With the development of the aerospace industry, the demand for aerospace fasteners has increased rapidly. As aerospace fasteners are applied under an environment of high temperature, high pressure, and high intensity, their quality requirements are also particularly high. Here, we introduce some useful knowledge about aerospace fasteners.
What are aerospace fasteners?
The fastener is one kind of mechanical part that connect two or more parts that connect two or more parts together. The application is extremely wide. Aerospace fastener refers to the fastener which is specially used for the aerospace industry. It adopts specific materials with special properties or applications.
Aerospace fasteners are generally used in airplanes, satellites, and rockets. It is a typical high-end fastener. It is also a kind of important necessary basic part of aerospace aircraft. The performance requirements are much higher than the fasteners in other fields. There’re various kinds of aerospace fasteners and each category contains different specifications and types to meet the diverse needs of different materials and structures.
What are the categories of aerospace fasteners?
1. According to whether the fastener can be removable, it can be classified into removable fasteners and permanent fasteners. The removable fasteners include bolts, screws, and nuts. Permanent fasteners include high-locking nuts, rivets, etc.
2. According to product types, can be classified into bolts, screws, nuts, single-sided fasteners, special fasteners, etc.
3. According to the materials used in fasteners, it can be divided into carbon structure steel fasteners, alloy steel fasteners, stainless steel fasteners, high-temperature alloy fasteners, aluminum alloy fasteners, titanium alloy fasteners, non-metal fasteners, etc.
4. According to the differences in the requirements of the assembly operation, it can be divided into single-sided fasteners and double-sided fasteners.
Commonly used important aerospace fastener
Rivet fasteners
The rivet fastener which is applied in aerospace, quality guarantee and lightness are the most important choice factors. It is one of the most widely used fasteners on aircraft. The materials are aluminum alloy, stainless steel, heat-resistant alloy, titanium alloy, etc. Most rivets adopt composite materials, such as aluminum alloy, and titanium alloy. With the continuous improvement of the rivet material intensity, the support rivets used in corresponding important parts have also been developed, such as dual metal rivets and high shear rivets and their strength can reach the intensity of titanium alloy high lock bolts.
Bolt fasteners
The mostly applied fastener used to bear the larger parts of the aircraft is the bolt fastener which mainly includes ordinary bolts, high lock bolts, and tapered bolts. A high lock bolt is a single-sided thread fastener which is a type of bolt that is widely used in the aerospace industry. For airplane design, weight loss is an important indicator. The use of high-ratio intensity materials can achieve the replacement of large-sized fasteners with lower intensity. In addition, the anti-fatigue, corrosion resistance, rigidity, brittleness, compatibility, heat resistance, and other properties, also are needed to be considered.
Nut fasteners
Nut fasteners are used together with bolts. They have a variety of structural forms to meet the applications of different occasions, including hex nuts, bihexagon nuts, bracket nuts, barrel nuts, and high lock nuts, most of which adopt a self-lock structure. The hexagonal nut has been applied to the airplane in a large amount. The bihexagon nuts are widely used on the engine and high-strength bolts.
Single-sided fastener
There are two main forms of fastening parts used in the open parts of the airplane. One is the bracket nut/bolt and fast unloading fastener used in the removable parts such as the aircraft hatch. The other one is a single-sided nail used in the permanent connection part. The screw thread nail is specially designed for the composite material structure, which can improve the performance of sealing and anti-fatigue.