RU29061U1 - DEVICE FOR APPLYING CARBON COATINGS ON THREADED MATERIAL - Google Patents

Description

DEVICE FOR APPLYING CARBON COATINGS ON THREADED MATERIAL

A utility model relates to the construction of an apparatus for producing carbon coatings on filamentary materials such as quartz filament, a bundle of silica fibers, etc. These carbon-containing filamentary materials, in turn, are used to obtain materials having conductive, heat-resistant, antiseptic and other properties.

A device for producing pyrolytic graphite on the surface of a quartz filament is known from German Patent No. 1646924, 80В 8/15, 1970. The device is a heat-resistant tube through which a quartz filament is pulled out from a glass block as a result of crimping by rolls and heating in an evil magnetic field. The specified quartz thread is additionally passed through a metal ring in which an electric field is indicated. As a result, the thread is additionally heated. At the same time, the filament is blown through the burner with a hydrocarbon-containing gas being supplied countercurrently to the reaction zone. As a result of pyrolysis of a gaseous hydrocarbon (for example, methane) in an inert atmosphere at temperatures of 1300 ° C, a carbon-containing coating forms on the surface of the quartz filament.

The disadvantages of this device for producing carbon-containing material are:

-high resistivity of the resulting carbon-containing coating (in the area of 30 cm about 400,000 OM);

- view temperature of the production process (about 1300 ° C), which leads to a loss of strength (up to 80%) of the quartz thread and a decrease in the already small relative deformation;

view complexity of the device and its low productivity. The closest analogue is the device described by RF patent No. 2100914, 1997 upon receipt of a resistive filiform material. The essence of the device lies in the fact that the thread, consisting of a bundle of silica) 1 monofilaments, is passed at a speed of 2-10 mm / s through a tubular reactor, inside which a temperature of 1000-1100 ° C is maintained. At the same time, with an speed of 0.5-3.0 l / min, an inert gas is fed into the reactor - nitrogen, previously passed through a container with a hydrocarbon liquid (kerosene, white spirit). As a result, a silica filament is coated with a pyrocarbon of a layered microstructure, and the material has a tensile strength of at least 8 kg, a specific linear resistance of 3-7 K / m and a spread of electrical resistance of no more than 8-10%.

The specified device has a number of significant disadvantages:

- a high process temperature of 1000-1100 ° C, which leads to a loss of elasticity and up to 40% - the strength of the silica warp of the thread, which limits its use;

-high variation in resistivity along the length of the thread of 8-10%, which is unacceptable for modern electrically conductive materials;

the low speed of the thread (not more than 10 mm / s) through the high temperature zone of the reactor, caused by the need to complete the reaction of formation and deposition of pyrocarbon, which leads to a low profitability of the process;

-high energy intensity of the process, due to the need to maintain high temperatures for a long time (due to the low speed of the thread);

low environmental / purity of the process due to the evaporation of gaseous hydrocarbons when they are fed into a tubular reactor; high complexity of the device and its low productivity (due to the low coating rate).

In connection with the foregoing, the technical task was set to eliminate these shortcomings, namely:

-decrease the process temperature by at least 300 ° C;

-to reduce the spread of resistivity along the length of the fiber no more than ± 5%;

-increase the speed of broaching fiber and thereby reduce the energy intensity of the process and increase its profitability;

-improve the environmental friendliness of the production method by eliminating the evaporation of gaseous hydrocarbons when they are fed to the reactor;

-to simplify the installation design.

The technical result is achieved in that in a device for producing a carbon-containing material, first a preliminary dissolution is carried out in a hydrocarbon solvent of a ferrocene-containing catalyst with a concentration of 0.51.0 wt.%, Then a thread or a bundle of fibers is wetted or soaked in the specified solution, followed by feeding it with at a specified speed of 12-15 mm / s to the pre-flush zone up to 400 ° C, in the middle of which an inert gas - nitrogen is fed through a special input in a direction perpendicular to the five or beam silica thread. After preheating the filament or bundle, they are fed into the zone of net pyrolysis of the hydrocarbon at a temperature of 750-800 ° C, followed by removal of the filament from the zone, cooling and winding on a drum.

allowing, to set the speed of the thread broaching, as the thread is rolled from the coil, its axis of symmetry is stabilized using a spring mechanism (3), after which the thread enters the bathroom (4), in which there is a hydrocarbon solvent with a ferrocene-containing catalyst previously dissolved in it. In this bath, the thread or the bundle is wetted or soaked with solution. Next, the thread or bundle enters the reactor (5), which is an insulated casing with two temperature zones. The first zone of preheating the filament to 400 ° C and the second a1-cohesive pyrolysis zone of 750-800 ° C. A quartz tube with a diameter of 4 mm is installed inside the reactor, which is connected to a special inert gas (nitrogen) inlet (6), which is located in the middle of the heating zone of the filament, beam and allows the inert gas to be introduced from the cylinder (7) perpendicular to the movement of the filament and bundle at a speed of 1 5 l / min.

