SU1404309A1 - Method of abrasive-jet machining of parts - Google Patents

Abstract

The invention relates to inkjet waterjet processing of materials, and in particular to methods of cleaning surfaces of parts having a cellular structure of a rectangular shape. The aim of the invention is to improve the processing quality of the side faces of the rectangular cells on the surface of the part. For this, fan-shaped jets 11-14 of the working agent are directed to the surface of the part from the slotted nozzles. At the same time, each of the four nozzles are oriented relative to the cells on the treated surface as follows: first, nozzles 7, 8 and 9, 10 are deflected in pairs from the normal to the surface in opposite directions, and then rotate them along their longitudinal axes in opposite directions, fixing the position of the nozzles when the planes of their jets 11–14 coincide with the diagonals of the rectangular cells; on the surface of the part 1. Then one of the pairs of nozzles, for example 9 and 10, is turned relative to the other pair of nozzles. horizontal plane at an angle of 180 °. 2 hp f-ly, 4 ill.

Description

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The invention relates to the field of sandblasting materials, and in particular to methods for stripping off burrs and rounding the edges of surfaces of parts having rectangular cells.

The aim of the invention is to improve the processing quality of the side edges of the rectangular cells on the surface of the part.

 Figure 1 is a diagram of the processing of a part with rectangular cells; figure 2 - view B in Fig, 1; in FIGURE 3, section A-A in FIG. figure 4 is a characteristic node of the intersection of the edges of the i cell of the treated surface.

The workpiece 1 with rectangular cells 2, which contains intersection nodes of faces 3 with 4 longitudinal and 5 transverse edges located on the surface of the part, as well as edges 6, located in the depth of the part, in particular from the slit Bbix nozzles 7-10, installed with the possibility of movement, are simultaneously supplied with flat fan-shaped (with divergence angle /) hydroabrasive jets 11-14.

When machining, the nozzles 7–10 orient the surface of the part normally and turn around their axes until the traces of flat hydro-abrasive jets 11–14 coincide with the direction of the diagonals of the cells, and the jets are oriented in pairs: two relative. but one diagonal and two relative to another. After that, each of the jets that make up a pair is inclined relative to their common normal to the surface to be treated (the turning axis is the cell diagonal) until each of the jets reaches a meeting with the surface being treated, equal to ft (FIG. 3).

Then, maintaining the resulting orientation, the slit nozzles 7-10 are moved parallel to the treated surface so that the processing strips (H) of the jets 11-14 coincide.

Machining the part 1: is performed by moving it under the jets 11-14 in the direction coinciding with the direction of the length of the faces of the cells 2. After each pass of the part 1 under the indicated streams it is shifted across the direction of movement by an amount not exceeding half the width

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processing bands (H). Instead of moving part 1 by the same amount, slit nozzles 7-10 can be moved while maintaining their orientation. Alternate longitudinal movements of the part and lateral displacements of the jet-forming devices are carried out until the entire surface of the part has been machined, for example, the burrs have been removed and the edges of the ribs are rounded.

When processing by the proposed method, at all points of the surface of the cells 2, including the fins 6, which are perpendicular to the surface to be treated, there is a multiple force effect of abrasive particles. This effect is produced at a constant meeting angle p, but in a variable direction (nozzles 7 and 9 work in one direction, and 8 and 10 in the other).

The width of the hydroabrasive jet created by each slit nozzle 7-10. is determined by the angle of divergence o (jets 11-14, which depends on the geometrical dimensions of the nozzle and the mode of processing parameters.

The angle / i of meeting the jets 11-14 with the surface of the workpiece I is selected depending on the physical properties of the material of the part 1 and the required surface quality from a range of 30-60 relative to the surface of the part, provided that the value of the slant range, i.e. the shortest distance from the slice of the slotted nozzle to the place of processing on the part. For soft alloys such as aluminum or copper, the angle |} is 30-4. In this case, high productivity and cleanliness are achieved. A meeting angle of 40-60 ° is recommended when machining stainless steel, titanium, cast iron, ceramics and metal ceramics parts that have recesses of a complex configuration on their surface, including edges, are perpendicular to the surface to be treated. These materials, which have increased viscosity and hardness during processing with an encounter angle of 40 to 60 °, allow for maximum performance and an acceptable quality during processing. During processing, the productivity is reduced, and the deep parts of the vertical edges

the ribs may appear in the shade, i.e. not treated, although the roughness of the surfaces after treatment is noticeably improved. An increase in the meeting angle of more than 60 is characterized by an increase in the roughness of the parts, there is a noticeable difference in the roughness of the horizontal and vertical surfaces of the cells, i.e. grooves on the surface of the parts, and increasing the caricature of the machined surface. In this case, the vertical size of the cells also begins to affect, the vertical edges located in depth are treated worse than those that are located closer to the surface.

Example. A detail was machined with the cellular surface of AMg-6 aluminum alloy, with a cell size of 150x150 mm. The treatment was carried out with four slit nozzles operating in pulsed waterjet mode. The flow rate of the energy carrier fluid through one nozzle is 0.5 l / s, the supply pressure is 15 MPa, and the volume flow rate of the supply is abrasive. pulp 0.5 l / s, pressure about 0.1 MPa, volume concentration of abrasive 30%, abrasive - electrocorundum. The angle of inclination of the planes of the jet to the plane of the part 40.

The cells on the parts have a depth of 20 mm and are obtained by milling. In the course of processing, it was necessary to remove the burrs formed after machining, to round off the edges of the edges of the cells with a radius of at least 0.4 mm and to remove the marks from the cutter in the corner of the broken cells.

After a single movement of the part under four nozzles oriented according to the proposed method, the cells were processed at a speed of 0.35 m / s in accordance with the requirements, and

Burrs completely removed on the longitudinal and transverse edges, as well as on the ribs located perpendicular to the surface of the part, the sharp edges of the ribs are rounded with a radius of 5 mm, and there are no traces from the cutter in the recesses of the cells. The surfaces of the part after processing have a uniform silver-matte color without noticeable visually traces of mechanical processing.

Thus, the proposed method makes it possible to increase the efficiency of surface treatment of parts that have a cellular structure of a rectangular shape.

Claims (3)

1. The method of abrasive blasting processing of parts, in which the surface to be machined from at least two slit nozzles, is symmetrically rejected. fanned jets of the abrasive slurry are opposite to the normal to the surface, and the parts are given a reciprocating movement relative to each other. but nozzles, characterized in that, in order to improve the quality of the processing of the lateral faces of rectangular cells, the slit nozzles rotate relative to their longitudinal axes in mutually opposite directions and direct fan-shaped jets in planes parallel to the diagonal of rectangular cells. 2. Method according to Claim 1, which is different from the fact that the treatment is carried out with an additional pair of slits, while it is rotated relative to the main pair of nozzles in the horizontal plane through an angle of 180 °. 3. The method according to PP.1 and 2, characterized in that the slotted nozzles are deflected from the normal to the treated surface by an angle of 30-60. Buds Phys .2 Fig.Z Fiz,