Tricone Bit Cad System

Tri-cone rock bits are important tools in oil drilling .Products have been formed into many series. As the exploitation of oil penetrated continuously, the consumers required them to have better manufacture technologies and higher design .In order to consumers' requirements, the manufacturers of cone rock bits must ameliorate the structures of cone rock bits, improve the performance of cone rock bits, shorten the period of design and manufacture, reduce cost, improve the competition of market.So it is very important to improve and enhance the design means with advanced CAD technology.We chose AutoCAD as the secondary development environment, and adopted viewable interface and ActiveX Automation technology .We made use of its secondary development language VBA to develop tri-cone rock bit computer aided design system software. The thesis's primary research work was as follows:1. The thesis has executed system's holistic frame design, established system's database, confirmed tri-cone rock bit's function module and system's organizing structure, It made system divide into interface supervising module, bit geometry structure design module, database supervising module, parametric drawing module, assistant function module and so on;2. The paper analyzed many key questions of system realization, for example, AutoCAD as the secondary development technology, database technology, parametric drawing technology, interface and popupmenu technology etc. At the same time, I put forward and realized the resolvent of many key questions of system realization;3. The software used the language of VBA to realize program, It made cone parts' design and assistant drawings to integrate uniform environment trough modularization mode and parametric drawing method. So it really realized design and drawing to turn into uniform;4. The system has realized the tri-cone rock bit's parametric protraction of the engaging drawing, the drawing of breaking rock on the hole and the drawings of three cones by developing AutoCAD using the VBA as the tool;5. The thesis has executed system's assistant function design, It realized frame and title bar's drawing, table drawing, surface roughness tolerance's label, norm symbol's label and shape tolerance's label and so on to complete rapidly.The study in this paper had practical meaning in increasing the design level and the design efficiency of tri-cone rock bit , in applying CAD/CAM technology, and inimproving the ability of prompt reflection to the market and competition of enterprises.