The choice of rational forms of organization of the...

Choosing rational forms of organization of the production process

Flow-group process organization form

Q. A. Petrov [17] proposes to use the provisions of the theory of pattern recognition with the help of a potential function when solving this problem. If we introduce the following concepts and notations: K XiYi. - a measure of proximity between two groups of parts (X ;, Xj ) ; R XiXj. - the measure of the distance between X t andX ) by groups of parts for a number of characteristics P = 1, ..., k, then to determine the measure of proximity you can use a potential function of the form

where λ is the coefficient of proportionality. The function R XiXj has the form

where ( x k, i -x k, j) is the calculated difference characterizing the closeness (or distance) between X i and X j groups of parts in the k -th attribute.

In this case, the values ​​of X i and X j for the set of P -th attributes are expressed by numeric codes having the same structure (bit depth) and strict orientation (ascending or descending proportion of characteristics).

When forming the sub-specialized shops, sections and group flow lines from the set of formed parts groups, select (fix) the group P 3 and P 4 that is the most complex > X i. By means of a sequential comparison with the base group, the values ​​of R XiXj for each group of the subset accepted for synthesis are calculated from these characteristics. Then the obtained values ​​are ranked in the order of their decrease. The formed first section of the ornated subset of the detail groups will include d y groups according to the condition

where d y - the number of parts groups assigned to the y-th site; C y - the average constant of the equality of parts; D is the number of parts in the population.

Flexible form of process organization

When allocating group flow lines (GPL) as part of a boundary condition, the not accepted normative value of the proximity measure coefficient is used: for the details of the machine-building profile ε = 0,85 , a purely instrument-making ε = 0.90. The selection of the groups of parts for the formed GPL is completed under the condition min

In order to increase the level of mechanization and automation of serial, small-scale and single productions in recent years, the development and implementation of CNC machine tools, machining centers and robotics at the country's enterprises have been stepped up. Widely deployed work on the creation of machining workshops and sites based on uninhabited or low-technology due to the use in the management of technical means and production of microprocessor equipment and computers. At present, such complexes are called flexible production systems (GPS).

Flexible automated (automatic) production is created to ensure a rapid restructuring of production with a dynamically increasing variety of objects of new technology; the solution of social problems, in particular the problem of increasing the intellectual content of labor - the release of a person from routine and monotonous operations, from working in harmful conditions.

Criteria to achieve these goals is a sharp increase in labor productivity in the manufacture of single and small-scale production in 3-5 times, serial - in 1,5-2,5 times, a significant reduction in the cycles of creation, preparation, development and production of new products or their parts.

Three to nine flexible automated lines (GAL) are included in the flexible automated section (GAC), which corresponds to the total number of machine modules (SM) to 27 pcs. The composition of the GAL includes A -5 GAC with a total number of CM from 108 to 135.

When designing GAL for small-scale and single-productions, their structuring is performed on the basis of the methods used in the formation of group production lines (GPL). However, these methods and calculations are supplemented taking into account the features due to the new structural properties of the GAP.

1. Higher performance GAL. On the basis of the tasks set for the GAL conditions for increasing labor productivity, the required reduction in the labor intensity of the parts is determined from the known dependence. b = 100 a /(100 + a ). Then the calculated coefficient of toughening of the current norms ( K un) to bring them to the identical conditions of the GAP technology will be K un = 1 - b/100. In this regard, the approximate number of basic machine-tool modules Scm) in the proposed version of the GAP will be defined as

Example

A GAL with labor productivity is twice as high on a GPL basis for K gm = 18. It is necessary to determine SCM GAL.

1. Determine: the required reduction in labor input - and = = 100 - 200/(100 + 200) = 67; coefficient of toughening of norms - Kuhn = 1 - 67/100 = 0,33; number of machine modules - S cm = 0,33-18 = 6.

2. GAL should handle any details regardless of the volume of their release. In this case, there is no need to take into account in the number of signs Р ш the average value of the index of relative labor for parts groups K gm (sign Р 5).

3. GAL is formed taking into account additional features: accuracy of processing, surface cleanliness, etc. This is taken into account when calculating the distance measures R XiXj in the vicinity of K XiXj. In addition, in order to improve the accuracy of the results of a comparative assessment of the structural and technological community of groups assigned to the GAL details, the coefficient of specific significance (γ) of each characteristic in the formula for calculating the index R XiXj under the root sign in front of the difference squares the aggregate characteristic of the properties of the generated GAL ( Σγ = 1). Values ​​

γ, is determined by the method of priority ranking of characteristics by factors and objects stated in the special literature.

Process Organization Routing Form

Based on the same classification materials (see Table 5.1) and the methods that were used earlier for the formation of flow-group sites, it is possible to form production divisions with a route form of organizing the production process, i.e. such a form in which each set of parts is assigned a set of parts, formed on the program and manufactured according to one typical technological route.

When forming a CSP with a route form of production organization (i.e., a route section), four design and technological characteristics ( P 1, P 2 , P 3, P4) of all parts groups and the total relative labor intensity of each group. If the line-group lines (sections) and the GAL are usually formed for the manufacture of parts of one typogram, taking into account the proximity measure between the basic and attached groups of parts, the route sections can be formed not only from one but also from different types of groups, so that on the basis of P 3 the sequence of basic technological operations is not violated. Here, too, there is no need to take into account, among the characteristics, the average value of the index of relative labor intensity by detail group K gm (feature P 5). The total relative labor intensity of each group of parts is used to form equal-sized route sections. The measures of the distance R i and the proximity are calculated only for the first three criteria Pi, Pi, > P 3.

Area of ​​application of route sections

The flow-group sections are usually used in such production conditions, when up to 50 items are passed through each workplace per year ( K m 0.02), and every month the workplace is fixed to 20 operations, which corresponds to the conditions of stable medium-term production.

Podetalno-specialized areas with a flexible form of production organization (flexible sections) can have machine modules (CM) or GAL, through which within a year they pass up to 500 items (this corresponds to K mi & gt; 0.002), i.e. in such production conditions, more than 40 operations are carried out at each workplace or machine module per month, which corresponds to the conditions of a single production. The technical base of flexible sections is the CNC and CM.

If we take into account that the annual growth rates of the CNC and SM production are approximately 4% and that each CNC and SM is practically replacing 2-5 conventional metal-cutting machines, the full saturation of the machine building complex with modern metal-cutting equipment will take place only in 20 years (to the base of 2000 g.). Today, the use of CNC and CM in machine-building enterprises is limited, with the help of which slightly more than 10% of the volume of work on machining is performed.

Therefore, the route sections are especially attractive - they can be organized in the conditions of any inaccurate production, and their effectiveness is greater, the more operations are assigned to one workplace. Since the route sections are sub-specialized, they are approaching 0.7-0.8 efficiency levels of the flow-group sections in efficiency, and the one-time costs for arranging a group-by-section area are almost 10 times greater.

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