RU2369445C1 - Coating method and device - Google Patents

Abstract

FIELD: mechanics.

SUBSTANCE: high-speed flow of evaporant is produced by centrifugal force created by accelerating channels arranged on the drive axle. Aforesaid channels feature cross section narrowing from axle center to periphery. Accelerating channels can have generatrix arranged along hyperbolas. If accelerating channels are located in turbine wheel, its cross section decreases from the drive axle towards periphery. Coating is effected through narrowing accelerating channels by finely dispersed particles or gases with atomic weight exceeding that of phosphorus. Surface material is selected so that its interatomic distances exceed sizes of atoms or molecules of evaporant.

EFFECT: reduced power consumption and acceleration time interval.

4 cl, 3 dwg

Description

The invention relates to the field of technology for processing materials by coating in the form of fine particles or molecules on solid or elastic products. This method and device based on it are intended for applying heterogeneous coatings mechanically: particles of metal, plastic, ceramics, gases on the inner cylindrical surface of pipes, individual flat products, products of a different shape. The invention is intended for use in mechanical engineering, construction, repair and technical enterprises and other industries.

A known method of applying a cement-sand coating to the inner surface of the pipe (RF patent No. 2255816, 2003, B05D 7/22), in which the coating is applied using a rotating centrifugal head, in which the mixture is extruded from the tank body with the cement-sand mixture through the holes in the wall of the tank through the tubes out.

Known drive centrifugal spray head for applying a protective coating of cement-sand mixture to the inner surface of the pipe wall (RF patent 2272682, 2003, B05C 7/02).

This method and device use the acceleration of the mass flow by centrifugal forces arising from the rotation of the Central body of the vessel and the feed channels of the coating, for coating.

Using this device and similar other means it is impossible to obtain flows of particles or molecules of high speed (up to several hundred meters per second).

A known method of producing composite materials and coatings from powders and a device for its implementation (RF patent 2181788, 2000, IPC-7, C23C 24/04, 4/00, B05D 7/24). In this invention, a high-speed particle stream is organized by a gas-dynamic method to obtain composite materials from powder components on the surface of a substrate. When the gas-dynamic effect of the accelerated gas-powder flow in the nozzle on the substrate is initiated, the chemical interaction of the powder components of the exothermic composition is initiated, as a result of which a composite material is obtained, which can be separated from the substrate or stored in the coating.

A known installation for gas-dynamic coating of powder materials (RF patent No. 2181390, 2002). The invention is directed to obtaining coatings by gas-dynamic spraying on products of any geometric shape and size from various powder materials: metals and their alloys, ceramics, plastics.

The disadvantage of this method and device is the complex design and complex control system that requires high qualification of service. This method and device are environmentally hazardous, energy-consuming, use high pressure, are designed to work with powders, and not with gases.

The closest in technical essence of the claimed invention is a coating device (RF patent No. 2156170, 1996, B05B 7/22), based on the mechanical formation of a stream of material particles. The device contains booster channels, which can be located in the body of the turbine disk, a protective casing and a collection of technologically unused particles. Accelerating channels are located on the drive shaft of the device. In the middle part of the booster channels, a hole is made for supplying fine particles of the applied material. A dispenser and a hopper are sequentially combined with the hole. Along the perimeter of rotation of the acceleration channels, products, parts, etc., are installed on which a layer or layers of material are applied: reinforcing, anti-corrosion, abrasive, etc.

Thus, in this device, a high-speed stream of fine particles can be formed by centrifugal forces for coating metal, alloys, ceramics, plastic on metal surfaces, surfaces from alloys.

In this device, it takes a lot of time and energy to accelerate particles to the desired speed. The strength of the device is insufficient at high speeds.

The objective of the invention is to reduce the time to accelerate the turbine disk to the required speed, reduce energy consumption to accelerate the material to speeds above 500 m / s for coating surfaces of metals, alloys, ceramics and plastic. Another objective of the invention is its use for dispersing gases with an atomic weight greater than the atomic weight of phosphorus.

The problem is solved in that in a coating device in which a high-speed material flow is mechanically obtained by centrifugal forces, the cross-section of the acceleration channels decreases from the center to the periphery. This allows you to concentrate the bulk of the acceleration channels or turbine disk in their center, which reduces the acceleration time of the acceleration channels to the desired speeds, reduces energy costs for acceleration and increases the strength of the device.

The walls of the booster channels in longitudinal section may have the form of a hyperbola.

If the acceleration channels are located in the body of the turbine disk, the cross section of the turbine disk decreases from the center to the periphery.

It is recommended to choose the material of the surface of the product for coating during gas spraying so that the interatomic distances in it are larger than the sizes of atoms or molecules of the sprayed gas.

