CN112475803B - Preparation method of large-diameter circular metal splicing block - Google Patents

Abstract

The invention relates to the field of machining, in particular to a preparation method of a large-diameter circular metal splicing block. The processing method can save raw material cost and processing time by carrying out pretreatment on the size of the part, then processing the whole next ring material, separating each splicing block by adopting linear cutting after the processing is finished, and meeting the design precision requirement after the splicing is closed again.

Description

Preparation method of large-diameter circular metal splicing block

Technical Field

The invention relates to the field of machining, in particular to a preparation method of a large-diameter circular metal splicing block.

Background

Some circular ring-shaped parts with large diameters are often encountered in sheet metal molds and precision casting molds, and the parts are usually designed to be formed by splicing a plurality of splicing blocks for demolding, and the splicing blocks are required to be tightly attached or have a gap not larger than 0.03 mm.

As shown in the attached figure 1 of the specification, the whole circular ring piece is composed of 8 splicing blocks, the central included angle corresponding to each splicing block is 45 degrees, and the splicing blocks move radially along the key groove direction during die opening and die closing.

The traditional processing methods are of two types: one method is that each splicing block is independently discharged and processed and then combined into a whole ring, and the processing method has the problems that because each splicing block has processing errors, the profiles of the joints of each splicing block are often inconsistent during assembly, and the close fit of the joint surfaces needs a large workload and the quality is not easy to ensure; the second method is that each split is blanked separately, the joint face is processed first, then the whole ring is processed by using special fixture, although the processing precision is improved, some special fixtures are needed, the cost is higher, and the processing period is longer.

Disclosure of Invention

The invention provides a preparation method of a large-diameter circular metal splicing block, and aims to save raw materials, improve the processing efficiency, and save the processing cost and the production period.

The technical scheme of the invention is as follows:

a preparation method of a large-diameter circular ring-shaped metal splicing block comprises the following steps:

(1) determining linear cutting equipment for cutting the split block in future, and determining a cutting gap by using the cutting block;

(2) calculating the radial movement distance required by closing before cutting the splicing block to after cutting the splicing block according to the central included angle corresponding to the splicing block in the drawing and the movement direction of the splicing block;

(3) adjusting the drawing size, keeping the height direction size H and the normal direction size B unchanged, and increasing the radial size of the ring by a corresponding distance, namely phi _{After adjustment} ＝φ _{Before adjustment} +2S, as shown in FIG. 3 of the specification, the sizes of phi 1 to phi 7 are all increased by 2S after adjustment, for example, phi 1 _{After adjustment} ＝φ1 _{Before adjustment} +2S, the other sizes H1-H6, B1-B2 and the central included angle alpha corresponding to each tile are kept unchanged;

(4) checking whether the profile degree meets the design precision requirement;

(5) processing according to the adjusted drawing size, and integrally processing by using an integral ring during blanking;

(6) after the processing is finished, each splicing block is cut by linear cutting, and finally the joint surface is polished by a bench worker.

In the above method for manufacturing a large-diameter circular ring-shaped metal segment, the formula of the radial movement distance of the segment in the step (2) is calculated as S ═ a/2)/sin (α/2), as shown in fig. 2 in the specification, a is the cutting gap.

In the preparation method of the large-diameter circular metal splicing block, in the step (6), the sequencing condition of each splicing block before cutting needs to be accurately marked when each splicing block is cut, and the splicing blocks are assembled according to the sequence when a mould is assembled.

The beneficial effects of the invention are as follows:

(1) the processing method is simple to operate, and can completely meet the design requirements for processing the splicing blocks with large radius and short circular arcs;

(2) the processing efficiency can be improved by 3-5 times, the processing cost and the material cost can be reduced by 20-30%, and the method has great advantages compared with the existing processing method.

Drawings

FIG. 1 is a schematic diagram of a prior art circular ring segment assembly;

FIG. 2 is a schematic view of calculating a radial movement distance;

FIG. 3 is a schematic drawing of part dimensions;

FIG. 4 is a schematic diagram of an embodiment of a circular ring segment assembly;

FIG. 5 is a schematic diagram illustrating the calculation of the radial movement distance according to an embodiment of the present invention;

FIG. 6 is a schematic diagram of the adjusted ring segment size;

FIG. 7 is a schematic view of a circle arc being adjusted to fall within the tolerance band:

FIG. 8 is a schematic diagram of the adjusted arc not falling within the tolerance band.

