Tubular rivets, or solid rivets, are the oldest and most reliable fasteners in woodworking and other industrial works. Rivets are permanent mechanical fasteners and consist of a smooth cylindrical shaft. For the installation of a rivet, the rivet is placed in a pre-drilled or punched hole, and the tail is bucked or upset so that the tail expands to 1.5 to 2 times its diameter. The head of a rivet is known as the factory head, and the tail is known as the shop head. The head of rivets allows them to support high tension loads, albeit they are better suited for supporting shear loads. Typically, there are basically two types of rivets: tubular or solid rivets and semi tubular rivets. However, it should be noted that there are other kinds of rivets commercially available. The abovementioned are the two main types, both of which are sturdy and economical for use in production.
As mentioned earlier, tubular rivets are the more traditional type of rivets. They consist of a cylindrical shaft and a head. The tail of this rivet is deformed using a hammer, a rivet gun, or a crimping tool; it can also be expanded using a rivet compression tool. Tubular rivets are usually used in applications where there is a need of extra safety and reliability. For instance, solid or tubular rivets can be found in the structural parts of an aircraft. Such rivets are made up of aluminum alloys or titanium and nickel based alloys.
Semi Tubular Rivets
As the name suggests, semi tubular rivets are similar to tubular rivets, albeit they have a partial hole at their tip. This hole allows the worker to reduce the effort required to fasten the rivets. To fix the rivet, the tubular portion has to be simply rolled outwards. Due to the hole at the tail, semi tubular rivets can also be used as pivot points. Since the semi tubular rivets expand radially, they do not interfere with movement. These rivets can be installed using pneumatic tweezers, kick presses, handsets, manual squeezers, PLC-controlled robotics and impact riveters.
Semi tubular rivets are used mostly in brakes, binders, lighting, ladders and other mechanical and electronic products. They are available in a variety of diameters and sizes and have varying lengths. They are also available in a wide variety of materials and platings. The most common production materials and platings include zinc, stainless aluminum, nickel, tin and brass. A semi tubular rivet, when applied and finished, has a head on one side and a shallow blind hole exposed on the other.
Tubular Rivets vs. Semi Tubular Rivets
Semi tubular rivets are superior to tubular, or solid, rivets in that the latter can only be used when access to both sides of the structure is permissible. Therefore, tubular rivets cannot be used on closed structures. They are mostly found on static structures like cranes, bridges, wooden boats and building frames. Further, tubular rivets require a lot of force for installation, and again, are inferior to tubular rivets that require only ¼ of the force required to fasten a tubular rivet. Moreover, tubular rivets are quite reliable, particularly in situations where safety is paramount.