Automatic CNC code generation in process planning of rotational and prismatic parts

Tornalama ve Frezeleme imalatta en çok kullanılan iki talaş kaldırma işlemidir. BSD (Bilgisayar Sayısal Denetimli) takım tezgahları, BDT/BDÜ (Bilgisayar Destekli Tasarım ve Üretim) endüstrisinde imalat faaliyetlerinin köşe taşı konumuna gelmiştir. Bu makinalar üzerindeki işlemler parça programı adı verilen bir emir seti ile gerçekleştirilmektedir. BDT/BDÜ içerisinde, dönel ve prizmatik parçalar için hatasız parça programlarının tamamen otomatik olarak türetilmesi büyük önem kazanmaktadır. Bu makalede, CNC torna ve freze tezgahları üzerinde dönel ve prizmatik iş parçalarını işleyecek parça programlarının otomatik türetimi ve kontrolü için geliştirilen iki sistemin geliştirilmesi ve kullanılması açıklanmaktadır. Otomatik parça programı türetimi ISO (G ve M kodları) kullanılarak yapılmaktadır. Makalede sunulan her iki sistem de bir kişisel bilgisayar üzerinde ve C programlama dili kullanılarak geliştirilmiştir. Bu sistemler yalnız başlarına ayrık sistemler olarak kullanılabildiği gibi, OPPS-ROT ve OPPS-PRI isimli iki işlem planlama sistemine entegre modüller olarak ta kullanılabilmektedir. Geliştirilen sistemler oldukça kompleks iş parçaları için denenmiş ve sanayide kullanılmıştır. Geliştirilen sistemlerin uygulamalarının anlaşılabilmesi için makalede pratik örnekler verilmiştir.

Prizmatik ve dönel parçaların işlem planlamasında otomatik parça programı türetimi

Turning and muling are two of the most common metal removal processes in manufacturing. CNC machine tools have become corner stones of the manufacturing facilities in CAD/CAM industry. They are driven by a set of instructions called part program. Fully automatic generation of error-free CNC part programs for machining rotational and prismatic parts has therefore a great importance for the CAD/CAM industry. This paper reports the development and implementation of the two systems providing the generation and verification of part programs required to manufacture the rotational and prismatic parts including complex cavities on CNC turning machines and CNC milling machines, respectively. The automatic CNC code generation is based on standard ISO (G&M) codes. Both systems were implemented in C programming language and on a PC. They can be used as stand-alone systems or as integrated modules of the process planning packages called OPPS-ROT (Optimised Process Planning System for ROTational parts) and OPPS-PRI (Optimised Process Planning System for PRIsmatic parts), respectively. The developed packages have been tested for relatively complex parts and applied in machining industry. Practical examples are given in the paper to illustrate the applications of the developed systems.

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