The universality of the proposed method and device is determined by the achieved maximum acceleration rate of the applied particles or gas molecules with minimum energy costs, minimum acceleration time and the strength of the device. A new proposed feature of the method is that the coating on the surface of the product is carried out with fine particles or a gas with an atomic weight greater than the atomic weight of phosphorus, and the material of the surface of the product is chosen so that the interatomic distances in it are larger than the sizes of atoms or molecules of the sprayed gas. The new proposed features of the device are: a constructive solution for accelerating channels, the cross section of which narrows from the axis of the drive to the periphery, while the longitudinal section of the channel can be made along a hyperbole, a constructive solution of the turbine disk, the cross section of which decreases from the axis of the drive to the periphery, as a result of which the main the mass of the disk is located in its central part.

These signs are not identified in other technical solutions when studying the level of this technical field and, therefore, the solution is new and has an inventive step

The drawings show a General view of the device for coating for implementing the method of coating.

Figure 1 - General structural view of the device for coating.

Figure 2 - accelerating channel with a cross section made on the hyperbole.

Figure 3 - a) a turbine disk with booster channels, b) a cross section of a turbine disk.

The coating device (Fig. 1) contains, as the main structural element, the acceleration channel 1. The acceleration channel 1 is mounted on the axis 2 of the actuator 3 (a symmetrical version is shown) in the form of a pipe tapering to the periphery and having a nozzle 4. Orthogonal to the axis channels 1 installed products 5, on which a coating layer of one or more materials is applied. Products of a more or less flat shape can be placed around the perimeter. The product may be a machined inner surface of the pipe.

A feeder 6 with sprayed material 7 and a dispenser 8 are installed above the central hole of the booster channel.

The acceleration channel 1 and the products 5 are placed in a dustproof casing 9. In the lower part of the casing 9 there is a collection 10 of raw material. A fan 11 is also located on the axis of the drive to purge the dust cover.

A longitudinal section of the booster channel 1 can be performed along a hyperbole (Fig. 2).

Accelerating channels 1 can be located in the body of the turbine disk 12 (Fig.3, a), the cross-section of which (Fig.3, b) decreases from the axis 2 of the drive 3 to the periphery.

The method is as follows.

Near the perimeter of the motion of the booster channel, articles (parts) are installed for applying a layer (s) of material on them, for example, a foreign alloy on a metal. Feeder 6 is filled with appropriate material. Then a high-speed drive 3 is launched. In this case, the material enters the acceleration channel 1. By centrifugal force, the material is accelerated to the design speed, and it comes into contact with the material of the surface of the articles 5 with significant dynamic pressure, where it is deposited.

To disperse gases with an atomic weight greater than the atomic weight of phosphorus, the technological units of the installation are placed in a vacuum chamber, and the surface material of the coating product is chosen so that the interatomic distances in it are larger than the sizes of atoms or molecules of the sprayed gas.

The type and quality of the compound depends on the acceleration rate of the particles, the pairs of materials used and a number of other external factors - the presence of oxidizing agents, dustiness.

At the same time, the basis for the high-quality deposition of layers and the range of material pairs is the particle velocity at the exit of the acceleration channel. The centrifugal principle of particle acceleration in terms of velocity is similar to gas-detonating coating and gas-dynamic spraying devices. In this case, particles of several microns can be accelerated up to 1000 m / s, and gases up to 2000 m / s. There are no restrictions on the thickness of the coating - it can have nanoscale, amount to only a few atoms.

For practical purposes, acceleration speeds up to 600 m / s are sufficient. In the proposed device, these speeds are achieved in a short period of time. Changing the geometry of the acceleration channels allows the drive to reach speeds of up to 100 thousand rpm and the size of the acceleration channels from 10 to 30 cm. In this case, cast iron, steel, nickel, cobalt, copper, aluminum, and all kinds of alloys can be used as products.

On various substrates, coatings of steel, cast iron, nickel, cobalt, copper, aluminum, all kinds of alloys, barium, chromium, titanium, nickel borides, iron, zirconium oxides, etc. are possible.

Using the claimed invention allows to simplify the design, reduce energy consumption, increase the strength of the device to conduct surface treatment with a high-speed stream of particles or gas to harden the surface, coating, changing the properties of the surface layer.

Claims (4)

1. A method for coating, including the mechanical formation of a high-speed flow of sprayed material on the surface of the product using centrifugal force generated in the accelerating channels, characterized in that the coating on the surface of the product is carried out with fine particles on any surface or with a gas with an atomic weight greater than the atomic weight of phosphorus on the surface of products whose material is chosen so that the interatomic distances in it are larger than the sizes of atoms or molecules of the sprayed gas, This high speed flow of the sprayed material is formed through the spreader channels, the cross section of which narrows from the center to the periphery. 2. The device for coating, placed in a vacuum chamber and containing accelerating channels placed in a horizontal plane relative to the vertical axis of the drive with axial holes for feeding the sprayed material to the surface of the products located around the circumference of rotation of the accelerating channels, as well as the feeder, dispenser, collection used material, a protective casing, characterized in that the acceleration channels are made symmetrically in the body of the disk having a uniform thickening from the periphery to the axis of the drive. 3. The device according to claim 2, characterized in that the cross section of the accelerating channels narrows from the center to the periphery. 4. The device according to claim 2, characterized in that the walls of the booster channels in longitudinal section are in the form of a hyperbola.

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