RU2443531C2 - Method of reconditioning tillage equipment working tools with complex shape - Google Patents

Abstract

FIELD: process engineering.

SUBSTANCE: invention may be used in reconditioning tillage equipment working tool surfaces with complex shape. Worn-out area is prefilled by electrodes made from wear resistant material to perform closing by fusion in one pass by electric arc manual or semiautomatic method to ensure maximum possible tracing of working surface.

EFFECT: eliminating wear with residual thickness of working element of smaller than 2 mm, recovery of part with through rubbing.

2 dwg

Description

The invention relates to the field of welding production and repair of machines, in particular to the restoration of parts of tillage machines operating in conditions of abrasive wear and having wear of complex spatial shapes.

A known method of wide-layer surfacing under a flux layer of flat surfaces of products that have lost their geometric dimensions, which uses a lying plate electrode with an additional additive [1].

The method cannot be applicable when surfacing surfaces with a complex spatial geometry of wear (for example, when this wear is a luvoid form in the horizontal plane and a semi-ellipsoid in a vertical section), due to the difficulties of forming charge materials for subsequent surfacing. In addition, when surfacing curved surfaces there is no possibility of obtaining the required thickness of the deposited material in one cycle of the surfacing operation.

The closest technical solution, selected as a prototype, is a method of restoring and hardening a plow share with lucid wear, which involves surfacing of two layers of metal of different hardness, when the first provides ductility, and the second abrasive wear resistance of the surface in contact with the soil [2].

The disadvantages of the prototype are the need for repeated passes to eliminate wear and ensure the wear resistance of the working part of the product; high probability of warpage; difficulties of the technological plan in eliminating wear with a residual thickness of the working element of less than 2 mm; difficulties in restoring parts with through wiping; low productivity.

The technical result of the invention is the renewal of the resource of the part lost due to the appearance of wear of a complex spatial shape by melting the defective area by electric arc welding using electrode material previously laid in the worn area, which is characterized by increased wear resistance and meets the operational requirements for the working surface.

The specified technical result of the invention is achieved by melting a worn-out region having a complex spatial geometry by an electric arc manual or semi-automatic method according to a previously laid electrode material in this volume. The deposited material should have a volume of metal that compensates for losses from wear.

The claimed method is carried out due to the following factors. Electrodes for manual welding or surfacing are laid in the wear area with its maximum filling. The number, diameter and length of the electrodes are determined by the spatial geometry of wear. Subsequent exposure to the area prepared for restoration by the welding arc allows it to be melted in one pass and in the presence of through wipes (In case of significant values of through holes, it is recommended to use graphite linings). To ensure the wear-resistant properties of the deposited metal, it is necessary to introduce electrodes into the stacked electrode material, which provide high hardness of the deposited layer. Moreover, electrode materials providing high wear resistance should be located on the surface.

A comparative analysis of the claimed solution with the prototype shows that the claimed method differs from the known one in that the restoration is provided by surfacing in one pass; it is possible to melt wear areas with through wiping and a residual thickness of less than 2 mm, as well as the use of electrodes that provide high surface wear resistance as part of the electrode laying material in the absence of warpage of the product. Thus, the proposed method meets the criterion of "novelty."

Known technical solutions involve melting the worn area with a lying electrode, or multi-pass melting by manual arc welding, applying two layers or more differing in their mechanical properties, which is absent in the proposed method and allows us to conclude that it meets the criterion of "significant differences".

In Fig. 1, a portion of the working body with lateral wear is provided, where 1 is the area of lateral wear; 2 - lucid form of wear in the horizontal plane; 3 - a form of wear in the form of a semi-ellipse in a vertical plane; 4 - electrodes laid in the worn part; 5 - surfacing electrode (section AA is shown on a 1: 1 scale).

Figure 2 presents the restored part, where 6 is a fused section.

The implementation of this method is illustrated by the example of restoring a worn ploughshare of a plow 1 of domestic production of P-702 brand. Before melting, 2, 3 electrodes 4 are laid in the worn area. The diameter of the electrodes, their length and quantity are determined by the spatial configuration of the wear region. Melting is carried out by manual arc welding with an electrode 5 of the UONI series with a diameter of 5 mm with a welding current strength of J = 180 ... 200 A in one pass. As electrodes of laying any electrodes with low-carbon rods are applicable. To increase the wear resistance of the contact surface, electrodes were used for wear-resistant surfacing of T-590 alternating with low-carbon ones. The restored area 6 should maximally copy the surface of the work item.

Information sources

1. Patent RU 2179913 C1. The method of wide-layer surfacing [text] / Putilin V.G., Nikolaenko M.R., Abrashin A.V., Koryazhkin V.V., publ. 02/27/2002.

2. Patent RU 2370351 C1, A method for restoring and hardening plow shares to eliminate lunar wear by two-layer surfacing [text] / Mikhalchenkov A.M., Tyureva AA, Kozarez IV, Komogortsev VF, publ. 10.20.2009, BI No. 29.

Claims (1)

A method of restoring working elements of tillage equipment having a complex spatial geometry of wear, characterized in that the worn area is preliminarily filled with electrodes from a wear-resistant material and melted in one pass by an electric arc manual or semi-automatic method to ensure maximum copying of the surface of the working element.

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