button head

基本解释

Includes Low Head, Button Head, and Flat Head Screws, as well as special Socket Cap Screws such as Vented, Drilled Head, Self-Locking, and more.
包括低压头，半圆头及平头螺丝以及特殊内六角圆柱头螺钉如排空，钻孔头，自锁，等等。
The joint of external thread shall be weld the container or pipes, cover the nut with spherical joints, and the button head shall be weld on relevant pipes;
外螺纹的接头焊在容器或管路上，将螺母套入球面接头后，球头接头与相应的管路焊接；
Make the pipes with button head align with the joints of external thread, rotate the nut and make it align to the center, knock the nut and screw up the nut.
将焊有球头的管子与外螺纹接头中心相对，旋转螺母使其自动对中心后，敲击螺母使螺母旋紧。

If apes see a man pressing a button with his head because his hands are occupied holding a blanket, they will press the button with their hands.
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