Determination and application of the size range of

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With the rapid development of information technology, many forging enterprises began to use CAPP system to replace the traditional manual programming process, which greatly improved the production efficiency. At present, the forging CAPP system is generally developed according to the order of specific enterprises, and its versatility is not strong. In order to improve the versatility of the system, it is necessary to establish a scientific forging process decision-making model and develop the corresponding forging process decision-making system. This paper takes the common rotary forgings such as disk, ring, sleeve, column and shaft in forging production as an example. On the basis of the national standard of free forging, the actual production situation of forging enterprises in machinery, metallurgy and other industries is comprehensively analyzed, and the size range of disk, ring and sleeve forgings is reasonably divided. On this basis, the decision-making model of forging deformation steps is obtained. The practice shows that the application effect is good

2 existing problems in the size division of disk, ring and sleeve forgings

in the series forgings of free forging, disc (including perforated disc and solid disc), ring, sleeve, cylinder, round light axis and other zero Anyang are important base parts in the province, which are relatively similar in shape. If the hole diameter of solid disc, cylinder and round optical axis is considered to be zero, the overall dimension parameters of these types of forgings are also the same, that is, outer diameter D, inner diameter D, height H. the forging model diagram is shown in Figure 1. The division of specific types is often based on the internal/external diameter ratio d/d and the height/diameter ratio h/d. The division range of disk, ring, sleeve and other forgings according to CAD's current national forging standards is shown in Table 1 ◆ the test object automatically returns to normal temperature at the end of the experiment to avoid frost and condensation protection mechanism. Draw the data in Table 1 into a regional line diagram, as shown in Figure 2

compared with the regional line map of disk ring sleeve forgings in the national standard, it is not difficult to find that according to this range division method, there are two main problems: first, the forging types have staggered overlapping areas, that is, there are two or more forging types at the same position in the regional line map; Second, there is a large blank area, that is, in some positions of the regional line map, the forging type is empty, but in actual production, there are forging types

although the shape of disc ring sleeve forgings is similar, there are great differences in forging technology. The possibility of cracks caused by sticking face bricks or coating on its surface will also increase the possibility of forging CAPP system. When making forging process decision, only by first determining the type of forging, can the process decision be automatically completed. In this way, if the parameters fall in the staggered overlapping area and blank area in the above forging area line diagram, there will be ambiguity of forging type or vacancy of forging type, and CAPP system cannot realize the automatic decision-making of forging process of the forging

3 adjustment of forging division range and establishment of decision-making model

in order to realize the automatic decision-making of the process of disc ring sleeve forgings under the forging CAPP system, we must scientifically subdivide the overlapping areas and blind areas in the regional line diagram of disc ring sleeve forgings according to the actual situation of the forging processing process and based on h/d, d/d and other parameters, so as to make the forging types in each area clear. On the basis of summarizing the experience of developing forging CAPP system and according to the actual production situation of forging enterprises, the h/d and d/d range of disc ring sleeve forgings are adjusted. The adjusted range is shown in Table 2. According to the parameter range in Table 2, draw the adjusted regional line diagram of disc ring sleeve forgings, as shown in Figure 3

The forging CAPP system must first determine the forging type when making the process decision of disk, ring and sleeve forgings. Now the commonly used method is to determine the forging type by the operator before inputting the parameters, and then directly call the process decision system of this kind of forgings. Considering the convenience of system operation and the reduction of operator workload, the unified input interface is adopted for the description and input of disk, ring and sleeve parts information during system development, as shown in Figure 4. When the part parameter information is input, the system calls the discrimination program of disk ring type to automatically complete the type determination of forgings, and directly calls the corresponding decision-making module to complete the forging process decision according to the type of forgings. The decision-making flow chart is shown in Figure 5

considering the similar shape of disc ring sleeve forgings, the system defines a user-defined structure for the contour data of disc ring sleeve forgings. The structure has a total of 4 attribute bits, which represent the forging type, inner diameter, outer diameter and height dimension parameter information respectively

among them, solid disc, column, shaft and other forgings can be considered as a special case where the XD attribute value of disc ring sleeve forgings is zero

according to the adjusted disc ring sleeve type classification table, the following knowledge reasoning for the type discrimination decision of disc ring sleeve forgings can be obtained:

when the disc ring sleeve forgings are free forged, they are affected by the forging process, and the forging type will jump correspondingly when certain boundary constraints of the forging process are met. For example, according to the technical parameters of the ruler tension machine: the initial judgment type of inch is the perforated disc (ring sleeve) forging. In the following cases, the central hole will not be forged, and then the forging type will be changed to the solid disc (column) and other types

(1) for forgings on the guard hammer, when the hole is 3*pht XD or pht HH≤3*, ≤O. 5*PHT. DD, the hole is not allowed to be forged

(2) for sleeve forgings, when

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