Special fasteners, including bolts, nuts, washers, and other components, are designed to meet specific requirements beyond the standard fastening needs. These specialized fasteners are often engineered to provide enhanced performance, durability, or unique features to suit particular applications.
High-Strength Bolts : These bolts are manufactured from materials that offer higher tensile strength and may be heat-treated for added toughness. They are commonly used in applications where structural integrity and load-bearing capacity are crucial.
Stainless Steel Fasteners : Stainless steel bolts, nuts, and washers are resistant to corrosion and rust, making them ideal for applications in environments with high moisture or chemical exposure.
Non-Corrosive or Corrosion-Resistant Fasteners : For applications in corrosive environments, special fasteners made from materials like titanium or corrosion-resistant alloys may be used to prevent rust or degradation over time.
Special Coatings : Fasteners can be coated with materials like zinc, chrome, or other anti-corrosive coatings to enhance their resistance to environmental conditions.
Custom Threads and Sizes : Some applications require fasteners with non-standard thread sizes, pitches, or lengths. Customized fasteners can be manufactured to meet these specific requirements.
Security Fasteners : These fasteners are designed to resist tampering and unauthorized removal. Examples include security bolts with unique drive shapes that require special tools for installation and removal.
High-Temperature Fasteners : For applications where extreme temperatures are a factor, special fasteners made from heat-resistant alloys or ceramics may be used to maintain structural integrity under heat stress.
Aerospace Fasteners : Aerospace applications often demand fasteners with stringent specifications for strength, weight, and corrosion resistance. These fasteners are designed to meet aerospace industry standards.
Specialized Washers : Washers may be designed with specific features, such as spring washers for providing tension or Belleville washers for high-stress applications.
When considering special fasteners, it's important to adhere to industry standards and specifications. The choice of materials, coatings, and designs should align with the specific requirements of the application to ensure optimal performance and reliability. Consulting with fastener experts or manufacturers can help in selecting the right special fasteners for a given application.
Carriage Bolts provide simple installation and versatility when assembling a variety of building materials, not only with hardened steel, but also for softer materials like wood & plastic. They are designed with a smooth, large diameter head that resists pull-through in softer materials and a square neck that prevents the bolt from turning when tightening the nut.
Flange bolts have a round flange beneath the head that distributes the load like a washer. Because of this feature, it’s the preferred choice for metal to metal fastening.
Plow bolts commonly have a square neck, to stop the bolt from rotating as it is being tightened, and a flat head, where the head of the fastener is subjected to excessive amounts of wear. These fasteners are frequently used in farm machinery, heavy machinery for building roads, and other equipment.
Hex bolts, sometimes called hex capscrews or machine bolts, are structural fasteners that have hexagonal heads and machine threads. They’re meant to be used with a nut and washer as part of a total fastener assembly. They may also be installed directly into a tapped hole.
Square head bolts are utilized in applications where strong fastening is needed but visibility is restricted. These bolts are simple to tighten with a wrench and have large, flat sides. Square heads work best in small, dim areas where a fabricator or machinist must blindly tighten the bolt. Even without any visible marks, it is easy to fit a tool across the square head, reducing the likelihood of tool slippage.
Threaded fasteners with a recessed hexagon drive and a cylindrical head are known as socket head cap screws. Socket screws, also referred to as Allen head screws, are tightened to far greater torque standards than a crossed recessed or slotted drive fastener. They are twisted using a hexagon-shaped key, also known as Allen wrenches, hex-key wrenches, or hex keys. In circumstances where there is not enough clearance to utilize a fastener with an exterior hexagon head, socket head cap screws are frequently used.
The J bolt, which is frequently viewed as half of a U bolt, has a long threaded part and a smooth curve that can both be used to fasten objects in place. Because of its adaptability, the J bolt can be utilized in a variety of situations, such as the automobile, locomotive, and building and construction sectors. It is also used in household settings for do-it-yourself projects like hanging baskets and deck building.
A “U”-shaped curved bolt having threaded holes on both ends is known as a “U bolt.” In addition to being employed in a variety of building and construction applications, these fasteners are used to support piping. These fasteners are used in piping support, as well as in various building and construction applications.
Mainly used in an assembly to lift or suspend a load (usually a machine), eye bolts are characterized by a loop in one end & a threaded rod on the other.
For wood connectors, button head or round head bolts are frequently used. round head bolts resemble carriage bolts but lack the square neck that surrounds the head. Round head bolts are rarely high strength and almost always offered in a basic ASTM A307 specification because they are frequently used with wood.
T-Head bolts are typically used with nuts to link an object with a T-shaped groove such that the bolt head fits flush or below the material surrounding it.
Coupling nuts, commonly referred to as extension nuts, are threaded fasteners used to connect two threaded rods. The hexagonal exterior of these nuts enables safe tightening and loosening with an installation tool.
A hex flange nut is basically a nut with a built-in flange underneath it. The smooth bearing surface of the flange acts like a built-in washer, distributing the clamp load wider away from the nut, replacing a traditional nut and washer assembly.
Hex nuts have six sides. When no “locking” mechanism is needed, these nuts with internal threading are frequently used with machine-threaded bolts and screws.
Lock nuts have a built-in mechanism inside the nuts to prevent itself from loosening from vibrations. There are different variations of lock nuts:
Slotted nuts have grooved heads that fit into holes in the bolt when they are joined, allowing for the cotter pin to be inserted and holding the nut in place. They are utilized in situations when the locknut might become loose due to vibration or motion.
In contrast to slotted hex nuts, castle hex nuts have cylindrical slots that are roughly equal in length to the depth of the slot and somewhat smaller in diameter.
A square nut is a four-sided nut that is often used with square-headed bolts. Square nuts, as opposed to traditional hex nuts, provide a larger surface area in contact with the part being fastened and hence offer more resistance to loosening.
A wheel nut, also known as a lug nut, is a fastener that is used to hold a wheel to a vehicle. Typically, these nuts are found on cars, trucks, and other sizable rubber-tired vehicles. The majority of aluminum and steel wheels employ wheel nuts, which have with one rounded or conical (tapered) end. A set of wheel nuts is typically used to fasten a wheel to threaded wheel studs and subsequently to the axles of a vehicle.
A nut with a domed end on one side is referred to as a cap nut. When paired with a threaded fastener that has an exterior male thread, the domed end encloses the external thread to either protect it or keep it away from neighboring items. The dome also creates a more polished appearance. There are different types of cap nuts, such as acorn nuts (where the domed side is pointed and has a taller crown)
A wing nut , also known as a butterfly nut, is a type of nut having two sizable metal “wings,” one on each side, making it simple to tighten and loosen by hand without the use of any tools.
Beveled washers are a unique kind of washer that have a flat side and a slanted side. Different installation angles can be accommodated by the sloped side, which also enables a stable and tight fit when mating and aligning two non-parallel faces.
When a screw or bolt is tightened, flat washers uniformly distribute pressure. Its thin, plate-like design increases surface area to stop a fastener from loosing and pulling out. Additionally, they reduce surface friction and serve as spacers when extra distance between items is required.
Lock washers are made to be tightened to the necessary torque just below a regular fastener. The fastener is prevented from vibrating loose by the spring tension they apply. They are frequently fastened to the fastener’s nut side.
When used with high-strength fasteners, structural washers are thick, heavy-duty, and designed for mechanical and structural applications. They are frequently found in steel-to-steel couplings for bridges, structures, and other infrastructure.
Industrial fasteners like bolts and nuts are commonly used in different industries, such as: