Stainless steel to prevent locking

  The length of the bolt should be chosen appropriately, 1-2 tooth distances shall prevail after tightening the exposed nut. The tensile strength of bolts and the safety of nuts meet the design requirements.  Clean the thread before use. If the thread is damaged, at least the nut can pass smoothly.  Tighten the nut.  The force direction of wrench must be perpendicular to the axis of bolt, do not tilt.  Use torque wrench, avoid using electric wrench, torque value within the safe torque range, uniform force applied during rotation.