The design of bit crown is an important part of polycrystalline diamond compact (PDC) bit design, although predecessors have done a lot of researches on the design principles of PDC bit crown, the study of the law about rock-breaking energy consumption according to different bit crown shape is not very systematic, and the mathematical model of design is over-simplified. In order to analyze the relation between rock-breaking energy consumption and bit crown shape quantificationally, the paper puts forward an idea to take “per revolution-specific rock-breaking work” as objective function, and analyzes the relationship between rock properties, inner cone angle, outer cone arc radius, and per revolution-specific rock-breaking work by means of explicit dynamic finite element method. Results show that the change law between per revolution-specific rock-breaking work and the radius of gyration is similar for rocks with different properties, it is beneficial to decrease rock-breaking energy consumption by decreasing inner cone angle or outer cone arc radius. Of course, we should also consider hydraulic structure and processing technology in the optimization design of PDC bit crown.

中文翻译：

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PDC钻头冠形优化设计的数值模拟研究。

钻头冠的设计是多晶金刚石复合片（PDC）钻头设计的重要组成部分，尽管前人对PDC钻头冠的设计原理进行了很多研究，但根据不同的设计方法对碎石能耗规律进行了研究。钻头冠的形状不是很系统，设计的数学模型过于简化。为了定量分析碎石能耗与钻头冠形之间的关系，提出了以“每转碎石功”为目标函数的思想，并分析了岩石性质，内锥度之间的关系。角度，外锥弧半径和每转特定的破岩功，采用显式动态有限元方法。结果表明，对于性质不同的岩石，每转岩石破碎功与回转半径之间的变化规律相似，有利于减小内锥角或外锥弧半径来降低破碎能耗。当然，在PDC钻头冠的优化设计中也应考虑水力结构和加工技术。