The core bit includes shank and thread, which consists of male thread and female thread.

有直柄钻头和螺纹柄钻头之分，螺纹柄分为内螺纹和外螺纹。

youdao

Adopting the new method to female thread machining, high hardness of thread can be acquired, and tap broken cases reduce significantly.

采用振动挤压攻丝新方法对钛合金材料进行内螺纹加工，螺纹表面硬度高，丝锥损坏现象显著减小。

youdao

With features of superhigh hardness and strength, the cutting tool is broken down frequently when female thread was processed using titanium alloy.

钛合金材料由于存在硬度高、强度大等特点，在进行内螺纹加工过程中刀具经常损坏。

youdao

Alternatively for more unusual, unbranded souvenirs, visit the Women's Handicraft Centre (Karama St, Al Mushrif), where local female artisans produce weaving and thread-work, or don your haggling hat at the carpet souq on Al Meena Road.

BBC: Stopover in Abu Dhabi