RU2533515C1 - Method of induction surfacing - Google Patents

Abstract

FIELD: process engineering.

SUBSTANCE: invention relates to machine building and may be used for increasing wear resistance of outer cylindrical surfaces. Proposed method comprises placing the article horizontally, placing two plates in symmetry relative to vertical, plates being made of graphite and spaced there between being equal to width of ply being built-up and height exceeding ply height. Portion of facing material is applied between the plates. Facing material and article surface are processed unless their joint fusion. After processing by inductor and a melt hardening the article is turned through surfacing pitch equal to the sum of applied ply width and plate depth. Then, first plate as seen along turning direction is moved to the place occupied by the second plate. Surfacing material is applied between the plates and processed by inductor. After melt hardening, the article is again turned through the same surfacing pitch to reiterate surfacing cycles unless grooves are formed over its entire surface. Now the built-up surface is turned to required diameter.

EFFECT: optimised process, higher tribotechnical properties.

3 dwg

Description

The invention relates to mechanical engineering and can be used to increase the wear resistance of the outer cylindrical surfaces of the products.

There is a method of induction surfacing, which consists in the fact that a layer of deposited material (for example, in the form of a paste or a mixture) is deposited on the surface to be welded and subjected to joint heating by high-frequency currents using an inductor until the surface of the product is melted and the deposited material is melted; after the inductor is turned off and the product and the deposited material are cooled, a deposited layer forms on the product (see, for example, Anikin N.A., Drobyshevskaya N.I., Dudinov V.A. et al. Handbook for the inventor and rationalizer. 3rd ed. And additional Moscow-Sverdlovsk, Mashgiz, 1962. 792 pp., Ill., P. 543).

The disadvantage of this method is that it is not applicable for surfacing of the outer cylindrical surfaces, since the deposited material is not held on these surfaces due to their curvature.

As a prototype, the method of induction surfacing according to the USSR AS No. 1794610, class. B23K 13/01, publ. 02/15/1993, bull. No. 6. Its essence is that the correct polyhedron is preliminarily made from a cylindrical part, the deposited material is applied to each of the faces, sequentially setting them horizontally, the deposited material is treated with an inductor, after cooling the melt, horizontally intersecting the sections of intersection of the faces is repeated, repeating the same operations , the process is repeated until a layer of deposited material of the required thickness is obtained, after which the part is processed to a predetermined diameter a.

The disadvantage of the prototype is that in this method, the part before surfacing must be trimmed, which is not technologically advanced, leads to an overuse of the material of the part and requires additional time costs; a separate deposited layer is obtained with a small thickness, due to the fact that the melt tends to spread and drain from its faces, this requires the repetition of a large number of separate surfacing operations, which lengthens the deposition process, especially since it is necessary to wait for the melt to solidify after each individual deposition; while the total deposited layer is heterogeneous, which affects its performance; in addition, the total deposited layer is continuous, and if it is necessary to make oil grooves in the deposited surface (to improve the tribological characteristics of the product surface), additional operations are required to cut them in this surface, which is non-technological, requires additional time and is difficult, t. to. the deposited surface has increased hardness.

The invention solves the problem of optimizing the surfacing process and improving the tribological characteristics of the deposited surface.

This is achieved by the fact that the product with a built-in outer cylindrical surface is installed horizontally; on the upper part of the surface, along it, symmetrically with respect to the vertical and radially relative to the product, a pair of plates made of a heat-resistant non-metallic material, for example graphite, with a distance between them equal to the specified width of the one-time deposited layer and a height greater than the height of this layer; a portion of the deposited material is applied between the plates and treated with an inductor; after solidification of the melt, the product is cranked up by the step of surfacing equal to the sum of the width of the deposited layer and the thickness of the plate; rearrange the first plate in the direction of rotation of the product to the place that the second plate originally occupied; the deposited material is again applied between the plates and treated with an inductor; after solidification of the melt, the product is again rotated by the same step of surfacing; rearrange the first plate in the course of turning the product to the place that the second plate occupied before turning, and repeat the surfacing cycles until the surface of the product is fused over its entire circumference; after the end of the welding process, the product is grinded to the required diameter.

