, the mixer actively moves the composition leaving the mass line into the active mixing zone.

Size “b” along the height of the mass pipe is chosen on the basis that, with a decrease in height, the loading volume of the upper mixer decreases, and with an increase in height above the indicated value, the upper part of the composition volume will not mix efficiently with mixers or even form a “roof” inaccessible for mixing.

The operation of the device for mixing components is as follows. Before loading components into the top mixer, both valves of the flow control device are closed. Liquid viscous and powdery components of the composition are loaded into the upper mixer, and the liquid viscous components are loaded ahead of time so that the non-wetted powder does not enter the auger zone. At the same time, the valve on the upper mixer opens, the mixers and the screw of the upper mixer are turned on. Simultaneously with the loading of the components, the composition begins to circulate in the upper mixer. After loading the components, the circulation of the compositions continues until they achieve a uniform distribution of the components and the required rheological characteristics.

Next, the valve of the lower mixer opens, the valve of the upper mixer closes, the mixers of the lower mixer are turned on and a set is made into the lower mixer, after which the screw of the lower mixer is turned on and the products are molded.

After developing the composition of both mixers, the cycle repeats.

Elements of the present invention worked out with a positive result when operating the device according to the patent of the Russian Federation No. 224702 at the Federal State Enterprise “Kamensky Plant” in Kamensk-Shakhtinsky.

Claims (1)

A device for mixing the components of the explosive composition containing the upper and lower mixers with mixers and screws, a flow control device installed on the outlet of the upper mixer, including two valves, one of which is connected by a mass pipe to the upper mixer body, and the second pipe is connected by a mass pipe with a lower mixer housing, characterized in that the upper mixer contains two Z-shaped mixers mounted perpendicular to the axis of the screw, a mass pipe connected to the housing m of the upper mixer, enters the casing above the front mixer by an amount equal to 0.45-0.55 of the diameter of the mixer and is located relative to the upper part of the front mixer at a height equal to 1.0-1.3 of the diameter of the mixers, with each of the mass pipelines equipped with a jacket heating with an individual supply of coolant, and each of the valves is equipped with a temperature and pressure sensor located in the cavity of the valve at the entrance to the mass pipe.

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