在图1中,在力 F_τ作用下,螺纹连接强度取决于承受剪应力的螺栓截面强度。应预先说明:螺纹连接件承受的拉紧力值往往取决于连接件的强度和连接的紧密程度。但是,随着力 F_τ的增长,一方面在螺栓的危险截面上出现和力 F_τ成比例增长的拉应力和扭转应力τ_(kp),这些应力都要减弱螺栓的 In Figure 1, under the action of force F_τ, the strength of the screw connection depends on the strength of the bolt section subjected to shear stress. It should be stated in advance that the value of the tightening force to which the threaded connection is subjected always depends on the strength of the connection piece and on the tightness of the connection. However, with the increase of the force F_τ, on the one hand the tensile and torsional stresses τ_ (kp) increase in proportion to the force F_τ on the dangerous cross-section of the bolt,