Thru-bolts can be defined as bolts that pass completely through a layer and bind by way of a nut on the layer’s other side. Thru-bolts are the strongest and most reliable of all types of bolts, making them the bolt of choice for the most heavy-duty of applications. They are able to withstand a large amount of weight and alleviate any safety concerns an application may have.
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Applications of Thru-Bolts
Applications in which thru-bolts are utilized span a multitude of industries, including in rolling shutters, security grills, sun awnings, and garage doors. Since thru-bolts are durable and strong, they are recommended for use whenever possible. For example, when building a deck, it is recommended to use thru-bolts on railing posts and deck ledgers, and more specifically, at connections where ledgers attach to posts or the building itself.
Thru-Bolt Design and Manufacturing Process
In general, bolts can be made from a wide range of metals, such as stainless steel, aluminum, brass, copper, bronze, nickel alloys, and titanium. Materials like cast iron, silicon, tungsten, cobalt and its alloys, rhodium, and rhenium are too brittle to be used. The manufacturing process for a bolt is similar to that of other fasteners. The first step of the process involves heating a metal rod, cleaning it with sulfuric acid, and applying a coating to prevent rusting. The next step involves a method known as cold forming, also known as cold heading. In the cold forming method, the metal rod is formed and shaped at room temperature and at high pressure. The final touches are applied by forcing the metal rod through at least one die and then cut to the desired length.
The cold forming method is highly advantageous to other methods, such as machining, when it comes to manufacturing thru-bolts. Cold forming is a highly flexible method. Parts can be hit multiple times and can either be moved through one die or transferred through a series of dies that progressively shape the rod into a complex configuration. Because of the variety of ways that the cold forming process can be modified, the range of shapes that can be formed is remarkably broad. Bolts that are cold formed can feature different shaped heads, threads, grooves, knurls, and tapers, depending on the application and the desire of the manufacturer. In the long run, cold forming reduces scrap and allows manufacturers to save more material. It also helps to save material due to the high speed of the process. As opposed to screw machining, which involves the interruption of grain flow, the cold forming process rearranges the grain structure of the bolt, thus increasing the shear strength performance of the final product. You will wind up with bolts that are consistent, of high quality, and with a smooth surface finish. In turn, there is no need for the bolts to undergo any type of secondary finishing. Finally, the cold forming process allows the manufacturer to convert multi-part units into a singular component if they so choose, which can potentially help a company save on inspection, labor, tolerance issues, purchases, inventory coordination, and assembly time.
Factors to Consider When Purchasing Thru-Bolts
Thru-bolts are greater in size and thickness compared to other types of bolts because of the amount of weight they are expected to handle. Many applications require the lifting of heavy loads and need the proper amount of support. Since there may be safety risks that come with choosing the incorrect thru-bolt for your intended application, the thickness and length of the bolt are important factors to consider. The thicker the bolt, the more weight the bolt will be able to withstand and the less likely the bolt will break or snap. The length of the bolt must also be long enough to pass through a layer or material and be secured on the other side by a nut.
Finding a reliable, experienced thru-bolt manufacturer will ensure that you receive a thru-bolt that best fits your application. Before meeting with the manufacturer, it is important that you know the specifications of your application thoroughly. A seasoned manufacturer will be able to assist you in finding the best possible thru-bolt if they know as much detail about your situation as possible. Knowing you have a thru-bolt that perfectly suits your needs and will provide reliable support will bring you peace of mind in the applications for which the bolts will be used.