Wherein: 1-splicing blocks; 2-key groove.

Detailed Description

The embodiment will be described by taking the circular segment shaped segment shown in fig. 4 as an example.

As shown in fig. 4, the overall dimension of the part is phi 800 x phi 580 x 150, the whole ring is composed of 8 segments, the central included angle corresponding to each segment is 45 degrees, the moving direction of each segment in use is along the key groove direction, the single piece design precision requirement is 0.1mm, and the precision after assembly is 0.2 mm.

The preparation method specifically comprises the following steps:

(1) determining equipment for cutting the string into the splits and determining a cutting gap by a test block:

according to the size of this part, it was determined that the segment was cut on a medium-speed wire cutting apparatus, a 20mm long test piece was cut into two pieces from the middle, the wire cut surface was polished to a roughness of ra0.8, and then the total length of the two pieces was measured to become 19.74mm, thereby determining a cutting gap of 0.26 mm.

(2) Calculating the radial movement distance required by close fit before cutting the splicing block to the cutting back of the splicing block according to the central included angle corresponding to the splicing block in the drawing and the movement direction of the splicing block:

as shown in fig. 5, when the cut gap is 0.26mm, the distance required for each cut tile to move inward along the key way direction if close together is 0.13/sin (22.5) — 0.34 mm.

(3) And (3) adjusting the drawing size, keeping the axial size and the normal size unchanged, increasing the radial size of the ring by a corresponding distance, wherein the adjusted drawing size is shown in FIG. 6, and the external dimension of the part is phi 800.68 multiplied by phi 580.68 multiplied by 150.

(4) Checking whether the profile tolerance meets the design precision requirement:

as the radius of the splicing block is smaller and the profile deviation is larger for the same central included angle, the checking is only carried out on the circular arc with the minimum diameter, the circular arc with the minimum diameter in figure 4 is phi 580, and if the design precision is phi 580 ₀ ^+0.1 The tolerance zone is on concentric circles of R290-R290.05, phi 580 is adjusted to be phi 580.68, and drawing shows that within the arc range of 45 degrees, the adjusted arc phi 580.68 is completely contained in phi 580 after being moved by 0.34 ₀ ^+0.1 In the tolerance band of (a), when it is determined that the design requirements are met, this method may be used; if the design accuracy is phi 580 ₀ ^+0.05 The tolerance zone is on the concentric circles of R290-R290.025, and the drawing shows that the adjusted circular arc phi 580.68 cannot be completely contained in phi 580 within the circular arc range of 45 degrees after being moved by 0.34 in the circular arc range of 45 degrees as shown in figure 8 ₀ ^+0.05 When it is determined that the design requirements are not met, this method cannot be used.

(5) And (5) processing according to the adjusted drawing size, and integrally processing by using an integral ring during blanking.

(6) After the processing is finished, each splicing block is cut by linear cutting, the sequencing condition of each splicing block before cutting needs to be accurately marked during cutting, the die is assembled in the sequence strictly during assembly, and the cutting is finished by one-time feed, so that the joint surfaces of the adjacent splicing blocks are cut by the same cutter, the trimming and grinding are basically not needed during assembly, and only the simple polishing is needed.

Claims (2)

1. A preparation method of a large-diameter circular ring-shaped metal splicing block is characterized by comprising the following steps:

(1) determining linear cutting equipment for cutting the split block in future, and determining a cutting gap A by using the cutting block;

(2) calculating the radial moving distance S required by the closing and the sealing from the cutting of the splicing blocks to the cutting of the splicing blocks according to the central included angle corresponding to the splicing blocks in the drawing and the movement direction of the splicing blocks, wherein S is (A/2)/sin (alpha/2), and alpha is the central included angle corresponding to each splicing block;

(3) the drawing size is adjusted, the height direction size H and the normal direction size B are not changed, and the radial size of the circular ring is increased by a corresponding distance, namely phi _{After adjustment} ＝φ _{Before adjustment} + 2S; (4) checking whether the profile tolerance meets the design precision requirement;

(5) processing according to the adjusted drawing size, and integrally processing by using an integral ring during blanking;

(6) after the processing is finished, each splicing block is cut by linear cutting, and finally the joint surface is polished by a bench worker.

2. The method according to claim 1, wherein in step (6), the order of the segments before cutting is marked accurately and the segments are assembled in the order during the assembly of the mold.

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