Hexagon socket screws are often used in machinery, mainly for fastening, disassembly, not easy to slip Angle and other advantages. The inner hexagon wrench is generally a 90° bend, the bend end is long and the other side is short. When using the short side to beat the screw, holding the long side can save a lot of force and better fastening the screw. The long end has a round head (hexagonal cylinder similar to a sphere) and a flat head. The round head can be conveniently disassembled diagonally, and some parts of the wrench are not convenient to install. The manufacturing cost of the outer hexagonal is much lower than the inner hexagonal, and its advantage is that the screw head (wrench force position) is thinner than the inner hexagonal, and some places are not the inner hexagonal can be replaced. In addition, the cost is low, the dynamic strength is small, the precision requirements of the machine using hexagon screw is much less than the outer hexagon.

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