1.20 : Steel Fastening Techniques

Steel sections can be joined together through various fastening techniques including riveting, bolting, and welding, each suitable for different structural requirements and conditions.

Rivets are cylindrical steel fasteners with a specially designed head. During application, rivets are heated until white-hot and then inserted through pre-drilled holes in the steel sections. A pneumatic hammer is used to shape the exposed end into a second head, securing the sections together.

Bolting is another common fastening method where bolts are inserted into holes that are slightly larger than the bolt diameter, typically by one-sixteenth inch. Hardened steel washers are often placed under the bolt heads or nuts to distribute the load and prevent damage to the steel. Bolts are tightened using pneumatic or electric impact wrenches to ensure a secure fit.

Welding creates a strong, seamless bond by melting the steel pieces at the point of contact. An electric arc is generated between a metal electrode and the steel sections. This arc melts the electrode's tip and the adjoining steel surfaces, forming a molten puddle. The electrode is progressively moved along the seam, depositing molten metal that solidifies to form a continuous, durable joint.

These techniques provide robust solutions for assembling steel structures, each offering different benefits in terms of strength, efficiency, and application suitability.