The invention is illustrated by drawings, which depict a product with a weld surface (end view) in various phases of the welding process - figure 1, 2, 3. The drawing shows: product 1; surfaced surface 2; plates 3 and 4 of thickness m; deposited material 5 (layer of thickness h in its middle part); inductor 6; axis of rotation 7 of the product; direction of rotation from the product; angle 2α of the arc of the circumference of the product, occupied by a one-time deposited layer; the angle β of the arc of the circumference of the product, occupied by a one-time deposited layer and one plate; the gap 9 is between the deposited layer 8 of the surface 2.

Implemented the proposed method as follows. Product 1 with a built-in outer cylindrical surface 2 is installed horizontally; a pair of plates 3 and 4 made of a heat-resistant non-metallic material, for example graphite, with a distance between them equal to the width of a one-time deposited layer (the width is determined based on the required thickness, is installed on the upper part of the surface, along it, symmetrically with respect to the vertical and radially relative to the product, the deposited layer, the diameter of the product and the curvature of the deposited surface; the number of one-time deposited layers (n) is:

, $$n=\frac{C}{l+m}$$

,

where C is the circumference of the product;

l is the length of the arc of a circle (C) occupied on the circle by a one-time deposited layer;

m is the width of the plate),

and higher than the height of the deposited layer; install disk-shaped end plates on the ends of the product in contact with the ends of the platinum and forming together with them a surfacing bath (not shown); a portion of the deposited material 5 is applied between the plates and treated with an inductor; after the solidification of the melt, the product is rotated by a step of surfacing equal to the sum of the width of the deposited layer and the thickness of the plate by an angle β; rearrange the first plate in the direction of rotation of the product to the place freed by the second plate; deposited between the plates deposited material and process it with an inductor; after the solidification of the melt, the product is again rotated to the same step of surfacing; rearrange the first plate during the rotation of the product to the place freed by turning the product by the second plate, and repeat the surfacing cycles until the surface of the product is fused over its entire circumference. Upon completion of the surfacing of the entire surface, the weld surface is grinded to the required diameter. The gaps obtained during surfacing (9) between the deposited sections (8) of the surface, formed by the plates present during surfacing, are used as lubrication grooves during operation of the product. By varying the values of l, m, as well as the number of one-time deposited layers (n), the surface of the product with the necessary tribotechnical characteristics is obtained.

Compared with the prototype, the proposed method of induction surfacing allows for surfacing more efficiently, because the surface is surfaced once at the full required height of the deposited layer to the entire required thickness, which helps to achieve uniformity of the deposited layer and increase its operational characteristics; this method does not require cost overrun of the material of the product going to shear to obtain weldable faces; operation to cut the product is excluded; labor productivity increases since a one-time deposition of a layer of the required thickness is performed, the waiting time for the solidification of the deposited layers is reduced; due to the formation of lubricating grooves on the surface, the tribotechnical characteristics of the deposited layer increase, which contributes to its wear resistance and durability.

Claims (1)

The method of induction surfacing of the outer cylindrical surfaces of products, including installing the product horizontally, applying to the part of the surface of the product along its entire length a portion of the deposited material, treating the deposited material with the inductor and the surface of the product until they are melted together, turning the product around its longitudinal axis of symmetry after the melt has solidified deposition step, repetition of similar operations to obtain a deposited layer around the entire circumference of the product and subsequent wrapping pumping the product with the deposited surface to the required diameter, characterized in that before applying the deposited material to a part of the deposited surface of the product, a pair of plates made of graphite are installed symmetrically relative to the vertical of the product, the distance between which is equal to the specified width of the deposited layer, and the height is greater than the height of the said layer , while a portion of the deposited material is applied between the plates and after processing with an inductor and solidification of the melt, the product is turned a step Avki, equal to the sum of the width of the deposited layer and the thickness of the plate, then they rearrange the first plate in the direction of rotation of the product to the place that was originally occupied by the second plate, a portion of the deposited material is applied between the plates and treated with an inductor, and after the melt has solidified, the product is again rotated by the same step deposition and repeat the deposition cycles until deposition of the surface of the product along its entire circumference with the formation of grooves.

Images