The bionics theory was applied on the spiral bits, and then a non-smooth spiral bit was designed and processed for carried out the problem of serious sticking.

将仿生非光滑理论应用于螺旋钻头设计上，以解决粘性土钻进中螺旋钻头阻力大、粘附严重的难题。

youdao

In the photo, the spiral striae left by the drill bit can clearly be seen in the plug of the lock.

在图片中，可以清楚地看到锁芯里的由钻头留下的螺旋状印迹。

youdao

The model includes of important characteristics of drill bit and drilling operation, i. e. sectional geometrical property of drill, spiral Angle, speed and cutting force created during drilling.

该模型包括了钻头以及钻削操作的重要特性，即钻头的截面几何特征、螺旋角、转速和钻削过程中产生的切削力。

youdao

The game continued in a bit of a downhill spiral for another minute or so.

FORBES: Top Leaders Share The Best Advice They Ever Received

" He adds a bit later: "That we live in a large spiral galaxy with very little central stellar bulge and a modest central black hole may be a clue to the type of galaxies best suited to life: ones that did not spend their pasts building colossal black holes and fighting the demons unleashed in the process.

WSJ: Book Review: Gravity's Engines