People who have studied mechanical principles generally know that. By spiraling, the helical movement of the nut becomes a linear movement along the axis of the bolt. Fastening and dismantling of the coupling are achieved by tightening and loosening the screw.
If we present their spirals, the fit between them is actually equivalent to the mating of the object with the bevel. The reason why objects do not fall on slopes is mainly related to their materials (that is, friction) and the angle of the slope. There is a friction angle between the object and the inclined surface. As long as the angle of the inclined surface is smaller than the friction angle between the object and the inclined surface, the object will not slide down from the inclined surface. This is the principle that after the nut is tightened it will not automatically loosen. The spiral is similar to that of the bevel so it is very labor-saving. A small force in the spiral direction can get a large force in the axial direction of the bolt, that is, the very tight connection of the workpiece.
And why do the screw caps have a regular hexagon? Because honeycomb is a structure that combines growth and expansion perfectly. Cellular expansion is the most sophisticated and can withstand tremendous external pressure and be shared and accepted to offset. The bees are centered on the queen bee, clockwise around the building of countless tightly-coupled beehives. When the worker bees build their nests, they will complete each room side by side, and the walls of each room are shared with the neighboring rooms, so the most economical material will not be too heavy, and its shape will naturally form under the influence of gravity. The hexagonal shape achieves the most sturdy construction and materials in the province.