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Education Education | Teaching Labor-aided design of technological processes, machining
Education Education | Teaching Labor-aided design of technological processes, machining
| Labor-aided design of technological processes, machining |
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| Written by Войтенко В.И. Стрильчук А.М | |
| Thursday, 15 January 2009 | |
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The text of the original in Russian The analysis of labor «traditional» (without EOM) design machining processes. Investigation of the burden of individual stages of the automated design of routing and operational descriptions of TA machining in a CAD TA mixed. Labor-aided design of technological processes, machining Design of machining processes without the use of EOM is very laborious. Thus, in the heavy machine-averaged structure of real time to develop a process route with a choice of equipment for operations represent-tion 4-25 h; development operations to the level of the transition with the appointment of equipment, calculations of modes of cutting and rationing - 10-80 h; development operating and design sketches -2-40 h; design fixtures - 2-150 h; design a special tool - 0,5-50 h. In some cases labor CCI is much higher than labor-tank design of the production technology (CPT). Complexity of the CPR in a number of examples of the unit, batch and mass production exceeds the pro-labor CCI 2-5 times. In any design there are four groups of tasks: documentation, information retrieval, the model calculations and structural solutions. Fig. 1 shows the ratio of problems solved in the traditional design of TA machining. In the first three groups of tasks should be attributed to the «routine»  Fig.1. Structure design of TA and their total share is about 90%, leaving the most complex intellectual tualno «creative» tasks no more than 10%. So design documentation is 30-50% of the total cost of design, search information is 15-20%, 30-40% of the model calculations, structural solutions, lo-logical analysis and decision-making - up to 10%. Application of CAD TA machining processes significantly reduces the labor of designing. The study design with the use of the labor system Sapr_2003_08 (development Voitenko VI) mixed type, was carried out among a group of students of Bachelors of Mechanics and Machine Building Institute National Technical University of Ukraine «Kiev Polytechnic Institute». Applied detail drawings of medium complexity with the number of surfaces 15-20. In general, the design methodology is similar to the first two levels of project tirovaniya set forth in the works Tsvetkov VD called «Multi-level iterative method of design». A: 1. decomposition details to the basic surface, but the synthesis of structural and technological details of the model in accordance with the ranks surface; 2. Automated synthesis of plans of each surface treatment (retained in the working version of the MC) with the use of algorithmic modules Sapr_2003_08; 3. development of a concept TA; formation in each of the larger stages of technological operations and their Ranjit-ing; synthesis formulas of TA; 4. editing status of operations and changes in the working version of the MC in accordance with the structure; 5. Issue final document «Form 3 CAD GOST 3.118-82» diagrams and labor operations, and labor by type of equipment. Number of people who took part in the study - 15. The research results presented in the form of diagrams showing trudoem-bone, the ratio of labor during the design and the total time of work. The formation of the MC today remains the least automated bathroom design phase of the MC. The formation of the MC is done online, which increases the design. Reducing the burden of design may be the development of models and algorithms that provide improved automatic object design procedures:  1. Sketch, and decomposition details 2. Structural and technological model 3. Schematic diagram of the MC 4. Composition of manufacturing operations. 5. Formula structure TS This chart shows the allocation of time on stage. Most of the time spent on design details and design elements of the allocation of packing surfaces (30%), which is characteristic of the educational process with you-tion test and an exam. Accordingly, at least, the synthesis formula of TA (11%).  As we see from figure 1, the most time on stage 1 was 27 min. (Article number 7). Not hard to guess that figure would have such a kind as each student requires different amounts of time for execution, even the same tasks. In this case, everyone - different tasks (the original drawings of parts).  At different stages are obtained considerably different maximum values at the time of their execution, as differing amounts of the necessary work.  The development concept is an integral part of TA, which is the second largest amount of time for execution.  Writing formulas in the existing structure of the TA process operations, perhaps the easiest, but this does nemalovazhen, plot work.   A summary diagram of the overall time. The final document contains a route description of the MC-operation with the technical norm. Operation to secure the appointment of equipment. Technological transitions contain requirements for the accuracy provided by the size and requirements for surface roughness, a full description of the cutting tool showing the code, name, size, material and cutting of the standard for manufacturing, cutting regimes, the standard of normal time and cost of energy. Overall the design of maximum 100 min. That significantly less than the «10-80 h», described earlier. |