It seems reasonable to think that the tension on a scre […]
It seems reasonable to think that the tension on a screw / bolt is the sum of the initial clamping load plus any external loads, but this is not so. Consider the following picture and imagine that the screw (or spring) is clamping the red box against the ground with 10 lbs of force. Now, if you were to pull up on the red box with 5 lbs of force, would the tension in the screw increase to 15 lbs? No, your 5 lbs of upwards force would only reduce the pressure between the red box and the ground; it would not stretch the screw at all. In fact, the screw would not feel any change in force whatsoever until the upward force exceeded 10 lbs and the reb box lifts. The force / tension in a spring depends only on its stretch (F=kx), and if the bolt head isn't moving, the tension isn't changing.
Generally has square or hex-shaped head and is available in many variations of thickness and finish
There are many different threads that can be used when building a rod. They vary from color treated (thread that has already been treated with color preserver), regular nylon, metallic, and even polyester.
Keep in mind Metallic thread is not as strong as regular nylon thread so it’s best to only use metallic thread for doing decorative butt wraps, trim bands, or inlays.
We also produce tie Thread Rod, non-standard shaped pieces can be custom made according to samples or drawings. And Other parts fastener , like nuts, washer ,Our products are exported to Europe, America, Australia, Asia and Africa, favored by consumers.