The length of the reactor core is 400 mm, and the heating zone is 300 mm. The temperature in the zones of the reactor, as well as in the furnace, was recorded and controlled using thermocouples and potentiometers grouped into control units (8).

The problems solved by this utility model are achieved in that the first stage of applying carbon coatings is in the form of a sealed bath (4), which allows the impregnation or wetting of the filamentary material coming from the coil (1). The axis of symmetry of the thread smoothly changes as the filamentary material is wound with the help of a spring element (3), and also due to the fact that the impregnating material is a solution of a ferrocene-containing catalyst with a hydrocarbon solvent selected from the series: kerosene, white spirit.

In addition, the reactor (5) is made in the form of an insulated body with two temperature zones separated: the first zone for preheating the filamentary material to 400 ° C has a length of 300 mm, the second zone of active pyrolysis of hydrocarbon at 750-800 ° C has a length of 400 mm. In this case, the filamentary material is pulled through a quartz tube, which passes through these two zones.

A search conducted on patent technical literature showed that the claimed combination of distinctive features is unknown, i.e. it meets the condition of patentability “novelty.

Since the claimed utility model is made from known components, it meets the patentability condition “industrial applicability.

Below is an example of the operation of the device for applying a carbon coating on a thread in the form of a bundle of silica fiber manufactured by the domestic industry of the K-11sb-180 (TU 6-48-52-80) brand with a linear density of 180 tex. : Example 1.

obtaining carbon-containing material. In this case, the silica yarn was subjected to the following processing steps:

- Impregnation of the filament in the bathroom at room temperature in a 0.6% solution of ferrocene in kerosene, which was previously prepared in a paddle mixer.

- Pulling the thread through an insulated tubular reactor made of quartz glass with a length of 700 mm and an inner diameter of 4 mm, which is divided into temperature zones. The first zone of preheating the filament to 400 ° C was 300 mm, in the middle of which nitrogen gas was supplied through the nozzle at a rate of 1.5 l / min. The feed was perpendicular to the movement of the thread. The second zone of active pyrolysis at a temperature of .750 ° C was 400 mm.

As a result of the set of physicochemical processes at all stages of processing, a carbon-containing material with a strength of 12 kg with a relative elongation of 3%, which had an electrical resistance of 5 K / m with a spread of its values along the length (in sections of 1 m), did not exceed ± 5%.

Strength and elongation were measured by a standard method on an Instron. Measurement of electrical resistance was carried out in the area of the thread 1 m standard ohmmeter. The resistance values and its scatter were assigned from 10 measurements.

Thus, the proposed utility model of a device for producing a carbon coating on the surface of a filamentary material allows you to:

1. Significantly, reduce the pyrolysis temperature by more than 300 ° C;

2. Observe the uniformity of the electrical conductive properties along the length of the fiber (the deviation was not more than ± 5%);

3. To obtain a carbon-containing material based on silica fibers with a specific resistance of 3-5 Kom / m and high physical and mechanical characteristics: tensile strength of 10-12 kg with a relative elongation of 5-3%;

4. Improve the environmental / cleanliness of the process.

The obtained technical results could not be predicted or calculated in advance, since for the first time in the installation for applying carbon coatings on filamentary material, original devices were used that effectively implement multi-stage processing modes with different temperatures, gas-vapor, catalytic media differing in their physicochemical nature, having complex mutual influences on each other.

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Claims (2)

1. A device for applying carbon coatings to a filamentary material, including a thread-pulling mechanism, equipped with a spring compensating element, a sealed bath for impregnation, wetting of the filamentary material in a catalyst solution in a hydrocarbon solvent, an reactor in the form of an insulated body with two temperature zones separated, the first of which is preliminary heating temperatures to 400 ° C has a length of 300 mm, and the second zone of active pyrolysis of hydrocarbon solvent at 750-800 ° C has a length 400 mm, while the housing contains inside a quartz tube with a diameter of 4 mm, which passes through these two temperature zones and has an inert gas inlet in the middle of the heating zone. 2. The device according to claim 1, where a solution of ferrocene 0.5-1.0 wt.% In a hydrocarbon solvent selected from the series: kerosene, white spirit is used as an impregnating material.