SU1706716A1 - Device for application of coatings to internal surfaces of articles - Google Patents

Abstract

The invention relates to a device for coating internal surfaces and can be used in mechanical engineering for strengthening and repairing machine parts. The aim of the invention is to improve the quality of the coating and the productivity of the work. For this, each screen element is provided with a heating device, and the diameter of the lower base of the previous screen element is made smaller than the diameter of the upper base of the subsequent element. The angle of the end of each element is selected from the ratio / One dnc p arctg (-). where g) ps, dnp are the diameters of the upper bases of the subsequent and previous conical elements, mm; a is the distance between them, mm. In this case, the material particles are thrown off strictly perpendicular to the sprayed surface. By reducing the screen cleaning time, the sputtering performance is improved. 3 il. And f

Description

The invention relates to a device for coating internal surfaces and can be used in mechanical engineering for strengthening and repairing machine parts.

The aim of the invention is to improve the quality of the coating and the productivity of the work.

FIG. 1 shows the device, a general view; in fig. 2 - screen layout; in fig. 3 is a section A-A in FIG. 2,

The device contains a spray gun 1, a mounting device in the form of a carriage 2 with a guide 3 and a rotating screen 4 made as a set mounted on an axis 5 with an offset of elements 6 and 7, the first of which along the path

the coverings are conical 6, and the rest are made in the form of truncated cones 7 with internal through cavities 8 for the passage of gas. Each element 6 and 7 of the screen 4 is provided with a heating device 9, made, for example, of a material with a high resistivity and connected by means of wires 10 through the landborne device 11 to a power source (not shown). The diameter of the lower base of the previous element 7 of the screen 4 is smaller than the diameter of the upper base of the subsequent element 7.

The angle of the cone of each element is chosen from the ratio

fClnc dnp

WITH

about"

about

/ 7 arctg (2a

where dnc, dnp are the diameters of the upper bases of the subsequent and previous conical elements 7;

and is the distance between the elements.

The spray gun 1 and the screen 4 are mounted with the possibility of reciprocating motion along the guides 3 of the carriage 2, the screen is rotated by the drive 12. The article 13 is mounted on the supports 14 and fixed by the clip 15.

The device works as follows.

During the spraying of the coating on the inner surfaces of the product 13, the latter is fixed on the supports 14 by a clamp 15. Screen 4 is inserted into the cavity of product 13. Install screen 4 and spray head 1 along the axis of the cavity of product 13. The distance between spray head 1 and screen 4 is determined according to the formula b I - g, where b is the distance from sprayer 1 to the top of the cone 6; I — spraying distance; d is the radius of the inner surface of the product 13. The current source is turned on and the screen elements 6 and 7 are heated with the help of a heating device 9. The screen rotary actuator 12 is turned on, and then the carriage 2 reciprocating mechanism (not shown) is turned on and driven rotation of the atomizer 1. Particles of the material being sprayed fly from the atomizer 1 in the direction of the axis of the product 13, fall on the conical surfaces of elements b and 7 of screen 4, are reflected from them and fall on the flat surfaces of the upper bases of elements 7, where Precipitational forces are thrown away from a strictly perpendicularly sprayed surface, forming a coating.

Moving synchronously the nebulizer 1 and the screen 4 along the axis of the product 13, consistently apply a coating on the entire inner surface of the product 13. At the same time, the flow of hot gases (plasma, compressed air or flame) through the gaps between elements 6 and 7 of the screen 4 and the internal cavities of the elements 7 exits from the opposite side of the product. By heating the surfaces of the elements 6 and 7 of the screen 4, crystallisation and fixation of the sprayed particles on them is prevented. In this case, the heating temperature of the elements 6 and 7 of the screen 4 must be higher than the melting point of the sprayed material. In this case, there is no sticking.

particles on the elements 6 and 7 of the screen 4, does not require time for their cleaning and the performance of the process increases.

Thus, in comparison with the known device, the proposed device

provides a higher quality of the applied coating on the internal surfaces and, by reducing the time spent on cleaning the screen, improves the performance of the spraying process.

Claims (1)

Claims The device for coating on the inner surfaces of products contains a spray gun, a mounting device and a rotating screen made as a set of elements mounted on one axis with displacement, the first of which is conical along the sprayed coating, and the rest are made The form of truncated cones with internal through cavities, characterized in that, in order to improve the quality of the coating and the performance of the work, each element of the screen is provided with a heating device, and the diameter of the lower base of the previous element of the screen is smaller than the diameter of the upper base of the subsequent element; the element is selected from the ratio / arctgC) where dnc. dnp - diameters of the upper bases of the subsequent and previous conical elements, mm; a is the distance between them. mm  ///// Ж / ШШШШШ ////// shsh ////// Fig Figi Yu Fi.Z