Despite being one of the most fundamental parts of engineering and construction, bolt manufacture has developed into a sophisticated, high-tech process requiring several processes. Learn how metal tools with exact specifications are made from raw steel. Bolts can be produced in a wide range of diameters and shapes, but the basic manufacturing process often remains the same. Steel wire is first cold forged into the desired shape, then heat treated to increase strength and surface treated to increase durability, and then packaged for transportation. For more sophisticated bolt designs, the production process may need a few extra processes.
Cold forging
Large steel wire rods are uncoiled and trimmed to length before cold forging begins. In essence, the steel is shaped in this location while still being at room temperature by being pushed through a sequence of dies under intense pressure. Bolts can be made fast, in Hᴜɢᴇ quantities, and with high consistency thanks to cold forging once it has been mastered. For more complex bolt designs that cannot be curved through cold forging alone, additional turning or drilling may be necessary. During turning, steel is removed as the bolt is rapidly spun to create the required form and pattern. To create holes through the bolt, utilize drilling. If necessary, washers may also be placed on some bolts at this stage of the process.
Heat treatment
All bolts must undergo the normal heat treatment procedure, which entails subjecting the bolt to extremely high temperatures in order to harden the steel. When the steel is softer, threading is frequently carried out by rolling or cutting before heat treatment. Rolling involves putting the bolt through a die to create threads in the steel, much too cold forging. It is simpler and more affordable to apply the heat treatment to the thread beforehand because it will alter the characteristics of the steel and make it harder. Better fatigue performance will result from threading after heat treatment.
Size and surface
Long bolts longer than ten times the diameter of the bolt may experience the steel returning to its original round shape as a result of the heat treatment. Therefore, it is frequently necessary to apply a straightening technique. The application of the bolt and the customer’s specifications influence the choice of surface treatment. Fastener corrosion resistance is frequently the main issue, so a zinc-plated coating applied via electrolytic treatment is a typical remedy.
This procedure involves immersing the bolt in a zine-containing liquid while applying an electric current to cause the zinc to coat the bolt. However, electrolytic treatment does result in a higher level of hydrogen embrittlement in the product. Zine flakes are a further choice; they provide even greater corrosion resistance but come at a higher cost. The bolt is finished once these procedures are finished. The bolts can now only go through some sort of quality control to assure consistency and uniformity before being packaged and transported.
Thank you for visiting our website! We hope you found soᴍᴇᴛʜing that sparked interest on our website.
Video resource: StarTech TV